T:Toxic;
106-51-4Relevant articles and documents
Effect of calcination temperature on the structure and catalytic performance of copper-ceria mixed oxide catalysts in phenol hydroxylation
Amadine, Othmane,Essamlali, Younes,Fihri, Aziz,Larzek, Mohamed,Zahouily, Mohamed
, p. 12586 - 12597 (2017)
We report on highly active CuO@CeO2 catalysts prepared by the surfactant-template method and calcined at different temperatures. Then the obtained catalysts were characterized by means of various analytical techniques. Our findings show that the BET surface area and pore volume of the CuO@CeO2 catalyst measured by N2 adsorption-desorption are decreasing with the elevation of calcination temperature. From the results of XRD and XPS, we determined the oxidation state of copper in the copper-ceria mixed oxide catalysts. The CuO@CeO2 catalysts displayed good catalytic activity for the phenol hydroxylation using H2O2 as an oxidant. Moreover, we found that the catalytic activity is improved for high calcining temperature and the optimum conditions were obtained when the catalyst CuO@CeO2 is calcined at 800 °C, which lead to higher phenol conversion of 54.62% with 92.87% of selectivity for catechol and hydroquinone. More importantly, the catalyst seems to be easily recovered by simple centrifugation. The results of catalyst recycling illustrated that the catalytic activity remained high even after five cycles with slight Cu leaching and slight loss of activity. Finally, a possible mechanism in phenol hydroxylation by H2O2 over CuO@CeO2 catalyst was also proposed.
Oxidation of Electron-Rich Arenes Using HFIP-UHP System
Llopis, Natalia,Baeza, Alejandro
, p. 6159 - 6164 (2020)
The straightforward oxidation of electron-rich arenes, namely, phenols, naphthols, and anisole derivatives, under mild reaction conditions, is described by means of the use of an environmentally benign HFIP-UHP system. The corresponding quinones or hydroxylated arenes were obtained in moderate to good yields.
Improving removal of 4-chlorophenol using a TiO2 photocatalytic system with microwave and ultraviolet radiation
Ki, Seo Jin,Jeon, Ki-Joon,Park, Young-Kwon,Jeong, Sangmin,Lee, Heon,Jung, Sang-Chul
, p. 15 - 22 (2017)
A conventional photocatalytic system is a viable tool to purify wastewaters, whereas poor degradation performance due to diverse pollutants under various conditions still leaves it behind commercial markets. This study aimed to determine the degradation e
Cocivera et al.
, p. 6598,6599 , 6601 ,6602 (1972)
The photochemistry of 4-chlorophenol in water revisited: The effect of cyclodextrins on cation and carbene reactions
Manet, Ilse,Monti, Sandra,Bortolus, Pietro,Fagnoni, Maurizio,Albini, Angelo
, p. 4274 - 4282 (2005)
The photochemistry of 4-chlorophenol (1) in water and in the presence of cyclodextrins has been studied by means of steady-state and time-resolved experiments. These have shown that 1 undergoes photoheterolysis of the C-Cl bond in the triplet state to yield the 4-hydroxyphenyl cation 32 in equilibrium with 4-oxocyclohexa-2,5-dienylidene, 33. These triplet intermediates scarcely react with a n nucleophile, such as water, nor abstract hydrogen from this solvent, thus they are long-lived (≈1 μs). Specific trapping of both intermediates has been achieved. The cation adds to 2-propenol, kadd～1.3× 108 M-1 s-1, to form the long-lived phenonium ion 11 (with λmax = 290 nm), which then converts to 3-(4-hydroxyphenyl)propane-1,2-diol (10). Carbene 33 is trapped by oxygen to give benzoquinone and is reduced by D-glucose (kq = 8.5 × 10-1 s-1) to give the phenoxyl radical (8) and phenol (9). Cyclodextrins have been found to trap the intermediates much more efficiently (kq = 9.4×10 8M-1s-1 with β-CD), which indicates that inclusion is involved. Ground state 1 forms inclusion complexes with 1:1 stoichiometry and association constants of 140 and 300 M-1 with α- and β-CD, respectively. Complexation does not change the efficiency or the mode of photofragmentation of 1; however, it does influence the course of the reaction because the major portion of the intermediates are reduced to phenol within the cavity (k′red ≥ 5 × 107 s-1) either via a radical 8 or via a radical cation 9+. Under these conditions, neither 2-propenol nor oxygen trap the intermediates to a significant extent.
