- Efficient electrocatalytic hydrogen gas evolution by a cobalt-porphyrin-based crystalline polymer
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Herein, we report a crystalline CoTcPP-based [TcPP = the anion of meso-tetra(4-carboxyphenyl)porphyrin] polymeric system, 1, as a hydrogen evolution reaction (HER) electrocatalyst in acidic aqueous media. The material was characterized by powder X-ray diffraction (p-XRD), Fourier transform infrared (FT-IR) spectroscopy, and energy dispersive X-ray (EDX) analysis and its morphology was probed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Polymer 1 shows a surface area of 441.74 m3 g-1, while the discrete CoTcPP molecule (2) shows a surface area of 3.44 m3 g-1. The HER catalytic performance was evaluated by means of linear sweep voltammetry in the presence of 0.5 M H2SO4 aqueous solution. To achieve 10 mA cm-2 cathodic current density, 1 and 2 respectively require an overpotential of 0.475 V and 0.666 V, providing strong evidence that the extended network of cobalt-based porphyrin leads to enhanced HER efficiency. The polymer also shows great tolerance for HER electrolysis in the presence of an acid remaining active over 10 hours.
- Wu, Yanyu,Veleta, José M.,Tang, Diya,Price, Alex D.,Botez, Cristian E.,Villagrán, Dino
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- Visible-Light Photoreduction of CO2 in a Metal-Organic Framework: Boosting Electron-Hole Separation via Electron Trap States
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It is highly desirable to convert CO2 to valuable fuels or chemicals by means of solar energy, which requires CO2 enrichment around photocatalysts from the atmosphere. Here we demonstrate that a porphyrin-involved metal-organic framework (MOF), PCN-222, can selectively capture and further photoreduce CO2 with high efficiency under visible-light irradiation. Mechanistic information gleaned from ultrafast transient absorption spectroscopy (combined with time-resolved photoluminescence spectroscopy) has elucidated the relationship between the photocatalytic activity and the electron-hole separation efficiency. The presence of a deep electron trap state in PCN-222 effectively inhibits the detrimental, radiative electron-hole recombination. As a direct result, PCN-222 significantly enhances photocatalytic conversion of CO2 into formate anion compared to the corresponding porphyrin ligand itself. This work provides important insights into the design of MOF-based materials for CO2 capture and photoreduction.
- Xu, Hai-Qun,Hu, Jiahua,Wang, Dengke,Li, Zhaohui,Zhang, Qun,Luo, Yi,Yu, Shu-Hong,Jiang, Hai-Long
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- Control of Listeria innocua biofilms by biocompatible photodynamic antifouling chitosan based materials
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New materials obtained through the incorporation of meso-tetraarylporphyrins, bearing phenyl or pentafluorophenyl groups at the meso positions with or without acid groups, in chitosan films have been prepared and characterized in detail. The efficiency of these porphyrinic-chitosan films (PS-CF) to prevent Listeria innocua attachment and subsequent biofilm formation was evaluated under different irradiation protocols (dark, light, light + dark, dark + light). All tested porphyrinic-chitosan films were photostable and effective in reducing Listeria innocua attachment during a period of 24 h exposure to white light. Biofilm development was nearly completely inhibited in two of the PS-CF films (one containing the 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin and the other one of the thio-carboxylate porphyrins) after being exposed to white light for 24 h followed by incubation in the dark for 48 h. Experiments with the non-immobilized porphyrins against cell suspensions of the same Listeria innocua strain showed that, the photodynamic inactivation efficiency was dependent on porphyrin. The demonstrated antimicrobial activity of PS-CF films, associated with the easy recovery of these films, make them promising photodynamic antifouling materials.
- Castro, Kelly A.D.F.,Moura, Nuno M.M.,Fernandes, Ana,Faustino, Maria A.F.,Sim?es, Mário M.Q.,Cavaleiro, José A.S.,Nakagaki, Shirley,Almeida, Adelaide,Cunha, ?ngela,Silvestre, Armando J.D.,Freire, Carmem S.R.,Pinto, Ricardo J.B.,Neves, Maria da Gra?a P.M.S.
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- A porphyrin cobalt(II) complex linked to a TiO2/BiVO4 nanocomposite: Alcohol oxidation using nanohybrid materials as a photocatalyst: Via a mechanism approach
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Herein, a new nanohybrid catalyst was synthesized via covalently linking a tetraacetate porphyrin cobalt(ii) complex to a TiO2/BiVO4 nanocomposite, and its photocatalytic efficiency towards alcohol oxidation under visible light irradiation was monitored by GC. This nanohybrid material was implemented as a photocatalyst and characterized by the following physicochemical techniques: FE-SEM imaging, EDS, XRD, DRS, BET analysis, and FTIR spectroscopy. Additionally, its role as a photocatalyst was evaluated using a mechanistic approach under aerobic conditions by changing several parameters such as solvent, substrate, oxidant, amount of catalyst, reaction temperature, and ratio of oxidant to substrate. The photocatalytic activity of this nanohybrid catalyst, with an average size of 24 nm, increased almost twice as compared to that of the TiO2/BiVO4 nanocomposite from 35% to 85% conversion, whereas the selectivity was 99%. A plausible mechanism was proposed. In fact, the cobalt porphyrin complex as a light sensitizer improves the photocatalytic activity through impregnation onto the TiO2 surface. The photocatalyst was reused several times without significant loss of its activity. Thus, this nanohybrid robust catalyst has excellent advantages such as facile synthesis, high activity and selectivity, and use of O2 and other environmentally friendly oxidants under mild conditions towards aldehyde production.
- Askari, Parvin,Mohebbi, Sajjad
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- A zinc sulfide-supported iron tetrakis (4-carboxyl phenyl) porphyrin catalyst for aerobic oxidation of cyclohexane
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Zinc sulfide-supported iron tetrakis (4-carboxyl phenyl) porphyrin (Fe TCPP/ZnS) was prepared and used for aerobic cyclohexane oxidation. X-ray diffraction, ultraviolet-visible spectroscopy and Fourier-transform infrared spectroscopy were carried out. The effects of oxygen pressure, reaction temperature, amount of iron tetrakis (4-carboxyl phenyl) porphyrin (Fe TCPP) and reaction time on the Fe TCPP/ZnS-catalyzed cyclohexane oxidation process were investigated. Fe TCPP/ZnS exhibited excellent activity for aerobic cyclohexane oxidation. Under optimal reaction conditions, the turnover number, cyclohexane conversion, cyclohexanone and cyclohexanol yields were 8.6 × 105, 64.9% and 24.4%, respectively. The stability of Fe TCPP was improved after immobilization on zinc sulfide (ZnS), and the catalyst maintained nearly original levels of activity after several reaction cycles.
- Jiang, Yue-Xiu,Su, Tong-Ming,Qin, Zu-Zeng,Huang, Guan
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- Synthesis and photocytotoxic activity of new chlorin-polyamine conjugates
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This paper reports the synthesis of new chlorin-polyamine conjugates designed to improve the targeting of cancer cells. Photocytotoxic activity of these photosensitizers was tested against human chronic myelogenous leukemia cells (K562) and compared to the effects of Photofrin II and chlorin e6.
- Garcia, Guillaume,Sol, Vincent,Lamarche, Francois,Granet, Robert,Guilloton, Michel,Champavier, Yves,Krausz, Pierre
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- Facile synthesis, photophysical and electrochemical redox properties of octa- and tetracarboxamidophenylporphyrins and the first example of amido-imidol tautomerism in porphyrins
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5,10,15,20-tetrakis(4′-carboxamidophenyl)porphyrin (1) and 5,10,15,20-tetrakis(3′,5′-dicarboxamidophenyl)porphyrin (2) have been synthesized in excellent yields and characterized by various spectroscopic techniques and cyclic voltammetric studies. Notably, 1 and 2 exhibited amido-imidol tautomerism in DMSO-d6. The imido tautomer ([sbnd]C(OH)[dbnd]NH) was stabilised in DMSO-d6 at 293?K while the same was converted into amido form ([sbnd]CONH2) at high temperature (418?K). This is a first example of amido-imidol tautomerism in porphyrins. The moderate electron withdrawing nature of imidol groups at meso-phenyl rings lead to 80–95?mV anodic shift in their first ring reduction potential whereas 50–110?mV anodic shift in first ring oxidation potential as compared to that of H2TPP.
- Yadav, Pinky,Sankar, Muniappan
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- Modulating the Acidic and Basic Site Concentration of Metal-Organic Framework Derivatives to Promote the Carbon Dioxide Epoxidation Reaction
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Metal-organic framework (MOF) is an ideal precursor/template for porous carbon, and its active components are uniformly doped, which can be used in energy storage and catalytic conversion fields. Metal-organic framework PCN-224 with carboxylporphyrin as t
- Ji, Jinhua,Liu, Hao,Chen, Zewei,Fu, Yajun,Yang, Weijun,Yin, Shuang-Feng
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- N-confused porphyrin possessing glucamine-appendants: Aggregation and acid/base properties in aqueous media
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A water-soluble derivative of N-confused porphyrin (NCP: 5,10,15,20-tetraaryl-2-aza-21-carbaporphyrin) was synthesized by introducing glucamine groups at the para-position of meso-aryl groups. The tetraglucamine-appended NCP (TG-NCP) exists as monocation in aqueous solution containing 6 mM sodium dodecyl sulfate (SDS) but exists as freebase to form aggregates in pure water. These properties are distinct from those of corresponding regular porphyrin, which exists as freebase in the micellar solution and practically insoluble in water.
- Ikawa, Yoshiya,Ogawa, Hiroaki,Harada, Hiroyuki,Furuta, Hiroyuki
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- Straightforward synthesis of a porous chromium-based porphyrinic metal-organic framework for visible-light triggered selective aerobic oxidation of benzyl alcohol to benzaldehyde
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Among MOFs, chromium-based metal–organic frameworks (Cr-MOFs) represent attractive scaffolds for variety of potential applications due to their high porosity and stability. Nevertheless, Cr-MOFs are not very common due to complicate synthesis. Cr-MOFs of large linkers are one clear example of synthetic limitations, since their preparation takes place by post-synthetic routes, commonly starting from Fe-MOFs as precursors. Hence, in this work, the direct synthesis of a phorphyrinic chromium-based MOF, Cr-PCN-600 (PCN stands for Porous Coordination Network) under solvothermal conditions is reported. The resulting Cr-MOF exhibits high surface area, permanent porosity, and broad light absorption wavelength range. Interestingly, this Cr-MOF is a highly effective heterogeneous photocatalyst for the selective aerobic oxidation of benzyl alcohol to benzaldehyde under visible light irradiation without any additive. Importantly, the Cr-MOF showed good recyclability maintaining its activity for three runs. The present results lay the foundation for both synthesis and applications of Cr-MOFs as robust photocatalysts in advanced organic transformations. Notably, quenching studies confirmed the generation of superoxide radical anion (O2[rad]?) and singlet oxygen (1O2) (mostly) as reactive species under the reaction conditions.
- Daliran, Saba,García, Hermenegildo,Khajeh, Mostafa,Luque, Rafael,Oudi, Sara,Oveisi, Ali Reza,Sen, Unal
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- In situ self-assembly of zirconium metal-organic frameworks onto ultrathin carbon nitride for enhanced visible light-driven conversion of CO2 to CO
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A series of Zr-porphyrin metal-organic framework (Zr-PMOF)/ultrathin g-C3N4 (UCN) (ZPUCN) heterostructure photocatalysts, as stable and efficient catalysts for the photoreduction of CO2, have been fabricated via a facile in situ hydrothermal self-assembly method. An interfacial interaction is formed due to hollow Zr-PMOF nanotubes being surrounded by 3D ultrathin g-C3N4 (UCN) and benefiting from the ultrathin and conjugated π-structure of UCN, the unsaturated metal atoms and organic ligands of Zr-PMOFs can covalently link to organic g-C3N4. The interaction provides a platform for UCN as a conductor to transfer e- or as a donor to transfer e- to Zr-O cluster active sites to catalyze CO2, substantially achieving the spatial separation of charge carriers and suppressing the photogenerated electron-hole (e--h+) pair recombination rate. Benefitting from the cooperative effects of the well-designed nanostructure and chemical grafting, in the absence of triethanolamine, cocatalysts and photosensitizers, the optimized ZPUCN hybrid not only exhibits a better CO evolution yield (5.05 μmol g-1 h-1), which is 2.2 times and 3.2 times higher than those of pure Zr-PMOFs and UCN, respectively, but also displays excellent stability after 96 h photocatalysis. Information about the mechanism is also elucidated from selected characterizations.
