The Experts below are selected from a list of 11925 Experts worldwide ranked by ideXlab platform
Xinchen Wang - One of the best experts on this subject based on the ideXlab platform.
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imidazolium ionic liquids imidazolylidene heterocyclic carbenes and zeolitic imidazolate frameworks for co2 capture and Photochemical Reduction
ChemInform, 2016Co-Authors: Sibo Wang, Xinchen WangAbstract:Review: [recent developments and existing shortcomings of imidazolate motifs for CO2 utilization, with focus on CO2 photoReduction catalysis, 64 refs.
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imidazolium ionic liquids imidazolylidene heterocyclic carbenes and zeolitic imidazolate frameworks for co2 capture and Photochemical Reduction
Angewandte Chemie, 2016Co-Authors: Sibo Wang, Xinchen WangAbstract:Imidazolium ionic liquids (ILs), imidazolylidene N-heterocyclic carbenes (NHCs), and zeolitic imidazolate frameworks (ZIFs) are imidazolate motifs which have been extensively investigated for CO2 adsorption and conversion applications. Summarized in this minireview is the recent progress in the capture, activation, and Photochemical Reduction of CO2 with these three imidazolate building blocks, from homogeneous molecular entities (ILs and NHCs) to heterogeneous crystalline scaffolds (ZIFs). The developments and existing shortcomings of the imidazolate motifs for their use in CO2 utilizations is assessed, with more of focus on CO2 photoredox catalysis. The opportunities and challenges of imidazolate scaffolds for future advancement of CO2 Photochemical conversion for artificial photosynthesis are discussed.
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a stable znco2o4 cocatalyst for photocatalytic co2 Reduction
Chemical Communications, 2015Co-Authors: Sibo Wang, Zhengxin Ding, Xinchen WangAbstract:Spinel ZnCo2O4 nanostructures have shown great opportunities in energy related areas. However, the applications of ZnCo2O4 for the conversion of CO2 are much less reported. Herein, we present the use of mesoporous ZnCo2O4 nanorods as efficient and high stable cocatalysts for the Photochemical Reduction of CO2 under mild reaction conditions.
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semiconductor redox catalysis promoted by metal organic frameworks for co2 Reduction
Physical Chemistry Chemical Physics, 2014Co-Authors: Sibo Wang, Jinliang Lin, Xinchen WangAbstract:A noble-metal-free system for Photochemical Reduction of CO2 has been developed by integrating graphitic carbon nitride (g-C3N4) with a cobalt-containing zeolitic imidazolate framework (Co-ZIF-9). g-C3N4 acts as a semiconductor photocatalyst, whereas Co-ZIF-9 is a cocatalyst that facilitates the capture/concentration of CO2 and promotes light-induced charge separation. The two materials cooperate efficiently to catalyze CO2-to-CO conversion upon visible light illumination under mild reaction conditions. A 13C-labelled isotropic experiment proved that CO2 is the carbon source of the produced CO. Even without noble metals, the system still achieved an apparent quantum yield of 0.9 percent. The system displayed high photocatalytic stability, without noticeable alterations in the chemical and crystal structures of g-C3N4 and Co-ZIF-9 after the reaction.
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Photochemical Reduction of co2 by graphitic carbon nitride polymers
ACS Sustainable Chemistry & Engineering, 2014Co-Authors: Jinliang Lin, Zhiming Pan, Xinchen WangAbstract:The combination of cobalt redox catalysis and carbon nitride photocatalysis to construct a cascade photoreaction system has been developed for the deoxygenative Reduction of CO2 to CO with visible light. The graphitic carbon nitride has been demonstrated to function both as a capture/activation substrate of CO2 and a photocatalyst, whereas the introduced cobalt species act as reductive and oxidative promoters to accelerate charge-carrier separation and transfer kinetics. This hybrid photosystem contains inexpensive substances that synergetically catalyze CO2-to-CO conversion at mild conditions, with a high stability of catalysts. The optimization in the surface and texture structures as well as reaction conditions has been demonstrated. The results represent an important step toward artificial photosynthesis by using cost-acceptable materials.