Effective photodegradation of organic pollutantsin the presence of mono and bi-metallic complexes under visible-light irradiation
Chetti, Prabhakar,Gade, Ramesh,Guguloth, Venkanna,Pola, Someshwar,Ravulapelly, Koteshwar Rao,Subburu, Mahesh
, (2021)
The synthesis of new mono and bi-metallic complexes such as Zn (II) and Ag-Zn (II) complexes with organic functional group-based ligand (OFL) presented in the current work along with the exploration of their applicability in the photocatalytic degradation
Two-Dimensional Layered Zinc Silicate Nanosheets with Excellent Photocatalytic Performance for Organic Pollutant Degradation and CO2 Conversion
Wang, Lan,Bahnemann, Detlef W.,Bian, Liang,Dong, Guohui,Zhao, Jie,Wang, Chuanyi
, p. 8103 - 8108 (2019)
Two-dimensional (2D) photocatalysts are highly attractive for their great potential in environmental remediation and energy conversion. Herein, we report a novel layered zinc silicate (LZS) photocatalyst synthesized by a liquid-phase epitaxial growth route using silica derived from vermiculite, a layered silicate clay mineral, as both the lattice-matched substrate and Si source. The epitaxial growth of LZS is limited in the 2D directions, thus generating the vermiculite-type crystal structure and ultrathin nanosheet morphology with thicknesses of 8–15 nm and a lateral size of about 200 nm. Experimental observations and DFT calculations indicated that LZS has a superior band alignment for the degradation of organic pollutants and reduction of CO2 to CO. The material exhibited efficient photocatalytic performance for 4-chlorophenol (4-CP) degradation and CO2 conversion into CO and is the first example of a claylike 2D photocatalyst with strong photooxidation and photoreduction capabilities.
Electron Attachment to p-Benzoquinone and Photodetachment from Benzoquinone Anion in Nonpolar Solvents
Holroyd, R. A.
, p. 3541 - 3547 (1982)
Although p-benzoquinone has a high electron affinity (1.9 eV), its reaction with excess electrons exhibits an unusual solvent and temperature dependence.The reaction is fast and has a positive activation energy in n-pentane but is much slower and has a negative activation energy in Si(CH3)4, neopentane, and 2,2,4,4-tetramethylpentane.The results can be explained in terms of an equilibrium with a short-lived excited state of the anion: e- + benzoquinine benzoquinone(-)*.The attachment rate is fast in all solvents.The reverse, autodetachment from the excited anion, is characterized by an activation energy, which depends on the value of V0, the energy level of the electron in the liquid.For Si(CH3)4 for which V0 is the lowest (-0.55 eV), the activation energy is 5.7 kcal/mol.As V0 increases, the activation energy increases and is 9.4 kcal/mol in 2,2,4,4-tetramethylpentane for which V0=-0.35 eV.When V0 is close to zero, as in n-pentane, the activation energy is so large that detachment from the excited anion state is too slow to compete with deactivation and a fast diffusion-controlled forward rate is observed.The spectrum of benzoquinone anion as observed by the laser photodetachment technique is reported, and the threshold for photodetachment is found to be 2.32 eV in Si(CH3)4 and 2.58 eV in 2,2,4-trimethylpentane.The quantum yield of photodetachment reaches a maximum value at 480 nm in Si(CH3)4.