- Guo, Haiwei,Wan, Shipeng,Wang, Yanan,Zeng, Yiqing,Zhang, Shule,Zhen, Wenlong,Zhong, Qin
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- Ruthenium-porphyrin conjugates with cytotoxic and phototoxic antitumor activity
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We report here two novel extended-arms porphyrins, TetbpyPP and TedabpyPP, in which four peripheral bpy fragments are connected to the meso positions of the macrocycle through flexible linkers of different length and hydrophilicity. We describe also the new, water-soluble, tetracationic conjugate [TedabpyPP{Ru([9]aneS3)Cl}4][Cl]4 (6). Compound 6 belongs to the series of cationic Ru-porphyrin conjugates 1-5, each bearing four peripheral Ru(II) half-sandwich coordination compounds, that we recently prepared as potential photosensitizing chemotherapeutic agents. The in vitro cell growth inhibition of conjugates 1-6 toward MDA-MB-231 human breast cancer cells and HBL-100 human nontumorigenic epithelial cells are reported, together with the phototoxic effects of 1, 4, and 6 on MDA-MB-231 cells. All conjugates have IC50 values in the low micromolar range that decrease by 1 order of magnitude upon irradiation of cell cultures with visible light. The most promising compounds 1 and 6 are phototoxic at low light and drug doses.
- Gianferrara, Teresa,Bergamo, Alberta,Bratsos, Ioannis,Milani, Barbara,Spagnul, Cinzia,Sava, Gianni,Alessio, Enzo
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- Extra Unsaturated Metal Centers of Zirconium-Based MOFs: a Facile Approach towards Increasing CO2 Uptake Capacity at Low Pressure
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Developing adsorption materials to capture CO2 at low pressure has attracted great attention due to the low CO2 partial pressure in fuel gases. Herein, zirconium-based metal–organic frameworks (PCN-X) are successfully synthesized and open metal sites (Fe3+ and Al3+) are incorporated into the PCN-X MOFs. The results indicate that the CO2 adsorption capability is enhanced through the strong interaction between extra open metal centers and CO2 molecules at low pressure. Meanwhile, the CO2 adsorption capacity of PCN-X with incorporated Al3+ is higher than with incorporated Fe3+, which can be attributed to the higher isosteric heat of CO2 adsorption. The adsorption kinetics further indicate the faster CO2 transmission on PCN-X with extra Al3+ than with extra Fe3+. Besides, modified PCN-X, treated by some inorganic acids, exhibits favorable chemical stability, which is suitable for CO2 capture from acidic fuel gases.
- Li, Zhong,Li, Xue,Chen, Chong,Zhou, Lijin,Guo, Qirui,Yuan, Dashui,Wan, Hui,Ding, Jing,Guan, Guofeng
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- Synthesis of Novel Porphyrin Derivatives with Mesogenic Properties
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Two novel porphyrin derivatives, 5,10,15,20-tetra(4-(N-octane-carboxamide)phenyl)porphyrin (4NC8-TPP) and 5,10,15,20-tetra(4-(N-stearyl-carboxamide)phenyl)porphyrin (4NC18-TPP), were synthesized. Their molecular structures were characterized by means of time-of-flight mass spectrometer (TOF-MS), nuclear magnetic resonance (NMR), and infrared spectra (IR). The thermal behavior and morphologies of 4NC8-TPP and 4NC18-TPP were examined by thermal gravity (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and polarizing optical microscope (POM). It was found that both 4NC8-TPP and 4NC18-TPP had mesogenic properties.
- Zhang, Xiaoyuan,Zhu, Biaobiao,Zhou, Li,Liu, Ping,Deng, Wenji
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- From Metal–Organic Frameworks to Single-Atom Fe Implanted N-doped Porous Carbons: Efficient Oxygen Reduction in Both Alkaline and Acidic Media
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It remains highly desired but a great challenge to achieve atomically dispersed metals in high loadings for efficient catalysis. Now porphyrinic metal–organic frameworks (MOFs) have been synthesized based on a novel mixed-ligand strategy to afford high-content (1.76 wt %) single-atom (SA) iron-implanted N-doped porous carbon (FeSA-N-C) via pyrolysis. Thanks to the single-atom Fe sites, hierarchical pores, oriented mesochannels and high conductivity, the optimized FeSA-N-C exhibits excellent oxygen reduction activity and stability, surpassing almost all non-noble-metal catalysts and state-of-the-art Pt/C, in both alkaline and more challenging acidic media. More far-reaching, this MOF-based mixed-ligand strategy opens a novel avenue to the precise fabrication of efficient single-atom catalysts.
- Jiao, Long,Wan, Gang,Zhang, Rui,Zhou, Hua,Yu, Shu-Hong,Jiang, Hai-Long
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- Mg–Al layered double hydroxide intercalated with manganese(III) 5,10,15,20-tetrakis(4-benzoate)porphyrinacetate as a highly reusable catalyst for epoxidation
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The preparation and characterization are presented of a new catalytic material comprising Mg–Al layered double hydroxide and intercalated manganese(III) 5,10,15,20-tetrakis(4-benzoate)porphyrinacetate. Characterization was realized via various techniques. The prepared composite exhibited excellent catalytic activity in the selective epoxidation of various olefins with tetra-n-butylammonium hydrogen monopersulfate as an oxidant under mild reaction conditions. Furthermore, the catalytic system could be reused nine times without significant reduction in conversion percentage and any special care or additional treatment of the catalyst.
- Bagherzadeh, Mojtaba,Mesbahi, Elnaz
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- Metalloporphyrins as chemical shift reagents: the unambiguous NMR characterization of the cis- and trans-isomers of meso-(bis)-4′-pyridyl-(bis)-4′-carboxymethylphenylporphyrins
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The condensation of pyrrole with 4-pyridylcarboxyaldehyde and methyl 4-formyl benzoate under Adler-Longo conditions yielded the series of meso-(4′-pyridyl)/(4′-carboxymethylphenyl)porphyrins as a mixture. Careful column chromatography afforded each isomer in pure form. In this paper we focus on the two bis-substituted isomeric meso-porphyrins, 5,10-bis(4′-pyridyl)-15,20-bis(4′-carboxymethylphenyl)porphyrin and 5,15-bis(4′-pyridyl)-10,20-bis(4′-carboxymethylphenyl)porphyrin, respectively, 4′-cis and 4′-transDPyDMeP. The assignment of the geometry of the two isomers was performed by 1H NMR spectroscopy on the trinuclear adducts [(4′-cisDPyDMeP){Ru(TPP)(CO)}2] and [(4′-transDPyDMeP){Ru(TPP)(CO)}2], obtained by selective coordination of [Ru(TPP)(CO)(EtOH)] (TPP=tetraphenylporphyrin) to the peripheral nitrogen atoms. The axially bound ruthenium porphyrins act as chemical shift reagents on the central porphyrin, allowing a clear distinction of the pyrrole proton resonances and consequent unambiguous assignment of the geometry of each isomer based upon symmetry considerations.
- Gianferrara, Teresa,Giust, Davide,Bratsos, Ioannis,Alessio, Enzo
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- Visible light production of superoxide anion with MCarboxyphenylporphyrins (M = H, Fe, Co, Ni, Cu, and Zn) free and anchored on TiO2: EPR characterization
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Metal carboxyphenylporphyrins: TcPPM, M = H, Fe, Co, Ni, Cu, and Zn, free and anchored on TiO2 were synthesized and characterized. The EPR spectra of TcPPH, TcPPCo, TcPPNi and TcPPZn exhibited only one line attributed to free radicals. For TcPPCu, the spin Hamiltonian parameters were accurately determined: g// = 2.186; g⊥ = 2.055; A// = 183 Gauss; A⊥ = 8 Gauss and A'Cu-N ～ 16 Gauss. A higher level protocol, UB3LYP/6-31G(df), was applied in order to obtain accurate values of the isotropic hyperfine coupling constants (hfccs), it showed excellent agreement with experimental results. Degradation of luminol, with and without radical scavengers (SOD, Mannitol and NaN3) indicated the presence of the superoxide anion (O2-), produced by the interaction of O2 with the conduction band electrons (e -CB), generated by photosensitization (λ > 420 nm) of TiO2 with the porphyrin dye. The TcPPM/TiO2 were more efficient (generation of O2-) than the TcPPM in solution as evidenced by the degradation of luminol under visible light perhaps due to site isolation preventing the formation of photo-inactive dimers.
- Granados-Oliveros, Gilma,Páez-Mozo, Edgar Alberto,Martínez Ortega, Fernando,Piccinato, Marileneturini,Silva, Fausto Neves,Guedes, Carmen Luísa Barbosa,Di Mauro, Eduardo,Costa, Marcello Ferreira Da,Ota, André Tsutomu
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- Nanoscale Synthesis of Two Porphyrin-Based MOFs with Gallium and Indium
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Two porphyrin-based metal-organic frameworks (MOFs) containing gallium or indium, [Ga2(OH)2(H2TCPP)]·3DMF·3H2O (Ga-PMOF) and [In2(OH)2(H2TCPP)]·3DMF·4H2O (In-PMOF) (H6TCPP = 4-tetracarboxyphenylporphyrin), were discovered using high-throughput methods. The structure was refined by the Rietveld-method starting from the structure model of Al-PMOF, [Al2(OH)2(H2TCPP)]. The new PMOFs exhibit BET surface areas between 1150 and 1400 m2 g-1 and are also porous toward CO2 (Ga-PMOF, 15.2 wt %; In-PMOF, 12.9 wt %). They are thermally stable in air up to 330 °C, but show limited chemical stabilities toward acids and bases. In order to achieve size control, different synthesis routes were investigated, i.e., batch synthesis at different temperatures (yield: In-PMOF-bs-th 96%, Ga-PMOF-bs-th 87%), ultrasound-assisted synthesis (yield: In-PMOF-bs-us 85%), and continuous-flow synthesis (yield: Ga-PMOF-cf 71%). By using these different methods we could control the nucleation rate and the crystal size. The crystal sizes were found to vary about 60 to 160 nm and 70 to 130 nm for Ga- and In-PMOF, respectively, which was proven by dynamic light scattering (DLS), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) measurements.
- Rhauderwiek, Timo,Waitschat, Steve,Wuttke, Stefan,Reinsch, Helge,Bein, Thomas,Stock, Norbert
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- A simple strategy for engineering heterostructures of Au nanoparticle-loaded metal-organic framework nanosheets to achieve plasmon-enhanced photocatalytic CO2 conversion under visible light
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Carbon dioxide selectively concentrated in micropores of metal-organic frameworks (MOFs) and light absorption units as bridged ligands or guest molecules incorporated into MOF matrices are positive effects on upgrading reactivity of metal catalytic centers towards CO2 conversion through high-efficient quasi-intramolecular electron transfer among them. However, in contrast to the surfaces of MOFs, sluggish mass transfer of CO2, as well as of products, in micropores could negatively affect photocatalytic activity for CO2 reduction. Moreover, interactions between light and matter are heavily blocked if light absorption units are buried deep in bulky MOF matrices. In this research, hybrids of thin porphyrin paddle-wheel framework-3 (PPF-3) nanosheets (PPF-3-1) anchored with AuNPs are prepared by an electrostatic interaction to address these questions. This mainly involves improvement of PPF-3 morphology and the assembly mode between Au nanoparticles (AuNPs) and PPF-3 nanosheets. On the one hand, thin nanosheets can induce faster charge transfer rate and higher mass transport capability than thick nanosheets in the photocatalytic process; on the other hand, plasmonic AuNPs loaded onto the surfaces of nanosheets lead to more effective light absorption than AuNPs encapsulated in the matrices of nanosheets. Finally, the hybrids exhibit superior photocatalytic activity for CO2 conversion into HCOOH in an acetonitrile/ethanol system by plasmon resonance energy transfer process compared with pure PPF-3-1 or hybrids of thick PPF-3 nanosheets (PPF-3-2) supporting AuNPs. The research offers a novel and universal strategy to build high-efficiency MOF-based photocatalysts with enhanced performance for selective photocatalytic CO2 reduction.