Osamu Ishitani - One of the best experts on this subject based on the ideXlab platform.
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Data_Sheet_1_An Ir(III) Complex Photosensitizer With Strong Visible Light Absorption for Photocatalytic CO2 Reduction.pdf
2019Co-Authors: Yusuke Kuramochi, Osamu IshitaniAbstract:A cyclometalated iridium(III) complex having 2-(pyren-1-yl)-4-methylquinoline ligands [Ir(pyr)] has a strong absorption band in the visible region (ε444nm = 67,000 M−1 cm−1) but does not act as a photosensitizer for Photochemical Reduction reactions in the presence of triethylamine as an electron donor. Here, 1,3-dimethyl-2-(o-hydroxyphenyl)-2,3-dihydro-1H-benzo[d]imidazole (BI(OH)H) was used instead of the amine, demonstrating that BI(OH)H efficiently quenched the excited state of Ir(pyr) and can undergo the Photochemical carbon dioxide (CO2) Reduction catalyzed by trans(Cl)-Ru(dmb)(CO)2Cl2 (dmb = 4,4′-dimethyl-2,2′-bipyridine, Ru) to produce formate as the main product. We also synthesized a binuclear complex combining Ir(pyr) and Ruvia an ethylene bridge and investigated its Photochemical CO2 Reduction activity in the presence of BI(OH)H.
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An Ir(III) Complex Photosensitizer With Strong Visible Light Absorption for Photocatalytic CO2 Reduction
Frontiers Media S.A., 2019Co-Authors: Yusuke Kuramochi, Osamu IshitaniAbstract:A cyclometalated iridium(III) complex having 2-(pyren-1-yl)-4-methylquinoline ligands [Ir(pyr)] has a strong absorption band in the visible region (ε444nm = 67,000 M−1 cm−1) but does not act as a photosensitizer for Photochemical Reduction reactions in the presence of triethylamine as an electron donor. Here, 1,3-dimethyl-2-(o-hydroxyphenyl)-2,3-dihydro-1H-benzo[d]imidazole (BI(OH)H) was used instead of the amine, demonstrating that BI(OH)H efficiently quenched the excited state of Ir(pyr) and can undergo the Photochemical carbon dioxide (CO2) Reduction catalyzed by trans(Cl)-Ru(dmb)(CO)2Cl2 (dmb = 4,4′-dimethyl-2,2′-bipyridine, Ru) to produce formate as the main product. We also synthesized a binuclear complex combining Ir(pyr) and Ruvia an ethylene bridge and investigated its Photochemical CO2 Reduction activity in the presence of BI(OH)H
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electrons photons protons and earth abundant metal complexes for molecular catalysis of co2 Reduction
ACS Catalysis, 2017Co-Authors: Hiroyuki Takeda, Osamu Ishitani, Claudio Cometto, Marc RobertAbstract:Electrochemical and Photochemical Reduction of CO2, or a smart combination of both, are appealing approaches for the storage of renewable, intermittent energies and may lead to the production of fuels and of value-added chemicals. By using only earth-abundant metal (Cu, Ni, Co, Mn, Fe) complexes, cheap electrodes and/or cheap sacrificial electron donors and visible light sensitizers, systems functioning with molecular catalysts have been recently designed, showing promising results, in particular, for the two-electron Reduction of the carbon dioxide. By combining experimental and mechanistic studies, key parameters controlling the catalysis efficiency have been deciphered, opening the way to the design of future, more efficient and durable catalysts, as well as to the development of electrochemical or photoelectrochemical cells, all being key steps for the emergence of applied devices. The most recent advances related to these issues are discussed in this review.
