The Experts below are selected from a list of 6177 Experts worldwide ranked by ideXlab platform
Thomas J Meyer - One of the best experts on this subject based on the ideXlab platform.
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dye sensitized hydrobromic acid splitting for hydrogen Solar Fuel production
Journal of the American Chemical Society, 2017Co-Authors: Matthew D Brady, Renato N Sampaio, Degao Wang, Thomas J Meyer, Gerald J MeyerAbstract:Hydrobromic acid (HBr) has significant potential as an inexpensive feedstock for hydrogen gas (H2) Solar Fuel production through HBr splitting. Mesoporous thin films of anatase TiO2 or SnO2/TiO2 core–shell nanoparticles were sensitized to visible light with a new RuII polypyridyl complex that served as a photocatalyst for bromide oxidation. These thin films were tested as photoelectrodes in dye-sensitized photoelectrosynthesis cells. In 1 N HBr (aq), the photocatalyst undergoes excited-state electron injection and light-driven Br– oxidation. The injected electrons induce proton reduction at a Pt electrode. Under 100 mW cm−2 white-light illumination, sustained photocurrents of 1.5 mA cm–2 were measured under an applied bias. Faradaic efficiencies of 71 ± 5% for Br– oxidation and 94 ± 2% for H2 production were measured. A 12 μmol h–1 sustained rate of H2 production was maintained during illumination. The results demonstrate a molecular approach to HBr splitting with a visible light absorbing complex capable...
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molecular chromophore catalyst assemblies for Solar Fuel applications
Chemical Reviews, 2015Co-Authors: Dennis L. Ashford, Melissa K Gish, Aaron K Vannucci, Kyle M Brennaman, Joseph L Templeton, John M Papanikolas, Thomas J MeyerAbstract:Applications Dennis L. Ashford,† Melissa K. Gish,† Aaron K. Vannucci,‡ M. Kyle Brennaman,† Joseph L. Templeton,† John M. Papanikolas,† and Thomas J. Meyer*,† †Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Chapel Hill, North Carolina 27599, United States ‡Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
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Applications of metal oxide materials in dye sensitized photoelectrosynthesis cells for making Solar Fuels: let the molecules do the work
Journal of Materials Chemistry, 2013Co-Authors: Leila Alibabaei, Ralph L. House, Paul G. Hoertz, Rene Lopez, Thomas J MeyerAbstract:Solar Fuels hold great promise as a permanent, environmentally friendly, long-term renewable energy source, that would be readily available across the globe. In this account, an approach to Solar Fuels is described based on Dye Sensitized Photoelectrosynthesis Cells (DSPEC) that mimic the configuration used in Dye Sensitized Solar Cells (DSSC), but with the goal of producing oxygen and a high energy Solar Fuel in the separate compartments of a photoelectrochemical cell rather than a photopotential and photocurrent.
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Interfacial dynamics and Solar Fuel formation in dye-sensitized photoelectrosynthesis cells.
ChemPhysChem, 2012Co-Authors: Wenjing Song, Zuofeng Chen, Christopher R. K. Glasson, Kenneth Hanson, Michael R. Norris, Dennis L. Ashford, Javier J. Concepcion, M. Kyle Brennaman, Thomas J MeyerAbstract:Dye-sensitized photoelectrosynthesis cells (DSPECs) represent a promising approach to Solar Fuels with Solar-energy storage in chemical bonds. The targets are water splitting and carbon dioxide reduction by water to CO, other oxygenates, or hydrocarbons. DSPECs are based on dye-sensitized Solar cells (DSSCs) but with photoexcitation driving physically separated Solar Fuel half reactions. A systematic basis for DSPECs is available based on a modular approach with light absorption/excited-state electron injection, and catalyst activation assembled in integrated structures. Progress has been made on catalysts for water oxidation and CO2 reduction, dynamics of electron injection, back electron transfer, and photostability under conditions appropriate for water splitting. With added reductive scavengers, as surrogates for water oxidation, DSPECs have been investigated for hydrogen generation based on transient absorption and photocurrent measurements. Detailed insights are emerging which define kinetic and thermodynamic requirements for the individual processes underlying DSPEC performance.
James Barber - One of the best experts on this subject based on the ideXlab platform.