- Chen, Liyong,Wang, Yanxin,Yu, Fengyang,Shen, Xiaoshuang,Duan, Chunying
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- Porphyrinic Metal-Organic Framework Catalyzed Heck-Reaction: Fluorescence "turn-On" Sensing of Cu(II) Ion
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It is of great importance for the highly selective, rapid, and sensitive detection of Cu(II) ion, as copper is an essential element in the environment and the human body, and exposure to high concentrations of Cu(II) will potentially cause health issues. In this work, we have developed a novel catalytic Heck reaction system based on Pd(II)-porphyrinic metal-organic framework (MOF), PCN-222-Pd(II), to generate highly fluorescent product in the presence of Cu(II). In this system, the achieved signal enlargement toward Cu(II) with high sensitivity not only takes advantage of a stronger binding affinity of Cu(II) over Pd(II) to the nitrogen atoms in the porphyrin, but also a rapid Pd(0)-catalyzed Heck-reaction triggered by the addition of Cu(II) ion. Compared with the previous detection methods, the current fluorescence "turn-on" approach not only realizes highly selective and sensitive detection of Cu(II) in aqueous solution, but also is able to separate the Cu(II) from the system. This work would open up a new door for MOF applications in the detection of metal ions in complex environments.
- Chen, Yu-Zhen,Jiang, Hai-Long
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- Redox-responsive porphyrin-based polysilsesquioxane nanoparticles for photodynamic therapy of cancer cells
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The development of stimulus-responsive photosensitizer delivery systems that carry a high payload of photosensitizers is of great importance in photodynamic therapy. In this study, redox-responsive polysilsesquioxane nanoparticles (PSilQNPs) built by a reverse microemulsion approach using 5,10,15,20-tetrakis(carboxyphenyl) porphyrin (TCPP) silane derivatives as building blocks, were successfully fabricated. The structural properties of TCPP-PSilQNPs were characterized by dynamic light scattering (DLS)/ζ-potential, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The photophysical properties were determined by UV-vis and fluorescence spectroscopy. The quantity of singlet oxygen generated in solution was measured using 1,3-diphenylisobenzofuran. The redox-responsive release of TCPP molecules was successfully demonstrated in solution in the presence of a reducing agent. The internalization of TCPP-PSilQNPs in cancer cells was investigated using laser scanning confocal microscopy. Phototoxicity experiments in vitro showed that the redox-responsive TCPP-PSilQNPs exhibited an improved phototherapeutic effect on cervical cancer cells compared to a non-responsive TCPP-PSilQNP control material.
- Vega, Daniel L.,Lodge, Patrick,Vivero-Escoto, Juan L.
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- MOF/PEDOT/HPMo-based polycomponent hierarchical hollow micro-vesicles for high performance flexible supercapacitors
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Metal-organic frameworks (MOFs) are promising electrode materials for supercapacitors; however, their electrochemical performances are limited by their low electrical conductivities. To address this problem, “conductive ink” poly(3,4-ethylenedioxythiophene) (PEDOT) was used to enhance the conductivity, while “electron sponge” polyoxometalate [PMo12O40]3?(PMo12) with large electronic transfer capability was used as the capacitance contributor. Finally, MOFs (PCN-224) acted as the host of this composite that provided the electrical double-layer capacitor and a PCN-224@PEDOT/PMo12-CC-II hierarchical hollow micro-vesicle nanostructure was obtainedviaa simple one-step electro-codeposition. The microvesicle nanocomposite was interspersed in MOF hosts. Benefiting from the novel structure and the synergistic effect of three components, the optimal areal capacitance of the PCN-224@PEDOT/PMo12-CC-II electrode was 4077.8 mF cm?2at 5 mA cm?2(the concentration ratio of EDOT?:?PMo12is 1?:?0.75), which is 32.9 times more than that of pristine PCN-224 (123.6 mF cm?2). Furthermore, a symmetric supercapacitor device was constructed by the PCN-224@PEDOT/PMo12-CC-II nanocomposite, which possessed an excellent energy density of 0.297-0.0192 mW h cm?2(at a power density of 0.324-5.128 W cm?2) and a good long-term cycle ability (84.59% for 10?000 cycles at 5 mA cm?2). This study presented a one-step electro-deposition synthetic strategy for the design and fabrication of the high-capacitance MOF-based electrode material, which showed great promise in the future design of high-performance materials for advanced energy production.
- Wang, Bing,Liu, Shuo,Liu, Lin,Song, Wen-Wei,Zhang, Yue,Wang, Shi-Ming,Han, Zheng-Bo
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- An Efficient Catalyst Based on a Metal Metalloporphyrinic Framework for Highly Selective Oxidation
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An efficient metal-organic framework catalyst was developed with manganese tetrakis(4-carboxyphenyl)porphyrin as either bridging moiety or catalytically active sites under a hydrothermal condition. Surprisingly, the X-ray diffraction details showed that this porous network, MMPF (MMPF denotes iron-connected metal metalloporphyrinic framework) was successfully constructed with a physically flexible framework and resistance to basic solution. Accordingly, catalytic studies have demonstrated that MMPF can catalyze the selective oxidation of a variety of substrates with PhIO as oxidant in acetonitrile solution under mild temperature. More importantly, the MMPF outperformed the homogeneous Mn-TPP in catalyzing epoxidation of cyclohexene, mainly due to its high efficiency of 3D network-based nanochannel-reactor in MMPF. This gave rise to a structural resistance to formation of catalytically inactive species. Graphical Abstract: [Figure not available: see fulltext.]
- Zhang, Weijie,Jiang, Pingping,Wang, Ying,Zhang, Jian,Zhang, Pingbo
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- Metal–Organic Frameworks for the Exploitation of Distance between Active Sites in Efficient Photocatalysis
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Discoveries of the accurate spatial arrangement of active sites in biological systems and cooperation between them for high catalytic efficiency are two major events in biology. However, precise tuning of these aspects is largely missing in the design of artificial catalysts. Here, a series of metal–organic frameworks (MOFs) were used, not only to overcome the limit of distance between active sites in bio-systems, but also to unveil the critical role of this distance for efficient catalysis. A linear correlation was established between photocatalytic activity and the reciprocal of inter active-site distance; a smaller distance led to higher activity. Vacancies created at selected crystallographic positions of MOFs promoted their photocatalytic efficiency. MOF-525-J33 with 15.6 ? inter active-site distance and 33 % vacancies exhibited unprecedented high turnover frequency of 29.5 h?1 in visible-light-driven acceptorless dehydrogenation of tetrahydroquinoline at room temperature.
- Deng, Hexiang,Gong, Xuan,Jiang, Zhuo,Lu, Lingxiang,Shu, Yufei,Wang, Chao,Xu, Xiaohui
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- Photodynamic effect of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin and (Zn2+ and Sn4+) derivatives against Leishmania spp in the promastigote stage: experimental and DFT study
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In this work, we synthesized the meso-(aryl) porphyrin derivative 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) and two meso-(aryl) metalloporphyrins, TCPP-Zn(II) and TCPP-Sn(IV), with reaction yields between 33.91 and 80.4%. The photophysical properties were determined, and the in vitro photodynamic properties were evaluated against Leishmania spp in the promastigote stage. The TCPP-Zn(II) reduced the viability of the parasites as shown by the lowest IC50, which is even lower than the reference drug glucantime. In general, our results indicate that the beneficial effect related to the lethal capacity of porphyrins was greater in the presence of light irradiation. Furthermore, the inclusion of a diamagnetic metal such as Zn(II) is essential for the biological properties shown by this type of compounds, as it substantially improves their photodynamic activity. The Jablonsky diagrams were proposed using DFT computations, where the decay channels through the ground and excited states were assessed and the feasible generation of singlet oxygen was established, being TCPP-Zn(II) the one that shows a slightly more exothermic process than TCPP-Sn(IV).
- Espitia-Almeida, Fabián,Díaz-Uribe, Carlos,Vallejo, William,Pe?a, Orlando,Gómez-Camargo, Doris,Bohórquez, Arnold R. Romero,Zarate, Ximena,Schott, Eduardo
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- Metal–Organic Framework-Derived FeCo-N-Doped Hollow Porous Carbon Nanocubes for Electrocatalysis in Acidic and Alkaline Media
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Metal–organic frameworks (MOFs) are ideal precursors/ templates for porous carbons with homogeneous doping of active components for energy storage and conversion applications. Herein, metalloporphyrinic MOFs, PCN-224-FeCo, with adjustable molar ratio of FeII/CoII alternatively residing inside the porphyrin center, were employed as precursors to afford FeCo-N-doped porous carbon (denoted as FeCo-NPC) by pyrolysis. Thanks to the hollow porous structure, the synergetic effect between highly dispersed FeNx and CoNx active sites accompanied with a high degree of graphitization, the optimized FeCo2-NPC-900 obtained by pyrolysis at 900 °C exhibits more positive half-wave potential, higher diffusion-limited current density, and better stability than the state-of-the-art Pt/C, under both alkaline and acidic media. More importantly, the current synthetic approach based on MOFs offers a rational strategy to structure- and composition-controlled porous carbons for efficient electrocatalysis.
- Fang, Xinzuo,Jiao, Long,Yu, Shu-Hong,Jiang, Hai-Long
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- Rapid and specific luminescence sensing of Cu(II) ions with a porphyrinic metal-organic framework
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We herein present a porphyrinic metal-organic framework (MOF) as a highly sensitive fluorescent probe targeting Cu(ii) ions with a fast response. The well-isolated nature of porphyrin moieties within the framework greatly enable accessible recognition sites, which leads to an outstanding detection limit performance of 67 nM among MOF-based materials.
- Li, Linnan,Shen, Sensen,Lin, Ruoyun,Bai, Yu,Liu, Huwei
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- Enhanced Photodynamic Therapy by Reduced Levels of Intracellular Glutathione Obtained By Employing a Nano-MOF with CuII as the Active Center
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In photodynamic therapy (PDT), the level of reactive oxygen species (ROS) produced in the cell directly determines the therapeutic effect. Improvement in ROS concentration can be realized by reducing the glutathione (GSH) level or increasing the amount of photosensitizer. However, excessive amounts photosensitizer may cause side effects. Therefore, the development of photosensitizers that reduce GSH levels through synergistically improving ROS concentration in order to strengthen the efficacy of PDT for tumor is important. We report a nano-metal–organic framework (CuII-metalated nano-MOF {CuL-[AlOH]2}n (MOF-2, H6L=mesotetrakis(4-carboxylphenyl)porphyrin)) based on CuII as the active center for PDT. This MOF-2 is readily taken up by breast cancer cells, and high levels of ROS are generated under light irradiation. Meanwhile, intracellular GSH is considerably decreased owing to absorption on MOF-2; this synergistically increases ROS concentration and accelerates apoptosis, thereby enhancing the effect of PDT. Notably, based on the direct adsorption of GSH, MOF-2 showed a comparable effect with the commercial antitumor drug camptothecin in a mouse breast cancer model. This work provides strong evidence for MOF-2 as a promising new PDT candidate and anticancer drug.
- Zhang, Wei,Lu, Jun,Gao, Xiaonan,Li, Ping,Zhang, Wen,Ma, Yu,Wang, Hui,Tang, Bo
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- A novel drug-drug nanohybrid for the self-delivery of porphyrin and: Cis-platinum
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The thriving development of nanotechnology has greatly promoted the development of drug delivery systems (DDSs) in the past decades. However, most DDSs themselves cannot serve as diagnostic reagents and must be metabolized, by which they may become poisonous and even cause immune reactions. In this study, a novel self-delivery drug-drug system (SDDS) nanohybrid based on the coordination assembly of a photodynamic reagent, tetra-(4-carboxyphenyl)porphyrin (TCPP), and a chemotherapy reagent, cis-platinum, was designed and synthesized. The four carboxyl groups of TCPP can compete with the chloride ions of cis-platinum by coordination interactions, forming a TCPP-cis-platinum nanohybrid (PCNH) for the purpose of photodynamic/chemotherapeutic synergistic treatment with a combinational index of 0.28. Meanwhile, the PCNH system can effectively protect the photosensitizer TCPP from photobleaching when irradiated continuously in the photodynamic therapy (PDT) process, which is very crucial for PDT. Furthermore, introduction of the heavy atom platinum can greatly enhance the producing efficiency of 1O2 by 46%. In addition, the red emission fluorescence of TCPP is beneficial for monitoring and tracing the process of drug delivery when used in vitro. This work may pave a new way for the design of new integrated nanohybrids for diagnosis and synergistic treatment.