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iridium iii 1 phenylisoquinoline complexes as a photosensitizer for photocatalytic co2 Reduction a mixed system with a re i catalyst and a supramolecular photocatalyst
Inorganic Chemistry, 2016Co-Authors: Yusuke Kuramochi, Osamu IshitaniAbstract:An Ir(III) complex with 1-phenylisoquinoline (piq) ligands [Ir(piq)2(dmb)]+ (Ir, dmb = 4,4′-dimethyl-2,2′-bipyridine) exhibited strong absorption in the visible region, and the lifetime of its excited state was very long (τ = 2.8 μs). Photochemical Reduction of Ir efficiently proceeded with 1-benzyl-1,4-dihydronicotinamide (BNAH) and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (BIH) as reductants, giving the one-electron-reduced species (OERS), which was stable in solution at ambient temperature. The OERS of the Ir complex possessed strong reductive power, sufficient to supply an electron to fac-Re(dmb)(CO)3Br (Re). The photocatalytic Reduction of CO2 proceeded efficiently using a mixed system constructed with Ir as a redox photosensitizer and Re as a catalyst, selectively giving CO (ΦCO = 0.16 using BNAH at λex = 480 nm). Ir was a more suitable photosensitizer for evaluating the activity of the Re catalyst in the photocatalytic reaction compared to [Ru(dmb)3]2+ (Ru) because the Ir complex was ...
Christopher N. Bowman - One of the best experts on this subject based on the ideXlab platform.
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spatial and temporal control of the alkyne azide cycloaddition by photoinitiated cu ii Reduction
Nature Chemistry, 2011Co-Authors: Brian J Adzima, Christopher J. Kloxin, Youhua Tao, Cole A Deforest, Kristi S Anseth, Christopher N. BowmanAbstract:The click reaction paradigm is focused on the development and implementation of reactions that are simple to perform while being robust and providing exquisite control of the reaction and its products. Arguably the most prolific and powerful of these reactions, the copper-catalysed alkyne-azide reaction (CuAAC) is highly efficient and ubiquitous in an ever increasing number of synthetic methodologies and applications, including bioconjugation, labelling, surface functionalization, dendrimer synthesis, polymer synthesis and polymer modification. Unfortunately, as the Cu(I) catalyst is typically generated by the chemical Reduction of Cu(II) to Cu(I), or added as a Cu(I) salt, temporal and spatial control of the CuAAC reaction is not readily achieved. Here, we demonstrate catalysis of the CuAAC reaction via the Photochemical Reduction of Cu(II) to Cu(I), affording comprehensive spatial and temporal control of the CuAAC reaction using standard photolithographic techniques. Results reveal the diverse capability of this technique in small molecule synthesis, patterned material fabrication and patterned chemical modification.
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spatial and temporal control of the alkyne azide cycloaddition by photoinitiated cu ii Reduction
Nature Chemistry, 2011Co-Authors: Brian J Adzima, Christopher J. Kloxin, Cole A Deforest, Kristi S Anseth, Christopher N. BowmanAbstract:The copper(I)-catalysed azide–alkyne cycloaddition is arguably the most prolific and powerful example of the click reaction paradigm. Here, Photochemical Reduction of Cu(II) allows spatial and temporal control over the reaction for small-molecule synthesis, patterning of hydrogel formation and the in situ labelling of gels, with features as small as 25 micrometres being produced.
Kristi S Anseth - One of the best experts on this subject based on the ideXlab platform.
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spatial and temporal control of the alkyne azide cycloaddition by photoinitiated cu ii Reduction
Nature Chemistry, 2011Co-Authors: Brian J Adzima, Christopher J. Kloxin, Youhua Tao, Cole A Deforest, Kristi S Anseth, Christopher N. BowmanAbstract:The click reaction paradigm is focused on the development and implementation of reactions that are simple to perform while being robust and providing exquisite control of the reaction and its products. Arguably the most prolific and powerful of these reactions, the copper-catalysed alkyne-azide reaction (CuAAC) is highly efficient and ubiquitous in an ever increasing number of synthetic methodologies and applications, including bioconjugation, labelling, surface functionalization, dendrimer synthesis, polymer synthesis and polymer modification. Unfortunately, as the Cu(I) catalyst is typically generated by the chemical Reduction of Cu(II) to Cu(I), or added as a Cu(I) salt, temporal and spatial control of the CuAAC reaction is not readily achieved. Here, we demonstrate catalysis of the CuAAC reaction via the Photochemical Reduction of Cu(II) to Cu(I), affording comprehensive spatial and temporal control of the CuAAC reaction using standard photolithographic techniques. Results reveal the diverse capability of this technique in small molecule synthesis, patterned material fabrication and patterned chemical modification.