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iron based photoanodes for Solar Fuel production
Physical Chemistry Chemical Physics, 2014Co-Authors: Prince Saurabh Bassi, Lydia Helena Wong, James BarberAbstract:In natural photosynthesis, the water splitting reaction of photosystem II is the source of the electrons/reducing equivalents for the reduction of carbon dioxide to carbohydrate while oxygen is formed as the by-product. Similarly, for artificial photosynthesis where the end product is a Solar Fuel such as hydrogen, a water splitting-oxygen evolving system is required to supply high energy electrons to drive the reductive reactions. Very attractive candidates for this purpose are iron based semiconductors which have band gaps corresponding to visible light and valence band energies sufficient to oxidise water. The most studied system is hematite (Fe2O3) which is highly abundant with many attributes for incorporation into photoelectrochemical (PEC) cells. We review the recent progress in manipulating hematite for this purpose through nanostructuring, doping and surface modifications. We also consider several hybrid iron-based semiconducting systems like ferrites and iron titanates as alternatives to hematite for light driven water splitting emphasizing their advantages with respect to their band levels and charge transport properties.
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recent advances in hybrid photocatalysts for Solar Fuel production
Energy and Environmental Science, 2012Co-Authors: Phong D Tran, Lydia Helena Wong, James BarberAbstract:Converting Solar energy into Fuel via photo-assisted water splitting to generate hydrogen or drive CO2 reduction is an attractive scientific and technological goal to address the increasing global demand for energy and to reduce the impact of energy production on climate change. Engineering an efficient, low-cost photocatalyst is necessary to achieve this technological goal. A photocatalyst combines a photosensitiser and an electrocatalyst to capture light and accelerate the chemical reactions in the same device. In this perspective paper, we first describe the recent developments of some families of semiconductors that are attractive candidates for engineering photocatalysts. We then discuss the use of semiconductors as light harvesting agents, combined with a bio-catalyst, synthetic bio-mimetic molecular catalyst or synthetic all-inorganic catalyst, in photocatalytic hybrid systems for water splitting and CO2 reduction. To highlight the advantages of semiconductors for engineering efficient and robust photocatalysts, we compare these systems to examples of homogeneous photocatalytic systems constructed from molecular photosensitisers (dyes). We conclude that all-inorganic catalysts coupled to appropriate semiconductors look more promising for the construction of robust photocatalytic hybrid systems for producing Solar Fuels.
Yiying Wu - One of the best experts on this subject based on the ideXlab platform.
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membrane inspired acidically stable dye sensitized photocathode for Solar Fuel production
Journal of the American Chemical Society, 2016Co-Authors: Kevin A. Click, Damian R. Beauchamp, Zhongjie Huang, Weilin Chen, Yiying WuAbstract:Tandem dye-sensitized photoelectrochemical cells (DSPECs) for water splitting are a promising method for sustainable energy conversion but so far have been limited by their lack of aqueous stability and photocurrent mismatch between the cathode and anode. In nature, membrane-enabled subcellular compartmentation is a general approach to control local chemical environments in the cell. The hydrophobic tails of the lipid make the bilayer impermeable to ions and hydrophilic molecules. Herein we report the use of an organic donor–acceptor dye that prevents both dye desorption and semiconductor degradation by mimicking the hydrophobic/hydrophilic properties of lipid bilayer membranes. The dual-functional photosensitizer (denoted as BH4) allows for efficient light harvesting while also protecting the semiconductor surface from protons and water via its hydrophobic π linker. The protection afforded by this membrane-mimicking dye gives this system excellent stability in extremely acidic (pH 0) conditions. The acid...
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Membrane-Inspired Acidically Stable Dye-Sensitized Photocathode for Solar Fuel Production
Journal of the American Chemical Society, 2016Co-Authors: Kevin A. Click, Damian R. Beauchamp, Zhongjie Huang, Weilin Chen, Yiying WuAbstract:Tandem dye-sensitized photoelectrochemical cells (DSPECs) for water splitting are a promising method for sustainable energy conversion but so far have been limited by their lack of aqueous stability and photocurrent mismatch between the cathode and anode. In nature, membrane-enabled subcellular compartmentation is a general approach to control local chemical environments in the cell. The hydrophobic tails of the lipid make the bilayer impermeable to ions and hydrophilic molecules. Herein we report the use of an organic donor-acceptor dye that prevents both dye desorption and semiconductor degradation by mimicking the hydrophobic/hydrophilic properties of lipid bilayer membranes. The dual-functional photosensitizer (denoted as BH4) allows for efficient light harvesting while also protecting the semiconductor surface from protons and water via its hydrophobic π-linker. The protection afforded by this membrane-mimicking dye gives this system excellent stability in extremely acidic (pH = 0) conditions. The acidic stability also allows for the use of cubane molybdenum-sulfide cluster as the hydrogen evolution reaction (HER) catalyst. This system produces a proton-reducing current of 183 ± 36 μA/cm2 (0 V vs NHE with 300 W Xe lamp) for an unprecedented 16 hours with no degradation. These results introduce a method for developing high-current, low-pH DSPECs and are a significant move toward practical dye-sensitized Solar Fuel production.