- Shan, Changfu,Ru, Jiaxi,Zhang, Meina,Cao, Jing,Liu, Weisheng,Guo, Huichen,Tang, Yu
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- Neutral Porphyrin Derivative Exerts Anticancer Activity by Targeting Cellular Topoisomerase i (Top1) and Promotes Apoptotic Cell Death without Stabilizing Top1-DNA Cleavage Complexes
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Camptothecin (CPT) selectively traps topoisomerase 1-DNA cleavable complexes (Top1cc) to promote anticancer activity. Here, we report the design and synthesis of a new class of neutral porphyrin derivative 5,10-bis(4-carboxyphenyl)-15, 20-bis(4-dimethylaminophenyl)porphyrin (compound 8) as a potent catalytic inhibitor of human Top1. In contrast to CPT, compound 8 reversibly binds with the free enzyme and inhibits the formation of Top1cc and promotes reversal of the preformed Top1cc with CPT. Compound 8 induced inhibition of Top1cc formation in live cells was substantiated by fluorescence recovery after photobleaching (FRAP) assays. We established that MCF7 cells treated with compound 8 trigger proteasome-mediated Top1 degradation, accumulate higher levels of reactive oxygen species (ROS), PARP1 cleavage, oxidative DNA fragmentation, and stimulate apoptotic cell death without stabilizing apoptotic Top1-DNA cleavage complexes. Finally, compound 8 shows anticancer activity by targeting cellular Top1 and preventing the enzyme from directly participating in the apoptotic process.
- Das, Subhendu K.,Ghosh, Arijit,Paul Chowdhuri, Srijita,Halder, Nyancy,Rehman, Ishita,Sengupta, Souvik,Sahoo, Krushna Chandra,Rath, Harapriya,Das, Benu Brata
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- Conformational-Switch Based Strategy Triggered by [18] π Heteroannulenes toward Reduction of Alpha Synuclein Oligomer Toxicity
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A water-soluble meso-carboxy aryl substituted [18] heteroannulene (porphyrin) and its Zn-complex have been found to be viable in targeting α-Syn aggregation at all its key microevents, namely, primary nucleation, fibril elongation, and secondary nucleation, by converting the highly heterogeneous and cytotoxic aggresome into a homogeneous population of minimally toxic off-pathway oligomers, that remained unexplored until recently. With the EC50 and dissociation constants in the low micromolar range, these heteroannulenes induce a switch in the secondary structure of toxic prefibrillar on-pathway oligomers of α-Syn, converting them into minimally toxic nonseeding off-pathway oligomers. The inhibition of the aggregation and the reduction of toxicity have been studied in vitro as well as inside neuroblastoma cells.
- Chakraborty, Ritobrita,Sahoo, Sumit,Halder, Nyancy,Rath, Harapriya,Chattopadhyay, Krishnananda
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- Porphyrin derivatives as potent and selective blockers of neuronal Kv1 channels
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Selective inhibitors of voltage-activated K+ channels are needed for the treatment of multiple sclerosis. In this work it was discovered that porphyrins bearing 2-4 carbon alkyl ammonium side chains predominantly blocked the Kv1.1 current whilst Kv1.2 was susceptible to a porphyrin bearing polyamine side chains.
- Daly,Al-Sabi,Kinsella,Nolan,Dolly
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- Porphyrin Antennas on Carbon Nanodots: Excited State Energy and Electron Transduction
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We report the synthesis and electron donor–acceptor features of a novel nanohybrid, in which the light-harvesting and electron-donating properties of a meso-tetraarylporphyrin (TArP) are combined with the electron-accepting features of nitrogen-doped carbon nanodots (NCNDs). In particular, in an ultrafast process (>1012 s?1), visible-light excitation transforms the strongly quenched porphyrin singlet excited states into short-lived (225 ps) charge-separated states. On the other hand, ultraviolet light excitation triggers a non-resolvable transduction of singlet excited state energy from the NCNDs to the porphyrins, followed by the same charge separation observed upon visible light excitation.
- Arcudi, Francesca,Strauss, Volker,?or?evi?, Luka,Cadranel, Alejandro,Guldi, Dirk M.,Prato, Maurizio
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- Synthesis of magnetite-porphyrin nanocomposite and its application as a novel magnetic adsorbent for removing heavy cations
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Magnetite-porphyrin nanocomposite (MPNC) was synthesized as a novel magnetic adsorbent for removing heavy cations. Firstly, we prepared nano-sized magnetite using a simple hydrothermal route. The synthesis of nanoscaled magnetite was carried out through reaction between iron source and various amines. In this paper, we studied effective parameters in controlling shape and size of nanoscaled magnetite. These parameters were presence of alkaline, reaction time, kind of amine and iron salt. Morphology, particle size and magnetic properties of the nanoscaled magnetite were obtained by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared (FT-IR), diffuse reflectance spectra (DRS) and vibrating sample magnetometer (VSM). Our study showed that the synthesized magnetite from reaction between FeSO4 and hydrazinum hydrate has spherical shape. The synthesized magnetite was a nanosized compound and used for preparation of magnetite-porphyrin nanocomposite. The synthesized magnetite-porphyrin hybrid material had magnetic property and was used as magnetic adsorbent for removing heavy cations of water. Satisfactory separation from solutions in the order of Pb2+ > Cd2+ > Hg 2+ was obtained.
- Bakhshayesh, Sara,Dehghani, Hossein
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- Cis -Decalin oxidation as a stereochemical probe of in-MOF versus on-MOF catalysis
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Development of catalyst-controlled C-H hydroxylation could provide direct access to valuable synthetic targets, such as primary metabolites. Here, we report a new family of porous materials, comprised of 2-dimensional metalloporphyrin layers and flexible aliphatic linkers, and demonstrate C-H hydroxylation activity. We demonstrate that the stereochemistry of cis-decalin oxidation provides a useful tool for differentiating catalysis in from catalysis on porous materials, which is critical to leveraging the potential of porous materials for catalyst-controlled oxidation chemistry.
- Cardenal, Ashley D.,Jeong Park, Hye,Chalker, Cody J.,Ortiz, Kacey G.,Powers, David C.
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- A spectroscopic and molecular docking study of interactions of tetracarboxyphenyl porphyrin and chlorin e6 with bovine serum albumin
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Abstract: In order to use tetrapyrrolic macrocyclic species in medical applications, the interactions of bovine serum albumin (BSA) with tetrakis-para-carboxyphenyl-porphyrin (H2T(p-COOH) PP or TCPP) and Chlorin e6 (Ce6), under different conditions, were investigated by fluorescence spectroscopy and UV–VIS absorption spectroscopy and contrasted with molecular docking study. The binding constant (Kb) values at three different temperatures were calculated using the modified Stern–Volmer equation. The enthalpy change (ΔH) and entropy change (ΔS) were determined based on the van’t Hoff equation. The results of fluorescence spectroscopy indicate that static quenching is the dominant process resulting from the BSA-TCPP complex formation. In the case of the BSA-Ce6 complex, static quenching was confirmed too. Thermodynamic analysis indicated that hydrogen bonds and van der Waals interactions were the predominant intermolecular forces in the binding process to stabilize the BSA-TCPP and BSA-Ce6 complexes. Molecular docking suggests that the probable binding site of the two macrocyclic species at BSA occurs in the vicinity of the Trp-134 residue. Molecular modeling study further confirmed interactions in the binding mode obtained experimentally. Graphic abstract: [Figure not available: see fulltext.]
- Vicente-Escobar, Jonathan Osiris,García-Sánchez, Miguel A.,González,Cipagauta-Díaz,Estrella González
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- A stable and highly selective metalloporphyrin based framework for the catalytic oxidation of cyclohexene
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A new metalloporphyrin framework of molybdenum Mo2O4(C48H28N4O8)·(CH3)2NH·5H2O·2DMF (Mo2TCPP) was synthesized from tetrakis(4-carboxyphenyl)porphyrin (H4TCPP) and sodium molybdate dihydrate by a hydrothermal method. Mo2TCPP is a 3D network with two sub-units, in which both TCPP ligands and each Mo2 dimer act as four connection nodes. The crystal structure was determined by single crystal analysis and further characterized by FTIR, SEM, EDX, PXRD, XPS and TGA. Here cumene hydrogen peroxide and hydrogen peroxide were used as oxidants to study the catalytic activity of new metalloporphyrins in the oxidation of cyclohexene at different temperatures. The conversion rate of cyclohexene and the selectivity of epoxycyclohexane were both higher than 99percent, which was better than the previously published research results. The stability of the catalyst before and after the reaction was further tested for 10 runs without obvious degradation. The catalyst was stable in different solutions such as acidic, water and alkaline. These results shed light on the future development of new catalytic materials based on metalloporphyrin.
- Feng, Pingyun,Li, Fengyan,Xia, Zhinan,Xu, Lin
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- Photocatalytic activity of nanohybrid Co-TCPP@TiO2/WO3 in aerobic oxidation of alcohols under visible light
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Here the photocatalytic performance activity of a novel Co-TCPP@TiO2/WO3 nanohybrid toward selective alcohol oxidation is reported. The Co-TCPP@TiO2/WO3 nanohybrid was prepared in three major steps. After the synthesis of nano-disk WO3 by a new green chemical method using natural pomegranate juice, a TiO2/WO3 nanocomposite was obtained via a sonochemical assisted hydrothermal method, followed by anchoring of cobalt(ii)-meso-tetra(4-carboxyphenyl)porphyrin (Co-TCPP) on TiO2/WO3. All intermediate nanomaterials and the final nanohybrid compound were characterized by FE-SEM, EDAX, XRD, DRS and FT-IR spectroscopy. The photocatalytic behavior of the TiO2/WO3 nanocomposite and Co-TCPP@TiO2/WO3 nanohybrid were investigated in oxidation of primary alcohols under visible light irradiation in the presence of air as the oxygen source. The progress of the catalytic reactions was monitored using a TLC technique. Remarkably, the photocatalytic performance of the TiO2/WO3 nanocomposite was enhanced from 70 to 95% by anchoring the TCPP on the composite. This nanohybrid catalyst was reused and recovered ten times without losing photocatalytic activity. In fact, nanohybrid Co-TCPP@TiO2/WO3 shows an extremely higher efficiency and shorter reaction time (1 h) than the TiO2/WO3 nanocomposite. So, this nanohybrid compound has the potential to be used as a high performance heterogeneous photocatalyst under visible light irradiation for oxidation reactions, with advantages of high activity, high selectivity, reusability and easy separation.
- Safaei, Elham,Mohebbi, Sajjad
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- Electrostatic core shielding in dendritic polyglutamic porphyrins
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Polyglutamic dendritic porphyrins of the general formula H2PophGlu(N)OR (H2Porph free-base meso-tetra-4- carboxyphenylporphyrin (H2TCPP), Glu = dendrimer layer composed of L-glutamates, N = 1-3: dendrimer generation number
- Vinogradov, Sergei A.,Wilson, David F.
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- Conjugates of platinum nanoparticles with gallium tetra - (4-Carboxyphenyl) porphyrin and their use in photodynamic antimicrobial chemotherapy when in solution or embedded in electrospun fiber
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The conjugation of Pt nanoparticles with ClGa(III) 5,10,15,20-tetrakis-(4- carboxyphenyl) porphyrin (ClGaTCPP) showed greater antimicrobial activity against a gram positive and drug resistant bacteria Staphylococcus aureus, than when the porphyrin was used alone. ClGaTCPP and its conjugate with platinum nanoparticle was successfully electrospun into a polystyrene polymer where the diameter ranged from 10 to 22 μm. The conjugates within the fiber still showed activity towards S. aureus.