Kinetics and mechanism of oxidation of hydroquinone by tetrabutylammonium tribromide ion in aqueous acetic acid
Zende,Kalantre,Gokavi
, p. 1178 - 1186 (2010)
The oxidation of hydroquinone by environmentally benign tetrabutyl ammonium tribromide (TBATB) was carried out in 50% V/V aqueous acetic acid medium under pseudo-first-order conditions, keeping a large excess of hydroquinone over the oxidant. The main rea
Oxidative degradation of phenol by corona dielectric barrier discharge at gas-liquid interphase
Wang, Lei,Yu, Xin,Li, Guoxin,Li, Dailin
, p. 853 - 859 (2014)
In this study, corona gas-liquid dielectric barrier discharge reactor for phenol degradation was investigated. The discharge was formed between two needle metal electrodes and an aqueous solution surface where the counter electrode was submerged and separated by a quartz dielectric tube. Effects of solution conductivity, pH and gas composition on the degradation were examined. Experimental results showed that the degradation of phenol proceeded perfectly in a wide range of solution conductivity. In the process of degradation of phenol, ozone was additionally formed. The removal of phenol increased with the order: argon air oxygen. Increasing pH was favorable for phenol removal. When using argon as the discharge gas, the major degradation products were catechol, hydroquinone, hydroxyhydroquinone, acetic acid, formic acid and oxalic acid. In oxygen or air discharges, 1,4-benzoquinone and muconic acid were additionally formed. The energy efficiency of removal of phenol has been compared with other competitive processes.
-
Granick et al.
, p. 1802,1803 (1940)
-
DUET ELECTROSYNTHESIS OF p-BENZOQUINONE FROM BENZENE
Ito, Sotaro,Iwata, Mikio,Sasaki, Kazuo
, p. 841 - 850 (1991)
The combination of anodic oxidation of benzene using Ag(I)/Ag(II) mediator with cathodic oxidation of benzene using Cu(I)/Cu(II) mediator in a single electrolytic cell produces p-benzoquinone selectively in both anodic and cathodic chambers.
An efficient method for the oxidation of phenolic compounds using new Co(II) and Fe(II) phthalocyanines
Saka, Ece Tugba,?elik, Gonca,Sark?, Gülb?nar,Kantekin, Halit
, p. 161 - 168 (2016)
In this study novel Co(II) and Fe(II) phthalocyanines have been successfully prepared and their structural characterization have been done using with different spectroscopic methods (IR, 1H-NMR, UV–Vis, mass spectroscopies and elemental analysis). Substituted phenolic compounds as substrate, different kinds of oxidants and novel Co(II) and Fe(II) phthalocyanines as catalyst have been used in all oxidation reactions. Temperature, different oxidants, ox./cat. ratio effects on the catalysis have been determined. Interestingly, Co(II) phthalocyanine exhibits superior catalytic activity and durability in the catalysis over oxidation of p-nitrophenol (4-NP). The present method is simple, environmentally benign and amenable scale up process.
Sulfonic-functionalized MIL-101 as bifunctional catalyst for cyclohexene oxidation
Sun, Weng-Jie,Gao, En-Qing
, (2020)
Metal-organic frameworks (MOFs) are newly emerging and versatile platforms for designing catalysts, and catalytic oxidation of cyclohexene has attracted much academic and industrial attention for the versatile reactivity of the substrate and the great importance of the various oxygenated products. Here we report the bifunctional catalytic properties of a sulfonic-containing MOF, MIL-101-SO3H, for cyclohexene oxidation. The sulfonic group and the Cr(III) site acts in a complementary or collaborative way. The Cr(III) framework promotes the oxidation to 3-hydroperoxycyclohex-1-ene (perox) and 2-cyclohexen-1-one (1-one) (route A), whereas the sulfonic group in collaboration with the Cr(III) framework promotes the oxidation to diol (route B) and also enhances further conversions in route A: from perox to 1-one, to 2-cyclohexen-1,4-dione (dione) and even to benzoquinone. With the bifunctional MOF, molecular oxygen alone cannot oxidize cyclohexene but participates as oxidant cooperating with tert-butyl hydroperoxide (TBHP) to accelerate the reactions and to alter the product distribution in favor of dione.