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spatial and temporal control of the alkyne azide cycloaddition by photoinitiated cu ii Reduction
Nature Chemistry, 2011Co-Authors: Brian J Adzima, Christopher J. Kloxin, Cole A Deforest, Kristi S Anseth, Christopher N. BowmanAbstract:The copper(I)-catalysed azide–alkyne cycloaddition is arguably the most prolific and powerful example of the click reaction paradigm. Here, Photochemical Reduction of Cu(II) allows spatial and temporal control over the reaction for small-molecule synthesis, patterning of hydrogel formation and the in situ labelling of gels, with features as small as 25 micrometres being produced.
Dimosthenis L Giokas - One of the best experts on this subject based on the ideXlab platform.
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paper based devices for biothiols sensing using the Photochemical Reduction of silver halides
Analytica Chimica Acta, 2018Co-Authors: Foteini A Kappi, George Z Tsogas, Annamaria Routsi, Dionysios C Christodouleas, Dimosthenis L GiokasAbstract:Abstract This study describes the development of paper-based devices for the determination of biothiols. The devices are inexpensive (composed of paper and silver halide particles), and the analytical protocol is easily executable with minimum technical expertise and without the need of specialized equipment; the user has to add a test sample, illuminate the device with a UV lamp, and read the color change of the sensing area using a simple imaging device (i.e., cell-phone camera) or a bare eye. The detection mechanism of the assay is based on the biothiols-mediated photoReduction of nanometer-sized silver chloride particles deposited on the surface of paper; photoreduced silver chloride particles have a grayish coloration that depends on the concentration of biothiols in the tested solution. This is the first time that the UV-mediated photoReduction of solid silver halides particles is used for analytical purposes. The performance of the devices has been tested on the detection of total biothiols content of artificial body fluids and protein–free human blood plasma samples, and the results were satisfactory in terms of sensitivity, selectivity, recoveries and reproducibility.
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low cost colorimetric assay of biothiols based on the Photochemical Reduction of silver halides and consumer electronic imaging devices
Talanta, 2017Co-Authors: Foteini A Kappi, George Z Tsogas, George A Papadopoulos, Dimosthenis L GiokasAbstract:Abstract This work describes a new approach for the determination of free biothiols in biological fluids that exploits some of the basic principles of early photographic chemistry — that was based on silver-halide recording materials — and uses broadly-available imaging devices (i.e. flatbed scanners) as detectors. Specifically, the proposed approach relies on the ability of biothiols to bind to silver ions and dissociate the silver halide crystals thus changing the photosensitivity of silver halide crystal suspension. The changes induced by biothiols on the light intensity transmitted through the silver halide suspension, after Photochemical Reduction, were measured with a simplified photometric approach that employs a flatbed scanner operating in transmittance mode. The overall analytical procedure for the determination of biothiols was easily executable, fast and could be applied with inexpensive and commercially available materials and reagents. What is more, physiologically relevant biothiol levels could be inspected even by the unattended eye. The developed assay was successfully applied to the determination of biothiols in urine and blood plasma samples with detection limits as low as 10 μM, satisfactory recoveries (92–97%), good reproducibility (6.7–8.8%) and high selectivity against other major components of biological fluids. The utility of the method to the determination of reduced/oxidized thiol ratio's as well as its application under natural light illumination, without external energy sources, was also demonstrated and is discussed with regard to point-of need applications in facility-limited settings.