- Managa, Muthumuni,Antunes, Edith,Nyokong, Tebello
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- Syntheses and energy transfer in multiporphyrinic arrays self-assembled with hydrogen-bonding recognition groups and comparison with covalent steroidal models
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A number of new porphyrins equipped with complementary triple hydrogen-bonding groups were synthesized in good yields. Self-assembly was investigated by NMR spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM). These artificial antenna systems were further characterized by stationary and time-resolved fluorescence techniques to investigate several yet unsolved questions on the mechanism of excitation energy transfer (EET) in supramolecular systems. For example, the photo-physics of a simple D - U≡P - A dyad was studied, in which donor D and acceptor A are ZnII- metalated and free-base porphyrins, respectively, and U (uracyl) and P (2,6-diacetamidopyridyl) are complementary hydrogen-bonding groups linked by flexible spacers. In this dyad, the EET occurs with about 20% efficiency with a lifetime of 14 ps. Reversal of the nonsymmetric triple hydrogen-bonding groups to give a A - U≡P - D construct results in an EET efficiency of about 25% and a lifetime of 19 ps. Thus, there is a slight directionality of EET mediated by these asymmetric triple hydrogen-bonding units tethered to flexible spacers. In polymeric systems of the type ...P-D-P≡U-A-U≡P-D-P..., or ...D-U≡P-A- P≡U-D-U..., the EET efficiency doubles as each donor is flanked by two acceptors. Because doubling the probability of photon capture doubles the EET efficiency, there is no energy amplification, which is consistent with the "antenna effect". For these polymeric systems, AFM images and DLS data indicate large rodlike assemblies of a few hundred nanometers, whereas the components form much smaller aggregates under the same conditions. To understand the importance of the flexible hydrogen-bonding zipper, three different covalently bridged D-B-A molecules were synthesized in which the bridge B is a rigid steroidal system and the same ester chemistry was used to link the porphyrins to each end of the steroid. The geometry inferred from molecular modeling of D-B-A indicates geometric similarities between B and some conformations of the -P≡U- supramolecular bridge. Although the EET efficiency is a factor of two greater for the steroidal systems relative to the supramolecular dyads, the rate is 50-80 times slower, but still slightly faster than that predicted by Foerster-type mechanisms. Circular dichrosim (CD) spectra provide a conformational sampling of the porphyrin groups appended on the steroidal skeleton, thus allowing an estimation of the orientation factor κ for the transition dipole moments, which significantly affects the EET rate. We conclude that the flexible hydrogen-bonded linked systems are adaptive and have variable geometries with foldamers in which the D and A groups can approach well under 1 nm. In these folded conformations, a rapid EET process occurs, probably also involving a Dexter-type exchange mechanism, thus explaining the fast EET relative to the rigid steroidal compounds. This study predicts that it is indeed possible to build large supramolecular antennas and the component design and supramolecular dynamics are essential features that dictate EET rates and efficiencies.
- Balaban, Teodor Silviu,Berova, Nina,Drain, Charles Michael,Hauschild, Robert,Huang, Xuefei,Kalt, Heinz,Lebedkin, Sergei,Lehn, Jean-Marie,Nifaitis, Fotis,Pescitelli, Gennaro,Prokhorenko, Valentyn I.,Riedel, Gernot,Smeureanu, Gabriela,Zeller, Joachim
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- DNA photocleavage by porphyrin-polyamine conjugates
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A series of polyamine-porphyrin conjugates bearing two (cis or trans position) or four units of spermidine or spermine was synthesized. We studied the binding of these cationic porphyrins to calf thymus DNA by the means of UV-vis spectroscopy and we investigated their ability to cleave plasmid DNA in the presence of light. DNA binding and DNA photocleavage abilities were found to depend on structural characteristics as (a) the relative positions of the side chains on the porphyrin ring and (b) the nature of the attached side chains (spermidine or spermine). DNA cleavage was also studied in the presence of a singlet oxygen quencher (NaN3) and in the presence of a hydroxyl radical scavenger (mannitol). Singlet oxygen was the major species responsible for the cleavage of DNA previously observed. Collectively, these data show that polyamine-porphyrin conjugates could be promising phototherapeutic agents.
- Garcia, Guillaume,Sarrazy, Vincent,Sol, Vincent,Morvan, Caroline Le,Granet, Robert,Alves, Sandra,Krausz, Pierre
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- Immobilization of Rh(i) precursor in a porphyrin metal-organic framework - turning on the catalytic activity
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Two model porphyrin metal-organic frameworks were used for the incorporation of Rh(i) species by a post-synthetic metallation under mild conditions. As a result, new rhodium MOFs (Rh/MOFs),Rh/PCN-222andRh/NU-1102, were synthesized and structurally characterized. To illustrate the potential of this catalytic platform, we use Rh/MOFs as phosphine-free heterogeneous catalysts in the hydrogenation of unsaturated hydrocarbons under mild reaction conditions (30 °C and 1 atm H2). We found that for our Rh/MOFs an activation step is required during the first run of the catalytic process. The presence of Rh-CO moieties allowed us to monitor the activation pathway of the catalyst under a H2atmosphere, byin situDiffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). After activation, the catalyst remains highly active during the subsequent catalytic cycles. This simple post-synthetic modification approach presents new possibilities for the utilization of Rh-based catalytic systems with robust porphyrin-based MOFs as supports.
- Bury, Wojciech,Janeta, Mateusz,Siczek, Mi?osz,Szczepkowska, Anna M.,Trzeciak, Anna M.,Tylus, W?odzimierz
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- Visible light superoxide radical anion generation by tetra(4-carboxyphenyl) porphyrin/TiO2: EPR characterization
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The generation of superoxide radical anion O2- from tetra(4-carboxyphenyl)porphyrin (TCPP) adsorbed on TiO2 in DMSO and irradiated by visible light was studied using EPR spectroscopy and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as spin trap. A chemical filter was used to remove light with wave lengths 2- and the second to the so-called nitroxide-like radical. Hyperfine coupling constants determined for the DMPO-O2 - adduct are: aN = 14.1 G, aHβ = 10.8 G and aHγ = 1.4 G, and for the nitroxide-like radical adduct aN = 14 G. An increased intensity of the EPR lines corresponding to the nitroxide-like radical adduct was observed under irradiation without chemical filter, which suggests a possible DMPO-O 2- decomposition. No singlet oxygen could be detected by EPR spectroscopy using 2,2,6,6-tetramethyl-4-piperidone (TEMP) as spin trap and by chemical trapping using anthracene as the trap.
- Diaz-Uribe, Carlos E.,Daza, Martha C.,Martínez, Fernando,Páez-Mozo, Edgar A.,Guedes, Carmen L.B.,Di Mauro, Eduardo
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- Selective oxidation of aromatic sulfide catalyzed by an artificial metalloenzyme: New activity of hemozymes
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Two new artificial hemoproteins or "hemozymes", obtained by non covalent insertion of Fe(III)-meso-tetra-p-carboxy- and -p-sulfonato- phenylporphyrin into xylanase A from Streptomyces lividans, were characterized by UV-visible spectroscopy and molecular modeling studies, and were found to catalyze the chemo- and stereoselective oxidation of thioanisole into the S sulfoxide, the best yield (85 ± 4%) and enantiomeric excess (40% ± 3%) being obtained with Fe(III)-meso-tetra-p-carboxyphenylporphyrin-Xln10A as catalyst in the presence of imidazole as co-catalyst. The Royal Society of Chemistry 2009.
- Ricoux, Remy,Allard, Mathieu,Dubuc, Roger,Dupont, Claude,Marechal, Jean-Didier,Mahy, Jean-Pierre
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- Porphyrin supramolecular arrays formed by weakly interacting meso-functional groups on Au(111)
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The formation of a binary porphyrinic self-assembled system between meso-tetrakis(4-carboxyphenyl) porphyrin (TCPP) and meso-tetrakis(4-dimethyl amino) porphyrin (TDAP) was easily designed through non-covalent interactions in solution and adsorbed on a gold substrate. It was found that non-covalent interactions and geometrical conformations between porphyrins allow their self-assembly into a well-defined arrangement, which was confirmed by UV-Vis spectroscopy, electrochemistry, atomic force microscopy and density functional theory (DFT) studies.
- Sánchez-Mu?oz, Esteban,Gárate-Morales, José L.,Sandoval-Lira, Jacinto,Hernández-Pérez, Julio M.,Aguilar-Sánchez, Rocío
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- Synthesis and catalytic behavior of tetrakis(4-carboxyphenyl) porphyrin-periodic mesoporous organosilica
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The periodic mesoporous organosilica having the tetrakis(4-carboxyphenyl) porphyrin (TCPP) unit was successfully synthesized by the direct co-condensation method using microwave with the corresponding tetra-silane. The tetra-silane precursor, TCPP-silsesquioxane was prepared through the reaction of TCPP with the APTES(3-Aminopropyltrietoxysilane). And TCPP-PMOs were synthesized with sodium metasilicate as a silica source and P123 (EO20PO70EO20) as a supramolecular template at 100 °C. The TCPP-PMO-n (n = 2.5 and 5.0, n refers to the molar percentage of TCPP precursor per silica) materials had >400 m2 g-1 of specific surface areas with ～8.7 nm of pore diameter. TCPP-PMOs were illustrated to give superiority in the organocatalytic hydrogen transfer reactions of various ketones such as acetophenone, cyclohexanone and pinacolone as well as good activity in the photocatalytic degradation of methylene blue (MB) without metal incorporation. Fe-TCPP-PMO prepared by ion-exchange method gave also good activity and selectivity in the oxidation of cyclohexene. The Royal Society of Chemistry 2010.
- Jeong, Eun-Young,Burri, Abhishek,Lee, Seung-Yeop,Park, Sang-Eon
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- A large π-conjugated tetrakis (4-carboxyphenyl) porphyrin anode enables high specific capacity and superior cycling stability in lithium-ion batteries
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We demonstrated a novel single molecule-tetrakis(4-carboxyphenyl) porphyrin (TCPP) with a large π-conjugated system as a high-performance organic anode of lithium batteries. It was found that this TCPP displayed relatively low solubility (-1) in a 1 M LiDFOB/PC electrolyte, high reversible specific capacity (ca. 1200 mA h g-1 at 358 mA g-1), excellent rate capability (548.4 mA h g-1 at 8 A g-1) and superior cycling performance (capacity retention of 89percent after 2500 cycles at 6 A g-1).
- Cui, Guanglei,Du, Xiaofan,Liu, Hao,Luo, Ting,Wu, Han,Xu, Hai,Yang, Jinfeng,Zhang, Jianjun,Zhang, Jinning,Zhang, Min
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- Metal-Organic Framework-Templated Porous Carbon for Highly Efficient Catalysis: The Critical Role of Pyrrolic Nitrogen Species
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Metal-free catalysts are of great importance and alternative candidates to conventional metal-based catalysts for many reactions. Herein, several types of metal-organic frameworks have been exploited as templates/precursors to afford porous carbon materials with various nitrogen dopant forms and contents, degrees of graphitization, porosities, and surface areas. Amongst these materials, the PCN-224-templated porous carbon material optimized by pyrolysis at 700°C (denoted as PCN-224-700) is composed of amorphous carbon coated with well-defined graphene layers, offering a high surface area, hierarchical pores, and high nitrogen content (mainly, pyrrolic nitrogen species). Remarkably, as a metal-free catalyst, PCN-224-700 exhibits a low activation energy and superior activity to most metallic catalysts in the catalytic reduction of 4-nitrophenol to 4-aminophenol. Theoretical investigations suggest that the content and type of the nitrogen dopant play crucial roles in determining the catalytic performance and that the pyrrolic nitrogen species makes the dominant contribution to this activity, which explains the excellent efficiency of the PCN-224-700 catalyst well.
- Huang, Gang,Yang, Li,Ma, Xiao,Jiang, Jun,Yu, Shu-Hong,Jiang, Hai-Long
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- Fabrication and application of copper metal–organic frameworks as nanocarriers for pH-responsive anticancer drug delivery
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Copper-based metal?organic frameworks (Cu-MOFs) have been extensively used in delivery of several therapeutics because of their cytocompatibility, favorable degradation and structural flexibility. In this work, we investigated two types of Cu-MOF-based nanocomposites including GO/Cu-TCPP and Fe3O4@Cu3(BTC)2 for loading of doxorubicin (DOX) and pH-sensitive release of the drug in vitro. The Fe3O4@Cu3(BTC)2 is an octahedron network structure, while the GO/Cu-TCPP nanocomposite consists of copper (II)-porphyrin metal–organic framework (Cu-TCPP) crystals embedded between exfoliated graphene oxide (GO) layers. Our studies show that GO/Cu-TCPP has adsorbed more doxorubicin (DOX) (45.7?wt.%) compared to Fe3O4@Cu3(BTC)2 (40.5?wt.%). More drug loading for Cu3(BTC)2 was also obtained than that of Cu-TCPP. For GO/Cu-TCPP at pH 5, 98.9% of DOX released for 60?h and 33.5% of DOX released after 60?h at pH 7.4, while the released amount of DOX from Fe3O4@Cu3(BTC)2 at pH 5 reached 85.5% and 33.5% at pH 7.4 afterward 60?h. The difference between the amount of drug released in two nanocomposites related to drug loading capacity demonstrating the impact nanocomposite structure on the smart MOF construction for pH-responsive behavior in vitro. Based on the results, the GO/Cu-TCPP and Fe3O4@Cu3(BTC)2 nanocomposites possess low toxicity and good biocompatibility, but DOX-loaded GO/Cu-TCPP generate better toxicity to cancer cells compared with Fe3O4@Cu3(BTC)2-DOX. Graphical abstract: [Figure not available: see fulltext.]