Direct synthesis of phenol from benzene catalyzed by multi-V-POMs complex
Yang, Hua,Wu, Qing,Li, Jun,Dai, Wen,Zhang, Hengyun,Lu, Dan,Gao, Shuang,You, Wansheng
, p. 21 - 25 (2013)
A novel catalyst, [Mo2V2O9(bpy) 6][PMo11VO40], was synthesized by the self-assembling of [PMo11VO40]4- and [Mo 2V2O9(bpy)6]4+ unit and characterized by elemental analyses, TG, IR, X-ray powder diffraction and X-ray single crystal diffraction. [Mo2V2O9(bpy) 6][PMo11VO40] with multi-isolated active sites showed good catalytic activities for hydroxylation of benzene to phenol. A high yield of phenol (25.5%) with selectivity to phenol of 90.7% was obtained using H2O2 as oxidant. The catalyst can be recycled for 5 times while its structure was unchanged and its catalytic activity was maintained.
Oxidative degradation of monomeric and dimeric phenylpropanoids: Reactivity and mechanistic investigation
Canevali, Carmen,Orlandi, Marco,Pardi, Luca,Rindone, Bruno,Scotti, Roberto,Sipila, Jussi,Morazzoni, Franca
, p. 3007 - 3014 (2002)
The oxidative degradation of lignin related model compounds catalysed by [N,N'-bis(salicylidene)ethane-1,2-diaminato]cobalt(II), [Co(salen)], have been studied in chloroform. Arylglycerol β-aryl ethers, phenylcoumarans and apocynol showed very high conversion values within 30 minutes of the start of the reaction and their conversion rates were higher than those reported for phenylpropenoidic compounds, methyl (E)-ferulate and methyl (E)-4-hydroxycinnamate. The results of the CW electron paramagnetic resonance (EPR) investigation using the X-band, performed at the reaction temperature (298 K) showed that two phenoxy cobalt radicals ([CoIII(salen)(ROH)(RO·)] and [CoIII(salen)(RO-)(RO·)]) are involved in the oxidation mechanism of all the phenol compounds ROH. In a frozen solution the [CoIII(salen)(ROH))(RO·)] radical prevailed and its axial magnetic anisotropy was determined using high frequency, 190 GHz, CW EPR spectra. The X-band EPR monitoring of the phenoxy cobalt radicals during the reaction showed a faster decrease in the amounts of radical in the oxidation of propanoidic phenols compared with that of propenoidic phenols. The lifetime of the radicals formed from substrates having a methoxy group ortho to the aromatic hydroxy was also shorter than from substrates lacking this functionality. Both reactivity and spectroscopic data suggest that the lifetime of the phenoxy cobalt radicals correlates with the conversion rates of the substrates.
Application of photoactive electrospun nanofiber materials with immobilized meso-tetraphenylporphyrin for parabens photodegradation
Gmurek,Bizukoj?,Mosinger,Ledakowicz
, p. 160 - 167 (2014)
The pollution of aqueous environment by trace amounts of anthropogenic chemical substances has a hazardous impact on regular development of plants and animals as well as on human health. The paper presents the results of studies on the heterogeneous degradation of butyl- and benzylparaben in aqueous solutions using photochemically catalyzed processes. Meso-tetraphenylporphyrin (TPP) was immobilized in the polyurethane nanofiber material by electro-spinning method. The xenon lamp was used as a simulated sunlight source. The influence of various process parameters on reaction rate was investigated. The reuse of the carrier with the immobilized photosensitizer was examined. The major role of the singlet oxygen (1Δg) during the photodegradation was proved by using sodium azide and radical scavengers. The adsorption isotherms of parabens onto nanofiber material were determined using BET model. The kinetic study showed that the heterogeneous photodegradation of parabens could be modeled using Langmuir-Hinshelwood model and rate constants have been reported. The reaction pathway for the photodegradation of parabens via 1Δg was proposed.
