176220-38-5Relevant articles and documents
Semiconductor-based interfacial electron-transfer reactivity: Decoupling kinetics from pH-dependent band energetics in a dye-sensitized titanium dioxide/aqueous solution system
Yan, Susan G.,Hupp, Joseph T.
, (1996)
Hexaphosphonation of Ru(bpy)32+ provides a basis for surface attachment to nanocrystalline TiO2 in film (electrode) or colloidal form and for subsequent retention of the molecule over an extraordinarily wide pH range. Visible excitation of the surface-attached complex leads to rapid injection of an electron into the semiconductor. Return electron transfer, monitored by transient absorbance spectroscopy, is biphasic with a slow component that can be reversibly eliminated by adjusting the potential of the dark electrode to a value close to the conduction-band edge (ECB). Evaluation of the fast component yields a back-electron-transfer rate constant of 5(±0.5) × 107 s-1 that is invariant between pH = 11 and H0 = -8, despite a greater than 1 eV change in ECB (i.e., the nominal free energy of the electron in the electrode). The observed insensitivity to large changes in band-edge energetics stands in marked contrast to the behavior expected from a straightforward application of conventional interfacial electron-transfer theory and calls into question the existing interpretation of these types of reactions as simple inverted region processes.
Highly selective and durable photochemical co2 reduction by molecular mn(i) catalyst fixed on a particular dye-sensitized TiO2 Platform
Woo, Sung-Jun,Choi, Sunghan,Kim, So-Yoen,Kim, Pil Soo,Jo, Ju Hyoung,Kim, Chul Hoon,Son, Ho-Jin,Pac, Chyongjin,Kang, Sang Ook
, p. 2580 - 2593 (2019/03/08)
A Mn(I)-based hybrid system (OrgD-|TiO2|-MnP) for photocatalytic CO2 reduction is designed to be a coassembly of Mn(4,4′-Y2-bpy)(CO)3Br (MnP; Y = CH2PO(OH)2) and (E)-3-[5-(4-(diphenylamino)phenyl)-2,2′-bithiophen-2′-yl]-2-cyanoacrylic acid (OrgD) on TiO2 semiconductor particles. The OrgD-|TiO2|-MnP hybrid reveals persistent photocatalytic behavior, giving high turnover numbers and good product selectivity (HCOO- versus CO). As a typical run, visible-light irradiation of the hybrid catalyst in the presence of 0.1 M electron donor (ED) and 0.001 M LiClO4 persistently produced HCOO- with a >99% selectivity accompanied by a trace amount of CO; the turnover number (TONformate) reached ?250 after 23 h of irradiation. The product selectivity (HCOO-/CO) was found to be controlled by changing the loading amount of MnP on the TiO2 surface. In situ FTIR analysis of the hybrid during photocatalysis revealed that, at low Mn concentration, the Mn-H monomeric mechanism associated with HCOO- formation is dominant, whereas at high Mn concentration, CO is formed via a Mn-Mn dimer mechanism.
Synthesis and characterization of novel heteroleptic Ru(II) bipyridine complexes for dye-sensitized solar cell applications
Seo, Jinhyung,Jeong, Mingyeong,Na, Seo Yeong,Lee, Eugin,Kim, Yang-Rae,Park, Byoungchoo,Kim, Byeong Hyo
, p. 1445 - 1452 (2019/07/29)
Abstract: Four heteroleptic ruthenium(II) complexes, [Ru(L1)(L2)(NCS)2] (where L1 = 4,4′-bis[2-(1,1′-biphenyl)-4-ylethenyl]-2,2′-bipyridine (bpbpy) or 4,4′-bis[2-(3,4-dimethoxyphenyl)ethenyl]-2,2′-bipyridine (dmpbpy); L2 = 4,4′-dicarboxy-2,2′-bipyridine (dcbpy) or 4,4′-bis(E-carboxyvinyl)-2,2′-bipyridine (dcvbpy)), were synthesized from a one-pot reaction of [RuCl2(p-cymene)]2 and L1 followed by the addition of the anchoring ligand, L2. From these new heteroleptic ruthenium(II) complexes containing carboxylic acid-functionalized ligands, the tetrabutylammonium salt forms of the ruthenium(II) complexes, [Ru(L1)(L2)(NCS)2][TBA], were obtained in reasonable yields and applied as dyes in dye-sensitized solar cell (DSSC) devices. Among the DSSCs fabricated with the [Ru(L1)(L2)(NCS)2][TBA] dyes, a DSSC fabricated with the [Ru(bpbpy)(dcbpy)(NCS)2][TBA] dye exhibited the best power conversion efficiency (η) of 4.27%, while the cells fabricated with other dyes had η between 1.94 and 2.68%. Graphic abstract: [Figure not available: see fulltext.].