- Gharehdaghi, Zahra,Molaabasi, Fatemeh,Naghib, Seyed Morteza,Rahimi, Rahmatollah
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- Surface decorated magnetic nanoparticles with Mn-porphyrin as an effective catalyst for oxidation of sulfides
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Mn-porphyrin complex was anchored coordinatively to silica-coated surface of magnetic nanoparticles (SMNP). Afterward, a heterogeneous nanocatalyst (Fe3O4@SiO2-MnTCPP) has been characterized by Fourier transform infrared (FT-IR), ultraviolet-visible (UV-vis) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), and transmission electron microscope (TEM). A thermal stability up to around 350°C was verified for prepared nanocatalyst based on thermogravimetric analysis. Finally, the catalytic performance of magnetically recoverable Mn-catalyst was exploited in the green oxidation of different sulfides with urea hydrogen peroxide (UHP) in the presence of imidazole as co-catalyst in ethanol under heterogeneous conditions. The eco-friendly property of ethanol strongly induced us to employ it as the reaction solvent in this oxidation system. Complete conversion (≥99) of sulfides to the corresponding sulfoxide or sulfones was obtained for ethyl phenyl sulfide, phenyl vinyl sulfide, diallyl sulfide, thiocyanatoethane, 2-ethyl mercaptoethanol and tetrahydrothiophene. Moreover, the recovered catalysts keep constant conversion yield up to at least three cycles.
- Shokoohi, Saeedeh,Rayati, Saeed
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- A chromatography-free synthesis of meso-Tetrakis(4-formylphenyl) porphyrin and meso-Tetrakis(3-formylphenyl) porphyrin: Versatile synthons in supramolecular and macromolecular chemistry
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A facile synthetic strategy was developed for the synthesis of meso-Tetrakis(4-formyl-phenyl)porphyrin and meso-Tetrakis(3-formylphenyl)porphyrin from commercially available starting materials. This method gives facile access to practical amounts of these synthons in high purity and good overall yield, without employing laborious chromatographic separations. The reduction of the respective carboxylic acid-functionalized porphyrins by LiAlH4 afforded the tetra(benzylalcohol)porphyrin intermediates, subsequently utilized in a Parikh-Doering oxidation to selectively afford the desired tetraformylated products. The inherent ease of synthesis of these porphyrin building blocks provides a convenient pathway for the synthesis of various macromolecular and supramolecular architectures for applied chemical technologies.
- De Bruin, Bas,Mathew, Simon,Meeus, Eva J.,Mouarrawis, Valentinos,Reek, Joost
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- Porphyrin-Based Metal-Organic Framework Probe: Highly Selective and Sensitive Fluorescent Turn-On Sensor for M3+(Al3+, Cr3+, and Fe3+) Ions
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The development of porphyrin-based metal-organic frameworks (MOFs) has attracted significant interest in the scientific community in recent years because of their versatile applications particularly in optical and electronic fields. In this study, a highly selective and sensitive fluorescent turn-on sensor using a porphyrinic MOF, Tb-TCPP, is presented, which displays a 10-fold fluorescence enhancement in the presence of Al3+, Cr3+, and Fe3+ ions. The detection limit is in the nM region. For the Al3+ ion, it could be visually detected at concentrations as low as 5 mM within 15 min. Tb-TCPP could also be used as an indicator for acidic or alkaline solutions at pH values of >9 and 3. The studies on the detection mechanism illustrate that cation exchange proceed between Tb-TCPP and these M3+ ions, and consequently, energy transfer from TCPP to Tb3+ is suppressed and π*-πenergy transfer of the porphyrin ligand is significantly enhanced.
- Fu, Chenchen,Sun, Xinran,Zhang, Guoda,Shi, Pengfei,Cui, Ping
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p. 1116 - 1123
(2021/02/05)
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- Defect-engineered porphyrinic metal-organic framework nanoparticles for targeted multimodal cancer phototheranostics
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Defect-engineered porphyrinic MOF nanoparticles were fabricated with anin situone-pot protocol using cypate as the co-ligand and modulator. This multifunctional nanoplatform integrated the photothermal and multimodal imaging properties of cypate with the photodynamic effects of porphyrins, thus achieving targeted multimodal cancer phototheranostics after folic acid modification.
- Wang, Chenyuan,Xiong, Chuxiao,Li, Zhike,Hu, Liefeng,Wei, Jianshuang,Tian, Jian
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p. 4035 - 4038
(2021/04/28)
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- Porphyrin-Based Metal-Organic Frameworks for Efficient Photocatalytic H2Production under Visible-Light Irradiation
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Metal-organic frameworks (MOFs) are important photocatalytic materials for H2 production. To clarify the structure-function relationship and improve the photocatalytic activity, herein we explored a series of porphyrin-based zirconium MOFs (PCN-H2/Ptx:y, where x:y = 4:1, 3:2, 2:3, and 0:1) containing different ratios of H2TCPP and PtIITCPP [TCPP = tetrakis(4-carboxyphenyl)porphyrinate] as isostructural ligands and Zr6 clusters as nodes. Under visible-light irradiation, PCN-H2/Pt0:1 shows the highest average H2 evolution reaction rate (351.08 μmol h-1 g-1), which decreases along with lowering of the ratio of PtIITCPP in the PCN-H2/Ptx:y series. The differences in photocatalytic activity are attributed to more uniformly dispersed Pt2+ ions in PCN-H2/Pt0:1, which promotes charge transfer from porphyrins (photosensitizers) to PtII ions (catalytic centers), leading to efficient charge separation in the MOF materials. The bifunctional MOFs with photosensitizers and catalytic centers provide new insight for the design and application of porphyrin-based photocatalytic systems for visible-light-driven H2 production.
- Lin, Chenxiang,Han, Chaozheng,Zhang, Haijiao,Gong, Lei,Gao, Ying,Wang, Hailong,Bian, Yongzhong,Li, Renjie,Jiang, Jianzhuang
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p. 3988 - 3995
(2021/04/07)
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- Pd-porphyrin complex-catalyzed allylation of indole with allylic alcohols through C3–C2 coupling
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Appropriate and efficient way for the preparation of 3-allyl-2,3-dihydro-2,3′-bisindoles has been developed via homocoupling of N–H indole. Pd-porphyrin-catalyzed allylation of indoles with allylic alcohols in the presence of PBr3 and a base is developed. The reaction involves dimerization at the C3 and C2 positions of the indoles, giving 2-allylated 3-(indolin-2-yl)-1H-indoles in moderate to good yields. 3-(Indolin-2-yl)-1H-indole derivatives serve as intermediates for the synthesis of pharmaceutically active molecules.
- Atia, Alaa A.,Kimura, Masanari
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- Metalloporphyrin-Decorated Titanium Dioxide Nanosheets for Efficient Photocatalytic Carbon Dioxide Reduction
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In photocatalysis, the most efficient way to separate photogenerated electron-hole pairs has been extensively studied. However, the methods to increase the quantities of free electrons are neglected. Herein, we used a self-assembly method to fabricate MTCPP/TiO2 composite materials with a series of metalloporphyrins (MTCPPs, M = Fe, Co, Zn) as sensitizers to modify TiO2 nanosheets. First, abundant carboxyl and hydroxyl on porphyrin were adsorbed by metal ions. Then, the remaining carboxyl and hydroxyl on porphyrin were anchored on the surface of TiO2 nanosheets. Finally, MTCPP/TiO2 was obtained by a layer-by-layer self-assembly process. MTCPP broadens the light response of TiO2 from ultraviolet light to visible light and enhances the CO2 adsorption ability. Moreover, metal ions coordinating with porphyrin regulate the electron density of the porphyrin ring and provide a stronger πfeedback bond, which promote charge separation. Consequently, by optimizing the type of metal ion, the yield of ZnTCPP/TiO2 composites reached 109.33 μmol/(g h) of CO and 9.94 μmol/(g h) of CH4, which was more than 50 times that of pure TiO2. This study proposes a possible visible-light-induced CO2 reduction mechanism of metal-ion-based photocatalysis, which provides great insights into optimizing the designation of efficient photocatalysis.
- Li, Ang,Chen, Siyuan,Yang, Fucheng,Gao, Hongyi,Dong, Cheng,Wang, Ge
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p. 18337 - 18346
(2021/11/23)
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- Photodynamic therapy agent for relieving tumor hypoxia as well as preparation method and application thereof
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The invention discloses a photodynamic therapy agent for relieving tumor hypoxia as well as a preparation method and application thereof, and belongs to the technical field of medicines. The photodynamic therapy agent is a metal-organic framework nano composite material loaded with O2. The metal-organic framework nano composite material is metal-organic framework nano particles Zr-TCPP (Fe), the interiors of nano frameworks of the nano particles Zr-TCPP (Fe) are modified with perfluorooctanoic acid, and meanwhile glucose oxidase GOx is further adsorbed in pore channels of the nano particles Zr-TCPP (Fe). According to the invention, a drug delivery system capable of catalyzing tumor to endogenously generate O2 is designed while O2 is delivered to tumor tissue, so that the hypoxic environment can be remarkably improved, and the photodynamic therapy effect is enhanced. In addition, the synthetic steps of the therapy agent are relatively simple, and the yield is relatively high; and a synthetic method is simple and relatively low in cost, so that the method is suitable for large-scale production.
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Paragraph 0053-0054
(2021/01/28)
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- Manganese porphyrin-based metal-organic framework for synergistic sonodynamic therapy and ferroptosis in hypoxic tumors
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Development of efficient therapeutic strategy to incorporate ultrasound (US)-triggered sonodynamic therapy (SDT) and ferroptosis is highly promising in cancer therapy. However, the SDT efficacy is severely limited by the hypoxia and high glutathione (GSH) in the tumor microenvironment, and ferroptosis is highly associated with reactive oxygen species (ROS) and GSH depletion. Methods: A manganese porphyrin-based metal-organic framework (Mn-MOF) was constructed as a nanosensitizer to self-supply oxygen (O2) and decrease GSH for enhanced SDT and ferroptosis. In vitro and in vivo analysis, including characterization, O2 generation, GSH depletion, ROS generation, lipid peroxidation, antitumor efficacy and tumor immune microenvironment were systematically evaluated. Results: Mn-MOF exhibited catalase-like and GSH decreasing activity in vitro. After efficient internalization into cancer cells, Mn-MOF persistently catalyzed tumor-overexpressed H2O2 to in-situ produce O2 to relieve tumor hypoxia and decrease GSH and GPX4, which facilitated the formation of ROS and ferroptosis to kill cancer cells upon US irradiation in hypoxic tumors. Thus, strong anticancer and anti-metastatic activity was found in H22 and 4T1 tumor-bearing mice after a single administration of Mn-MOF upon a single US irradiation. In addition, Mn-MOF showed strong antitumor immunity and improved immunosuppressive microenvironment upon US irradiation by increasing the numbers of activated CD8+ T cells and matured dendritic cells and decreaing the numbers of myeloid-derived suppressor cells in tumor tissues. Conclusions: Mn-MOF holds great potential for hypoxic cancer therapy.
- Xu, Qingbo,Zhan, Guiting,Zhang, Zelong,Yong, Tuying,Yang, Xiangliang,Gan, Lu
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p. 1937 - 1952
(2021/01/06)
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- Efficient and selective oxidation of 5-hydroxymethylfurfural catalyzed by metal porphyrin supported by alkaline lignin: Solvent optimization and catalyst loading
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Cobalt (II)-meso-tetra(4-carboxyphenyl) porphyrin supported by deprotected lignin was synthesized through the covalent linkage between carboxy groups in the porphyrin and hydroxyl groups in the lignin. The resulting supporting catalysts were applied in the selective oxidation of 5-hydroxymethylfurfural. Through solvent optimization, 5-hydroxymethyl-2-furancarboxylic acid and 2,5-furandicarboxylic acid could be selectively obtained. Steric effect of lignin prevented unwanted aggregation-caused quenching, avoiding catalyst deactivation. Thus, supported catalysts displayed better catalytic efficiency compared free metal porphyrin catalyst. Unlike the excessive use of sodium hydroxide in the oxidation of HMF catalyzed by metal catalysts, an equivalent amount of sodium hydroxide was used in this oxidation process. Meanwhile, lower activation energy was detected when metal porphyrin supported by deprotected lignin was used. By adjusting the pH in the reaction, supported catalysts could be reused. The catalytic activity remained stable during the recycling experiments.