Promoting Effect of TiO2 and Al2O3 Supports on the Activity of Vanadium Oxide Catalyst for the Oxidation of Benzene Measured in Terms of the Turnover Frequency
Inomata, Makoto,Miyamoto, Akira,Murakami, Yuichi
, p. 233 - 234 (1980)
The following relationship, V2O5-TiO2 > unsupported V2O5 > V2O5-Al2O3, was found to hold for the turnover frequency for the oxidation of benzene, which indicates the promoting effect of the TiO2 support on the reaction with vanadium oxide catalyst.
-
Boontanonda,Grigg
, p. 583 (1977)
-
A Chemo-Enzymatic Cascade for the Smart Detection of Nitro- and Halogenated Phenols
Watthaisong, Pratchaya,Pongpamorn, Pornkanok,Pimviriyakul, Panu,Maenpuen, Somchart,Ohmiya, Yoshihiro,Chaiyen, Pimchai
, p. 13254 - 13258 (2019)
The flavin-dependent monooxygenase, HadA, catalyzes the dehalogenation and denitration of the toxicants, nitro- and halogenated phenols, to benzoquinone. The HadA reaction can be applied in one-pot reactions towards the de novo synthesis of d-luciferin by coupling with d-Cys condensation. d-luciferin, a valuable chemical widely used in biomedical applications, can be used as a substrate for the reaction of firefly luciferase to generate bioluminescence. As nitro- and halogenated phenols are key indicators of human overexposure to pesticides and pesticide contamination, the technology provides a sensitive and convenient tool for improved biomedical and environmental detection at ppb sensitivity in biological samples without the requirement for any pre-treatment. This dual-pronged method combines the advantages of waste biodetoxification to produce a valuable chemical as well as a smart detection tool for environmental and biomedical detection.
Electron-transfer oxidation of chlorophenols by uranyl ion excited state in aqueous solution. Steady-state and Nanosecond flash photolysis studies
Sarakha, Mohamed,Bolte, Michele,Burrows, Hugh D.
, p. 3142 - 3149 (2000)
The oxidation of chlorophenols by photoexcited uranyl ion was studied in aqueous solution at concentrations where the ground-state interactions were negligible. Nanosecond flash photolysis showed that a clean electron-transfer process from the chlorophenols to the excited uranyl ion is involved. This is suggested to lead to the formation of a U(V)/chlorophenoxyl radical pair complex. The efficiency of this charge-transfer process is unity for the three chlorophenols. However, low product yields suggest that in the absence of oxygen, back electron transfer, both within the radical pair and from separated uranium(V) to phenoxyl radicals, appears to be the major reaction pathway. In the presence of oxygen the quantum yields of disappearance of chlorophenol and of photoproduct formation increased. This leads to the conclusion that oxygen favors reaction with uranium(V) and/or the uranium(V) - phenoxyl radical pair, leading to the formation of the superoxide anion and its conjugate acid, HO2*, which then regenerate UO22+. Based on this, a catalytic cycle for chlorophenol photooxidation involving uranyl ion and molecular oxygen is proposed.
Electrochemical incineration of 4-chlorophenol and the identification of products and intermediates by mass spectrometry
Johnson, Steve K.,Houk, Linda L.,Feng, Jianren,Houk,Johnson, Dennis C.