Synthesis and Characterization of Heteroleptic Ru(II) Complexes Based on 4,4′-Bis((E)-styryl)-2,2′-bipyridine as Ancillary Ligand and Application for Dye-Sensitized Solar Cells
Lee, Jihoon,Seo, Jinhyung,Choi, Yong Rack,Oh, Hyunju,Huh, Jun Nyeong,Park, Byoungchoo,Tak, Jungae,Kim, Byeong Hyo
, (2018/06/11)
Heteroleptic Ru(II) complexes were designed based on 4,4′-bis((E)-styryl)-2,2′-bipyridine (bsbpy) as an ancillary ligand for dye-sensitized solar cells (DSSCs), and those Ru(II) sensitizers, [Ru(L)(bsbpy)(NCS)2][TBA] (TBA; tetrabutylammonium), were synthesized according to a typical one-pot reaction of [RuCl2(p-cymene)]2 with the corresponding anchoring ligands (where L?=?4,4′-dicarboxy-2,2′-bipyridine (dcbpy), 4,4′-bis((E)-carboxyvinyl)-2,2′-bipyridine (dcvbpy), 4,7-dicarboxy-1,10-phenanthroline (dcphen), or 4,7-bis((E)-carboxyvinyl)-1,10-phenanthroline (dcvphen)). The new Ru(II) dyes, [Ru(L)(bsbpy)(NCS)2][TBA] that incorporated vinyl spacer(s) into ancillary and/or anchoring ligand displayed red-shifted bands over the overall UV/VIS region relative to the absorption spectra of N719. A combination of bsbpy ancillary and dcphen anchoring ligand showed the best result for the overall power conversion efficiency (η); i.e., a DSSC fabricated with [Ru(dcphen)(bsbpy)(NCS)2][TBA] exhibited a power conversion efficiency (η) of 2.98% (compare to N719, 4.82%).
Directly Coupled Versus Spectator Linkers on Diimine PtII Acetylides—Change the Structure, Keep the Function?
Archer, Stuart A.,Keane, Theo,Delor, Milan,Bevon, Elizabeth,Auty, Alexander J.,Chekulaev, Dimitri,Sazanovich, Igor V.,Towrie, Michael,Meijer, Anthony J. H. M.,Weinstein, Julia A.
, p. 18239 - 18251 (2017/12/07)
Modification of light-harvesting units with anchoring groups for surface attachment often compromises light-harnessing properties. Herein, a series of [donor–acceptor–anchor] platinum(II) diimine (bis-)acetylides was developed in order to systematically compare the effect of conjugated versus electronically decoupled modes of attachment of protected anchoring groups on the photophysical properties of light-harvesting units. The first examples of “decoupled” phosphonate diimine PtII complexes are reported, and their properties are compared and contrasted to those of carboxylate analogues studied by a diversity of methods. Ultrafast time-resolved IR and transient absorption spectroscopy revealed that all complexes have a charge-transfer (CT) lowest excited state with lifetimes between 2 and 14 ns. Vibrational signatures and dynamics of CT states were identified; the assignment of electronic states and their vibrational origin was aided by TDDFT calculations. Ultrafast energy redistribution accompanied by structural changes was directly captured in the CT states. A significant difference between the structures of the electronic ground and CT excited states, as well as differences in the structural reorganisation in the complexes bearing directly attached or electronically decoupled anchoring groups, was discovered. This work demonstrates that decoupling of the anchoring group from the light-harvesting core by a saturated spacer is an easy approach to combine surface attachment with high reduction potential and ten times longer lifetime of the CT excited state of the light-absorbing unit, and retain electron-transfer photoreactivity essential for light-harvesting applications.