- Fang, Zheng,Guo, Kai,He, Wei,Wu, Hao,Yang, Xiaobing,Zhu, Yuchen
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- Investigation of antimony adsorption on a zirconium-porphyrin-based metal-organic framework
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A zirconium-porphyrin based organic framework PCN-222 was employed for investigating the adsorption performance of Sb(iii) in aqueous solution. It is proved that the adsorbent has the advantages of rapid adsorption and high capacity. Interestingly, we discover that PCN-222 shows pH-dependent adsorption performance, with higher capacity at pH = 2 and 8 than at pH = 5. According to XPS and FT-IR analyses, an adsorption model of PCN-222 with pH = 2, 5, and 8 is proposed, that is, zirconium clusters combine with antimony at different pH values with bidentate complexes, monodentate complexes, and alkaline monodentate complexes, thus producing an excellent adsorption effect. Moreover, the porphyrin ring is also beneficial for the adsorption of antimony. In addition, PCN-222 shows good regeneration and recycling performance, and it is a promising adsorbent as well as a platform for investigating the removal of Sb(iii) in water treatment.
- Guo, Rongxiu,Guo, Ying,Jia, Hongna,Li, Hong,Niu, Dun,Sun, Hong-Bin,Sun, Zejun,Wang, Yao,Xie, Nianyi,Zhang, Xinyue
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p. 13932 - 13942
(2021/10/19)
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- Magnetically recoverable porphyrin-based nanocatalysts for the effective oxidation of olefins with hydrogen peroxide: A comparative study
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In this paper, preparation, characterization and catalytic applications of metalloporphyrin-based magnetic nanocatalysts were investigated. meso-Tetrakis(4-carboxyphenyl)porphyrinatoiron(iii) chloride (Fe(TCPP)Cl) and meso-tetrakis(4-carboxyphenyl)porphyrinatomanganese(iii) acetate (Mn(TCPP)OAc) were separately immobilized onto the surface of amine functionalized magnetic nanoparticles (Fe3O4/SiO2/NH2) via covalent attachment. The obtained nanocatalysts were characterized using FT-IR and UV-Vis and atomic absorption spectroscopy, X-ray powder diffraction (XRD), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM). The catalytic efficiency of Fe3O4/SiO2/NH2-Fe(TCPP)Cl and Fe3O4/SiO2/NH2-Mn(TCPP)OAc for the green oxidation of alkenes with H2O2 was investigated in a comparative manner. The Mn-porphyrin based magnetic nanocatalyst shows higher catalytic efficiency compared to the Fe-porphyrin. In addition, the prepared magnetic nanocatalyst exhibited excellent reusability and could be reused at least five times without significant leaching or loss of activity. This journal is
- Rayati, Saeed,Moradi, Dana,Nejabat, Fatemeh
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supporting information
p. 19385 - 19392
(2020/11/23)
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- Docking studies, antitumor and antioxidant evaluation of newly synthesized porphyrin and metalloporphyrin derivatives
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In this work, we have synthesized a series of novel porphyrin derivatives, 1–5, in high yields. The metal complexes of two of the newly synthesized porphyrin derivatives, 1a–d and 2a–d, have also been synthesized in high yields and characterized. In the synthesis of the new porphyrins and metalloporphrins, we employed our reported strategy in which we utilized N,N-dimethylformamide (DMF) as a capping agent in the reaction of pyrrole with different hetero-aryl aldehydes. The new porphyrin derivatives are equipped with different aromatic substituents and hetero-cycles at the peripheral position. The structures of the new compounds were confirmed by elemental and spectral analyses. The geometry and magnetic properties of the new metalloporphyrins 1a–d and 2a–d have also been studied. Antioxidant and cytotoxic activities of the new compounds were evaluated and structure-activity relationships were performed. Porphyrin derivatives 2a and 4 showed exceptional antioxidant activity compared to ascorbic acid as a reference. While the derivatives 2, 3, and 5 exhibited very strong cytotoxic activity against two human cell lines, HePG-2 and MCF-7. Docking for the most promising antioxidant porphyrins, 2a and 4, into the binding active site of antioxidant protein Human Peroxiredoxin (code: 1HD2) has been carried out to detect the degree of recognition antioxidant activity. Molecular docking of the most cytotoxic active porphyrins, 3 and 5, into the biding site of telomerase inhibitor enzyme has been carried out to assess the degree of recognition cytotoxic activity.
- Abou-Zeid, Laila,Ahmed, Asmaa,El-Asmy, Hala A.,Fadda, Ahmed A.,Omar, Walaa A. E.
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- Comparative in vitro Studies of the Topoisomerase I Inhibition and Anticancer Activities of Metallated N-Confused Porphyrins and Metallated Porphyrins
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Using the original approach, a series of metallated N-confused porphyrins and metallated porphyrins have been synthesized and characterized. For all the synthesized porphyrins, in vitro studies of cytotoxic activity against K562, U937, HL-60, Jurkat, A549 and HeLa cancer cell lines, the ability to induce apoptosis and effects on the cell cycle as well as the kinetics of proliferative activity of porphyrins and their respective metallated complexes in real time have been developed. The inhibitory activity of metallated porphyrins against human topoisomerase I and the possible mechanism of inhibition have been carried out by modelling using molecular docking.
- D'yakonov, Vladimir A.,Dzhemilev, Usein M.,Dzhemileva, Lilya U.,Halder, Nyancy,Ramazanov, Ilfir R.,Rath, Harapriya
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- The cocatalyst roles of three anionic Cd(II) porphyrinic metal-organic frameworks in the photocatalytic CO2 reduction to CO process carried out in Ru(bpy)3Cl2/CH3CN/H2O/Triethylamine or triethanolamine system
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Three 3D, anionic Cd(II) porphyrinic metal-organic frameworks (PMOFs), 1(3.5:1)-2d-120 ([Cd3·2(H2TCPP)2][(CH3)2NH2]1.6), its Li+-exchanged product (e.g. Li+-1-120, formula: [Cd3·2(H2TCPP)2]Li1.6) and 1(10:1)-4d-120 ([Cd3·7H2TCPP)2][(CH3)2NH2]0.6) were synthesized, all of which have the same PXRD pattern. Their VB and CB band-edge positions were determined in nonaqueous electrolyte as ?0.59, 1.12; ?0.60, 1.11; and ?0.60, 1.16, respectively. Their light absorption properties in the range of 250–2500 ?nm were obtained by UV–Vis-IR reflectance spectroscopy. Transient photocurrent responses, electrochemical impedance spectra (EIS) and solid state photoluminescence (PL) spectra of the three PMOFs were obtained. When irradiated using light of 430 ?nm and ?0.5-0.5 bias potentials (versus Ag/Ag+ electrode in CH3CN), both positive and negative photocurrent were observed. Mott-Schottky plot measurements indicate that they are intrinsic semiconductors. Although these three PMOFs can photocatalytically reduce CO2 to CO in the absence of Ru (bpy)3Cl2, their catalytic abilities are very weak. The roles of these PMOFs in CH3CN/trimethylamine (TEA) or triethanolamine (TEOA)/H2O (400 ?μL)/Ru (bpy)3Cl2.6H2O was found to be mainly cocatalysts, and Ru (bpy)3Cl2 was the actual photocatalyst in the presence of small amounts of water (0–400 ?μL). These PMOFs act as cocatalysts due to the increased reducing power upon light irradiation. Reducing the charge of the framework can reduce the efficiencies of the photocatalytic CO2 reduction to CO. Li+-1-120 was found to be able to react with Ru (bpy)3Cl2 when sufficient amounts of H2O are present in CH3CN and TEA system, preventing the photocatalytic property of Ru (bpy)3Cl2 to be released. In addition, we found that TEOA is a worse reducing agent than TEA, leading to much lower photocatalytic efficiency of the system. Mechanisms were proposed for reactions occurred in CH3CN/TEA (or TEOA)/H2O (400 ?μL)/Ru (bpy)3Cl2.6H2O/PMOF system, and strategies to improve the photocatalytic performance of CO2 reduction to CO were proposed.
- Bao, Jianchun,Ding, Jie,Fang, Min,Feng, Yuying,Jia, Shuyu,Li, Ke,Wu, Yong,Wu, Yusheng
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- Rhodium porphyrin molecule-based catalysts for the hydrogenation of biomass derived levulinic acid to biofuel additive γ-valerolactone
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Rhodium-meso-tetraphenylporphyrin (RhTPP) and rhodium-meso-tetrakis(4-carboxyphenyl)porphyrin (RhTCPP) complexes were synthesized and surface grafted on amine-functional mesoporous molecular sieves. The formation of ligands (TPP and TCPP) and their rhodium complexes (RhTPP and RhTCPP) was evident with the help of 1H NMR, 13C NMR, mass spectral and elemental (CHN) analysis. The absence of the pyrrole proton of the porphyrin units on RhTPP and RhTCPP confirmed the successful formation of metallo-macro-molecules. Further, RhTPP and RhTCPP were fixed on the surface of SBA-15 through amino-silane as the linker. The rhodium containing homogeneous (RhTPP and RhTCPP) and heterogeneous catalysts (RhTPP-SBA-AM and RhTCPP-SBA-AM) were used for biomass-derived levulinic acid hydrogenation. Further, the synthesized catalysts were utilized for the hydrogenation of various organic molecules having arene, carbonyl, and alkene functionality under moderate reaction conditions. Both homogeneous and heterogeneous catalysts showed more than 95% levulinic acid conversion even after four cycles. The homogeneous RhTPP and RhTCPP yielded γ-valerolactone (GVL) as a major product, whereas heterogeneous catalysts showed only comparable γ-valerolactone (GVL) selectivity, with improved reusability and recylability in the presence of relatively lower amounts of rhodium complexes. Among RhTPP and RhTCPP, RhTPP showed better selectivity for γ-valerolactone (GVL) compared to RhTCPP. Further, as the number of catalytic runs increased, there was a gradual increase in diol selectivity, which was predominant in the case of RhTCPP, possibly due to the presence of the hydrophilic carboxylate ion which facilitates the interaction of water by-products with γ-valerolactone and favours diol formation. The hydrophobic environment of the RhTPP catalyst facilitated the formation of γ-valerolactone as the major product even in the fifth run. This journal is
- Anjali, Kaiprathu,Christopher, Jayaraj,Sakthivel, Ayyamperumal,Venkatesha, Naragalu J.
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p. 11064 - 11075
(2020/07/15)
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- Copper based macromolecular catalysts for the hydroxylation of phenols
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Copper containing macromolecules, viz., Copper-meso-tetrakis-(4-carboxyphenyl)porphyrin (CuTCPP) and Copper-meso-tetra-phenylporphyrin (CuTPP) complexes were synthesized and heterogenized on the surface of aminated SBA-15 molecular sieves. The 1H NMR, mass spectral and elemental (CHN) analyses were performed to confirm the formation of these copper complexes (CuTCPP and CuTPP). The absence of 1H NMR signal, characteristic of N[sbnd]H bond (-2.79 ppm in TCPP and -2.74 ppm in TPP) in CuTCPP and CuTPP clearly confirms the incorporation of copper ion in to the cavities of the TCPP and TPP ligands. In addition, the decreased intensity of the soret band and the reduction of the number of Q bands also supports the formation of copper complexes. Further the homogeneous CuTCPP and CuTPP were grafted on the amino functionalized SBA-15. The grafting of copper complexes on amino functionalised SBA-15 was evident from the surface area analysis, powder XRD and N2 sorption isotherm. In the powder XRD, the shift in 2θ value compared to parent SBA-15 materials, and the broadening of the signal supports the grafting of copper complexes in to the amino functionalized SBA-15. Both homogeneous and heterogeneous copper macromolecular complexes were used as catalysts for the hydroxylation of phenolic compounds. The catalysts showed comparable conversion (72%) with the formation of ortho- and para- substituted products which have industrial importance. The hydroxylation reaction using the copper based macromolecular catalyst was found to be first order with an activation energy of 26.03 KJ/mol. Subsequently various substituted phenolic compounds, anisole and benzene also yielded the corresponding hydroxylated product with comparable conversion.