, p. 2638 - 2644 (1999)
This report summarizes results obtained as part of a larger effort to demonstrate the applicability of electrolytic procedures for the direct anodic (oxidative) degradation of toxic organic wastes. We refer to this process as "electrochemical incineration" (ECI) because the ultimate degradation products, e.g., carbon dioxide, are equivalent to those achieved by thermal incineration processes. In this work, the ECI of 4-chlorophenol is achieved in an aqueous medium using a platinum anode coated with a quaternary metal oxide film containing Ti, Ru, Sn, and Sb oxides. The electrode is stable and active when used with a solid Nafion membrane without the addition of soluble supporting electrolyte. Liquid chromatography (LC), including reverse phase and ion exchange chromatography, is coupled with electrospray mass spectrometry (ES-MS) and used, along with gas chromatography-mass spectrometry (GC-MS) and measurements of pH, chemical oxygen demand (COD), and total organic carbon (TOC), to study the reaction and identify the intermediate products from the ECI of 4-chlorophenol. Twenty-six intermediate products are identified and reported. The most abundant of these products are benzoquinone, 4-chlorocatechol, maleic acid, succinic acid, malonic acid, and the inorganic anions chloride, chlorate, and perchlorate. After 24 h of ECI, a solution that initially contained 108 ppm 4-chlorophenol yields only 1 ppm TOC with 98% of the original chlorine remaining in the specified inorganic forms. LC-ES-MS and direct infusion ES-MS detection limits are between 80 ppb and 4 ppm for these intermediate products. Elemental analysis of the electrolyzed solutions by inductively coupled plasma mass spectrometry ICP-MS showed that only trace amounts (25 ppb) of the metallic elements comprising the metal oxide film were present in the solution.
Hydrolysis of N-Acetyl-p-benzoquinone Imines: pH Dependence of the Partitioning of a Tetrahedral Intermediate
Novak, Michael,Bonham, Gayl A.,Mulero, Julio J.,Pelecanou, Maria,Zemis, Joseph N.,et al.
, p. 4447 - 4456 (1989)
The hydrolysis reactions of N-acetyl-p-benzoquinone imine, 1a, and its 3,5- and 2,6-dimethyl analogues, 1b and 1c, in the pH range 0.3-10.5 are described.At pH 6.0 the carbinolamide intermediates 2a-c can be detected by 1H NMR, UV, and HPLC methods.The pH-dependent partitioning of 2a and 2c can be monitored since the reversion of these intermediates to the protonated N-acylimines 5a and 5c leads to products of the conjugate attack of Cl(-), the 3-chloroacetaminophen derivatives 4a and 4c.A mechanism for the hydrolysis of 1a-c (Scheme I) is proposed which accurately predicts the time dependence of the formation of 2 and the final hydrolysis products, the p-benzoquinones 3, and 4.The alternative O-protonation mechanism (Scheme II) is tentatively rejected on the basis of substituent effect data.The relationship of the hydrolysis reactions of 1a-c to those of ordinary imines is discussed.
Thermodynamics of Disproportionation and Heats of Hydration of 1,4-Benzosemiquinone and 1,4-Naphthosemiquinone at pH 7.1
Alegria, Antonio E.,Munoz, Carlos,Rodriguez, Maria S.
, p. 930 - 934 (1990)
The thermodynamics of disproportionation of 1,4-benzosemiquinone (BQ*-) and 1,4-naphthosemiquinone (NQ*-) in cacodylic-cacodylate buffer at pH 7.1 was studied by spin resonance (ESR) spectroscopy and solution calorimetry.The disproportionation of BQ*- was found to be more exergonic and exothermic than that corresponding to NQ*- in both aqueous and gas phases.These semiquinones disproportionate about 40 times more exothermically in the gaseous than in the aqueous phase.The differences between the enthalpies of disproportionation corresponding to BQ*- and NQ*- are 51 and 14 kJ/mol in the gaseous and aqueous phases, respectively.The heats of hydration of BQ*- and NQ*- were determined with a convenient thermochemical cycle based on the enthalpies of disproportionation.The single-ion heats of hydration of BQ*- and NQ*- were found to be -360 and -377 kJ/mol, respectively.The heats of hydration of the net negative charge in BQ*- and NQ*- were found to be the same.