Nanosecond transient absorption spectroscopy of a Ru polypyridine phenothiazine dyad
Kosgei, Gilbert K.,Livshits, Maksim Y.,Canterbury, Theodore R.,Rack, Jeffery J.,Brewer, Karen J.
supporting information, p. 67 - 70 (2016/11/22)
A bipyridine phenothiazine ligand [(PTZEtv2bpy) and metal complexes [Ru(Ph2phen)3]2+(1), [(Ph2phen)2Ru(PTZEtv2bpy)]2+(2), and [(PTZEtv2bpy)(Ph2ph
A water-soluble and retrievable ruthenium-based probe for colorimetric recognition of Hg(II) and Cys
Cui, Yali,Hao, Yuanqiang,Zhang, Yintang,Liu, Baoxia,Zhu, Xu,Qu, Peng,Li, Deliang,Xu, Maotian
, p. 150 - 154 (2016/05/09)
A new ruthenium-based complex 1 [(bis(4,4′-dimethylphosphonic-2,2′-bipyridine) dithiocyanato ruthenium (II))] was developed as a colorimetric probe for the detection of Hg(II) and Cys (Cysteine). The obtained compound 1 can give interconversional color changes upon the alternating addition of Hg(II) and Cys in 100% aqueous solution. The specific coordination between NCS groups with Hg(II) can lead to the formation of 1-Hg2 + complex, which can induce a remarkable spectral changes of probe 1. Afterwards the formed 1-Hg2 + complex can act as effective colorimetric sensor for Cys. Owing to the stronger binding affinity of sulfhydryl group to Hg2 +, Cys can extract Hg2 + from 1-Hg2 + complex resulting in the release of 1 and the revival of absorption profile of the probe 1. By introducing the hydrophilic phosphonic acid groups, the proposed probe exhibited excellent water solubility. The limits of detection (LODs) of the assay for Hg2 + and Cys are calculated to be 15 nM and 200 nM, respectively.
Metal-based tris-bipyridyl complexes and uses thereof in electrochromic applications
-
, (2016/10/09)
The present invention relates to metal-based tris-bipyridyl complexes, e.g., iron-based tris-bipyridyl complexes, and their use in fabrication of surface confined assemblies for electrochromic applications.
Copper oxide surfaces modified by alkylphosphonic acids with terminal pyridyl-based ligands as a platform for supported catalysis
Andrews, Brooke,Almahdali, Sarah,James, Karmel,Ly, Sandrine,Crowder, Katherine N.
, p. 360 - 369 (2016/07/06)
Self-assembled monolayer (SAM) films of phosphonates have been successfully formed via reaction of 11-hydroxyundecylphosphonic acid or 4,4′-di(methylenephosphonic acid)-2,2′-bipyridine with the oxide layer of copper via the Tethering by Aggregation and Growth (TBAG) deposition method. The hydroxyl-terminated SAM was further modified with isonicotinic acid or 4,4′-dicarboxy-2,2′-bipyridine through a Steglich esterification reaction. These three surfaces derivatized with pyridyl-based ligands are potential platforms for supported catalysis. As a proof of concept, [Ru(CO)3Cl2]2 was bound to the surfaces through the pyridyl-based ligands to yield tethered analogs of the known carbon dioxide reduction catalyst, [Ru(bpy)(CO)2Cl2]. Surface modification reactions were confirmed through specular reflectance infrared (IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Characteristic core binding energies were observed in the XPS analyses for phosphorus (P 2p), nitrogen (N 1s), and ruthenium (Ru 3p and Ru 3d), verifying the presence of the various surface functionalizations. IR and XPS data indicate that the phosphonate binding to the copper surface is tridentate in nature.
Synthesis and characterization of an immobilizable photochemical molecular device for H2-generation
Braumüller, Markus,Schulz, Martin,Sorsche, Dieter,Pfeffer, Michael,Schaub, Markus,Popp, Jürgen,Park, Byung-Wook,Hagfeldt, Anders,Dietzek, Benjamin,Rau, Sven
, p. 5577 - 5586 (2015/03/30)
With [RuII(bpyMeP)2tpphzPtCl2]2+ (4) a molecular photocatalyst has been synthesized for visible-light-driven H2-evolution. It contains the ligand bpyMeP (4,4′-bis(diethyl-(methylene)-phosphonate)-2,2′-bipyridine) with phosphate ester groups as precursors for the highly potent phosphonate anchoring groups, which can be utilized for immobilization of the catalyst on metal-oxide semiconductor surfaces. The synthesis was optimized with regard to high yields, bpyMeP was fully characterized and a solid-state structure could be obtained. Photophysical studies showed that the photophysical properties and the localization of the excited states are not altered compared to similar Ru-complexes without anchoring group precursors. (4) was even more active in homogenous catalysis experiments than [RuII(tbbpy)2tpphzPtCl2]2+ (6) with tbbpy (4,4′-bis(tbutyl)-2,2′-bipyridine) as peripheral ligands. After hydrolysis (4) was successfully immobilized on NiO, suggesting that an application in photoelectrosynthesis cells is feasible. This journal is