- Anjali, Kaiprathu,Ganesh, Venkatachalam,Christopher, Jayaraj,Sakthivel, Ayyamperumal
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- Selective Solvent-Free and Additive-Free Oxidation of Primary Benzylic C–H Bonds with O2 Catalyzed by the Combination of Metalloporphyrin with N-Hydroxyphthalimide
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Abstract: A protocol for solvent-free and additive-free oxidation of primary benzylic C–H bonds with O2 was presented through adjusting the combination of metalloporphyrins and NHPI as binary catalysts to overcome the deficiencies encountered in current oxidation systems. The effects of reaction temperature, porphyrin structure, central metal, catalyst loading and O2 pressure were investigated systematically. For the optimized combination of T(2-OCH3)PPCo and NHPI, all the primary benzylic C–H bonds could be functionalized efficiently and selectively at 120 °C and 1.0?MPa O2 with aromatic acids as the primary products. The selectivity towards aromatic acids could reach up to 70–95% in the conversion of more than 30% for most of the substrates possessing primary benzylic C–H bonds in the metalloporphyrin loading of 0.012% (mol/mol). And the superior performance of T(2-OCH3)PPCo among the metalloporphyrins investigated was mainly attributed to its high efficiency in charge transfer and fewer positive charges around central metal Co (II) which favored the adduction of O2 to cobalt (II) forming the high-valence metal-oxo complex followed by the production of phthalimide N-oxyl radical (PINO) and the initiation of the catalytic oxidation cycle. This work would provide not only an efficient protocol in utilization of hydrocarbons containing primary benzylic C–H bonds, but also a significant reference in the construction of more efficient C–H bonds oxidation systems. Graphic Abstract: The solvent-free and additive-free oxidation of primary benzylic C–H bonds with O2 was presented through adjusting the combination of metalloporphyrins and NHPI as binary catalysts, and the highest selectivity towards aromatic acid reached up to 95.1% with the conversion of 88.5% in the optimized combination of T(2-OCH3)PPCo and NHPI.[Figure not available: see fulltext.].
- Shen, Hai-Min,Qi, Bei,Hu, Meng-Yun,Liu, Lei,Ye, Hong-Liang,She, Yuan-Bin
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p. 3096 - 3111
(2020/04/29)
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- Freestanding Millimeter-Scale Porphyrin-Based Monoatomic Layers with 0.28 nm Thickness for CO2 Electrocatalysis
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Developing two-dimensional (2D) and single atomic layered materials is a fascinating challenge. Here we successfully synthesize porphyrin-based monoatomic layer (PML), a freestanding 2D porphyrin-based material of monomer-unit thickness (2.8 ?). The solvothermal method provides a bottom-up approach for tailoring the monoatomic layer from the nanoscale to the milliscale. PMLs containing accurately tailorable M-N4 units (M=Cu and Au) were synthesized, which present metal center-dependent performance for CO2 electrocatalysis. PML with Cu-N4 centers performs high faradaic efficiencies of HCOO? and CH4 (80.86 % and 11.51 % at ?0.7 V, respectively) while PML with Au-N4 centers generates HCOO? and CO as major products (40.90 % and 34.40 % at ?0.8 V, respectively). Irreversible restructuring behavior of Cu sites is also observed. Based on the graphene-like properties and metal center-selectivity relationships, we believe that PML will play a distinct role in various applications.
- Wang, Xun,Yang, Deren,Yang, Haozhou,Zhou, Yue,Zuo, Shouwei
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p. 18954 - 18959
(2020/09/01)
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- Boosting Interfacial Charge-Transfer Kinetics for Efficient Overall CO2Photoreduction via Rational Design of Coordination Spheres on Metal-Organic Frameworks
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The recombination of electron-hole pairs severely detracts from the efficiency of photocatalysts. This issue could be addressed in metal-organic frameworks (MOFs) through optimization of the charge-transfer kinetics via rational design of structures at atomic level. Herein, a pyrazolyl porphyrinic Ni-MOF (PCN-601), integrating light harvesters, active catalytic sites, and high surface areas, has been demonstrated as a superior and durable photocatalyst for visible-light-driven overall CO2 reduction with H2O vapor at room temperature. Kinetic studies reveal that the robust coordination spheres of pyrazolyl groups and Ni-oxo clusters endow PCN-601 with proper energy band alignment and ultrafast ligand-to-node electron transfer. Consequently, the CO2-to-CH4 production rate of PCN-601 far exceeds those of the analogous MOFs based on carboxylate porphyrin and the classic Pt/CdS photocatalyst by more than 3- and 20-fold, respectively. The reaction avoids the use of hole scavengers and proceeds in a gaseous phase which can take full advantage of the high gas uptake of MOFs. This work demonstrates that the rational design of coordination spheres in MOF structures not only reconciles the contradiction between reactivity and stability but also greatly promotes the interfacial charge transfer to achieve optimized kinetics, providing guidance for the design of highly efficient MOF photocatalysts.
- Cao, Rong,Fang, Zhi-Bin,Gong, Xue-Qing,Jin, Shengye,Liu, Junxue,Liu, Tian-Fu,Liu, Ting-Ting,Wang, Kecheng,Wu, Xin-Ping,Yin, Qi,Zhou, Hong-Cai
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p. 12515 - 12523
(2020/08/07)
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- Titanium Metal-Organic Framework Single Crystal
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A titanium metal-organic framework (Ti MOF) single crystal according to the present invention includes a titanium-oxo structural unit, wherein a tetravalent organic ligand that absorbs visible light is bound to titanium of the titanium-oxo structural unit, and four functional groups of the tetravalent organic ligand are bound to different titanium, separately. The Ti MOF single crystal according to the present invention has low band gap energy, excellent microporosity and high specific surface area.COPYRIGHT KIPO 2020
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Paragraph 0111-0112
(2020/07/11)
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- Multi-component supramolecular gels induce protonation of a porphyrin exciplex to achieve improved collective optical properties for effective photocatalytic hydrogen generation
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Towards mimicking natural photosystems, supramolecular gels containing two types of porphyrins were developed for photocatalysis. Protonation and J-aggregation of porphyrins within gels expand the absorption to a wide range of visible wavelengths. Porphyrin exciplex formation renders a smaller bandgap for photo-induced electron generation. These features induce effective photocatalytic hydrogen generation.
- Feng, Xuenan,Jiang, Jianzhuang,Lin, Chenxiang,Wang, Tianyu,Yang, Gengxiang
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supporting information
p. 527 - 530
(2020/01/29)
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- Structural tuning of zinc-porphyrin frameworks: Via auxiliary nitrogen-containing ligands towards selective adsorption of cationic dyes
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Three metal-organic frameworks have been synthesized by using N-containing ligands and meso-tetra(4-carboxyphenyl)porphyrin, which all exhibit distinct selective adsorption capacities toward various organic dyes, illustrating the most important influence of the structural tuning.
- Wang, Xiao-Ning,Li, Jiang-Li,Zhao, Yu-Meng,Pang, Jiandong,Li, Bao,Zhang, Tian-Le,Zhou, Hong-Cai
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supporting information
p. 6527 - 6530
(2019/06/13)
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- Iridium Tetra(4-carboxyphenyl) Porphyrin, Calix[4]pyrrole and Tetraphenyl Porphyrin Complexes as Potential Hydrogenation Catalysts
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Here we report the preparation of first examples of iridium-based organometallic macromolecules, viz., iridium-tetra (4-carboxyphenyl)porphyrin (IrTCPP), iridium-calix[4]pyrrole (IrCP) iridium-tetraphenylporphyrin (IrTPP), which are effective catalysts for hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) and 1,4-pentanediol under base free conditions. The turnover number in the range of 1220–2850 is evident for the chosen reaction using iridium macromolecule based catalysts. The heterogenization of homogeneous IrTCPP, IrCP, and IrTPP result in stable reactivity of the catalysts for several runs.
- Anjali, Kaiprathu,Aswini, Manammuzhangiyil Sivadasan,Aswin, Peringayi,Ganesh, Venkatachalam,Sakthivel, Ayyamperumal
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supporting information
p. 4087 - 4094
(2019/11/02)
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- Structural Transformation in Metal–Organic Frameworks for Reversible Binding of Oxygen
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Polycyclic aromatic derivatives can trap 1O2 to form endoperoxides (EPOs) for O2 storage and as sources of reactive oxygen species. However, these materials suffer from structural amorphism, which limit both practical applications and fundamental studies on their structural optimization for O2 capture and release. Metal–organic frameworks (MOFs) offer advantages in O2 binding, such as clear structure–performance relationships and precise controllability. Herein, we report the reversible binding of O2 is realized via the chemical transformation between anthracene-based and the corresponding EPO-based MOF. It is shown that anthracene-based MOF, the framework featuring linkers with polycyclic aromatic structure, can rapidly trap 1O2 to form EPOs and can be restored upon UV irradiation or heating to release O2. Furthermore, we confirm that photosensitizer-incorporated anthracene-based MOF are promising candidates for reversible O2 carriers controlled by switching Vis/UV irradiation.
- Zeng, Jin-Yue,Wang, Xiao-Shuang,Qi, Yong-Dan,Yu, Yun,Zeng, Xuan,Zhang, Xian-Zheng
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p. 5692 - 5696
(2019/03/27)
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- Single-Atom catalysts templated by metal-organic frameworks for electrochemical nitrogen reduction
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The electrocatalytic nitrogen reduction reaction (NRR) has much prospect for substituting the energy-consuming Haber-Bosch process. Nevertheless, its sluggish reaction kinetics and the competing hydrogen evolution reaction always result in limited ammonia yield and low faradaic efficiency (FE). In this work, an Fe-decorated porphyrinic metal-organic framework (MOF) is employed as a precursor to construct single-Atom Fe implanted nitrogen-doped carbon catalysts (Fe1-N-C) through a mixed ligand strategy. Benefiting from the highly dispersed single-Atom Fe sites, hierarchically porous structure and good conductivity, Fe1-N-C shows a FE of 4.51% and an ammonia yield rate of 1.56 × 10-11 mol cm-2 s-1 at-0.05 V versus the reversible hydrogen electrode, superior to those of Co1-N-C and Ni1-N-C. Theoretical calculations reveal that Fe1-N-C shows the lowest energy barrier of the rate-determining step during the NRR process, consistent with its highest activity obtained in experiments. This work reveals the unique potential of single-Atom catalysts for the electrochemical NRR and provides in-depth insights into the catalytic mechanism of the NRR.
- Zhang, Rui,Jiao, Long,Yang, Weijie,Wan, Gang,Jiang, Hai-Long
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p. 26371 - 26377
(2019/12/04)
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- Biomimetic Cleavage of Aryl–Nitrogen Bonds in N-Arylazoles Catalyzed by Metalloporphyrins
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The cleavage of C–N single bonds of N-containing compounds provides either an excellent nitrogen source or an excellent carbon source. In this study, an efficient metalloporphyrins/H2O2 cleavage of C–N bonds of arylpyrazoles was investigated. The effects of different factors, including different catalysts, catalyst dosages, H2O2 dosages, reaction temperature and reaction time were studied. The experimental results showed that the optimal catalyst was FeTPPCl, and the yield of pyrazole derivatives could reach up to 12.3%, which was fourfold higher than hemin catalyzed reaction and closed to ceric ammonium nitrate catalyzed reaction, respectively. Compared with transition-metal-catalyzed and strong-oxidization cleavage of C–N bonds, this protocol is characterized by environmentally-friendly, stable, mild reaction conditions and simplified operation procedures. Graphical Abstract: [Figure not available: see fulltext.].
- Yu, Zongjiang,Zhai, Guoqing,Xian, Mo,Lu, Ming,Wang, Pengcheng,Jiang, Tao,Xu, Chao,Sun, Weizhi
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p. 2636 - 2642
(2018/06/20)
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- Titanium-Carboxylate Metal-Organic Framework Based on an Unprecedented Ti-Oxo Chain Cluster
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Titanium(IV)-based metal-organic frameworks (Ti-MOFs) have received significant attention in recent years due to their numerous photocatalytic applications. We herein prepare the single-crystalline Ti-carboxylate MOF (DGIST-1) composed of an unprecedented Ti-oxo chain cluster and the porphyrinic ligand, TCPP (tetrakis(4-carboxyphenyl)porphyrin). Preformed Ti-oxo clusters were used as Ti4+ sources to avoid the spontaneous hydrolysis and condensation reactions of traditional Ti-alkoxide precursors, thus, enabling the formation of the highly crystalline Ti-MOF. The successfully activated DGIST-1 exhibited a higher surface area (i.e., 1957.3 m2 g?1) than previously reported Ti-MOFs due to its high crystallinity. Furthermore, the visible-light-responsive photocatalytic activity of DGIST-1 was confirmed by the simultaneous generation of singlet oxygen (1O2) and superoxide (.O2?) species, in addition to the highly efficient and selective oxidation of benzyl alcohol to benzaldehyde.
- Keum, Yesub,Park, Seonghun,Chen, Ying-Pin,Park, Jinhee
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supporting information
p. 14852 - 14856
(2018/10/20)
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