On the photocatalytic degradation of phenol and dichloroacetate by BiVO4: The need of a sacrificial electron acceptor
Castillo, Nikola C.,Ding, Laura,Heel, Andre,Graule, Thomas,Pulgarin, Cesar
, p. 221 - 227 (2010)
The photodegradation of phenol and dichloroacetic acid (DCAA) by BiVO 4 was studied in the absence as well as presence of selected electron scavengers. The experiments were performed under the visible (vis) irradiation of aqueous solutions over a wide pH range (1-13). Phenol was photocatalytically degraded by BiVO4 into p-benzoquinone below pH 3 and into an open-ring structure at pH 13. Methylene blue (MB) accelerated the reaction below the isoelectric point of BiVO4 and did not undergo significant degradation. In presence of H2O2, phenol was rapidly degraded up to pH 9. The degradation rates are two orders of magnitude higher than in absence of electron scavenger. The degradation of dichloroacetic acid was only possible in presence of H2O2. High initial concentrations of H2O2 inhibit the reaction and its consumption is very fast. Sequential additions of this sacrificial electron acceptor (SEA) enables the total degradation of a 1 mM DCAA solution.
Photocatalytic removal of benzene over Ti3C2T: XMXene and TiO2-MXene composite materials under solar and NIR irradiation
Calvino, José J.,Constantinescu, Gabriel,Frade, Jorge R.,Kovalevsky, Andrei V.,Labrincha, Jo?o A.,Lajaunie, Luc,Lopes, Daniela V.,Sergiienko, Sergii A.,Shaula, Aliaksandr L.,Shcherban, Nataliya D.,Shkepu, Viacheslav I.,Tobaldi, David M.
, p. 626 - 639 (2022/01/22)
MXenes, a family of two-dimensional (2D) transition metal carbides, nitrides and carbonitrides based on earth-abundant constituents, are prospective candidates for energy conversion applications, including photocatalysis. While the activity of individual MXenes towards various photocatalytic processes is still debatable, these materials were proved to be excellent co-catalysts, accelerating the charge separation and suppressing the exciton recombination. Titanium-containing MXenes are well compatible with the classical TiO2 photocatalyst. The TiO2 component can be directly grown on MXene sheets by in situ oxidation, representing a mainstream processing approach for such composites. In this study, an essentially different approach has been implemented: a series of TiO2-MXene composite materials with controlled composition and both reference end members were prepared, involving two different strategies for mixing sol-gel-derived TiO2 nanopowder with the Ti3C2Tx component, which was obtained by HF etching of self-propagating high-temperature synthesis products containing modified MAX phase Ti3C2Alz (z > 1) with nominal aluminium excess. The prospects of such composites for the degradation of organic pollutants under simulated solar light, using benzene as a model system, were demonstrated and analysed in combination with their structural, microstructural and optical properties. A notable photocatalytic activity of bare MXene under near infrared light was discovered, suggesting further prospects for light-to-energy harvesting spanning from UV-A to NIR and applications in biomedical imaging and sensors.
Direct catalytic benzene hydroxylation under mild reaction conditions by using a monocationic μ-nitrido-bridged iron phthalocyanine dimer with 16 peripheral methyl groups
Tanaka, Kentaro,Teoh, Chee-Ming,Toyoda, Yuka,Yamada, Yasuyuki
supporting information, p. 955 - 958 (2022/02/07)
Direct catalytic hydroxylation of benzene under mild reaction conditions proceeded efficiently in the presence of a monocationic μ-nitrido-bridged iron phthalocyanine dimer with 16 peripheral methyl groups in an acetonitrile solution with excess H2O2. Mechanistic studies suggested that the reaction was catalyzed by a high-valent iron-oxo species generated in situ. Moreover, the peripheral methyl groups of the catalyst were presumed to have enhanced the production rate of the iron-oxo species.