Kevin A. Click - One of the best experts on this subject based on the ideXlab platform.
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membrane inspired acidically stable dye sensitized photocathode for Solar Fuel production
Journal of the American Chemical Society, 2016Co-Authors: Kevin A. Click, Damian R. Beauchamp, Zhongjie Huang, Weilin Chen, Yiying WuAbstract:Tandem dye-sensitized photoelectrochemical cells (DSPECs) for water splitting are a promising method for sustainable energy conversion but so far have been limited by their lack of aqueous stability and photocurrent mismatch between the cathode and anode. In nature, membrane-enabled subcellular compartmentation is a general approach to control local chemical environments in the cell. The hydrophobic tails of the lipid make the bilayer impermeable to ions and hydrophilic molecules. Herein we report the use of an organic donor–acceptor dye that prevents both dye desorption and semiconductor degradation by mimicking the hydrophobic/hydrophilic properties of lipid bilayer membranes. The dual-functional photosensitizer (denoted as BH4) allows for efficient light harvesting while also protecting the semiconductor surface from protons and water via its hydrophobic π linker. The protection afforded by this membrane-mimicking dye gives this system excellent stability in extremely acidic (pH 0) conditions. The acid...
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Membrane-Inspired Acidically Stable Dye-Sensitized Photocathode for Solar Fuel Production
Journal of the American Chemical Society, 2016Co-Authors: Kevin A. Click, Damian R. Beauchamp, Zhongjie Huang, Weilin Chen, Yiying WuAbstract:Tandem dye-sensitized photoelectrochemical cells (DSPECs) for water splitting are a promising method for sustainable energy conversion but so far have been limited by their lack of aqueous stability and photocurrent mismatch between the cathode and anode. In nature, membrane-enabled subcellular compartmentation is a general approach to control local chemical environments in the cell. The hydrophobic tails of the lipid make the bilayer impermeable to ions and hydrophilic molecules. Herein we report the use of an organic donor-acceptor dye that prevents both dye desorption and semiconductor degradation by mimicking the hydrophobic/hydrophilic properties of lipid bilayer membranes. The dual-functional photosensitizer (denoted as BH4) allows for efficient light harvesting while also protecting the semiconductor surface from protons and water via its hydrophobic π-linker. The protection afforded by this membrane-mimicking dye gives this system excellent stability in extremely acidic (pH = 0) conditions. The acidic stability also allows for the use of cubane molybdenum-sulfide cluster as the hydrogen evolution reaction (HER) catalyst. This system produces a proton-reducing current of 183 ± 36 μA/cm2 (0 V vs NHE with 300 W Xe lamp) for an unprecedented 16 hours with no degradation. These results introduce a method for developing high-current, low-pH DSPECs and are a significant move toward practical dye-sensitized Solar Fuel production.
Andrew B Bocarsly - One of the best experts on this subject based on the ideXlab platform.
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photons to formate efficient electrochemical Solar energy conversion via reduction of carbon dioxide
Journal of CO 2 Utilization, 2014Co-Authors: James L. White, Jake T. Herb, Jerry J. Kaczur, Paul W. Majsztrik, Andrew B BocarslyAbstract:Abstract The storage of Solar energy as formic acid generated electrochemically from carbon dioxide has been identified as a viable Solar Fuel pathway. We report that this transformation can be accomplished by separating light absorption and CO 2 reduction through the use of a commercial Solar panel illuminated with natural AM1.5 sunlight to power a custom closed-loop electrochemical flow cell stack. Faradaic yields for formate of up to 67% have been demonstrated in this system, yielding a Solar energy to Fuel thermionic conversion efficiency above 1.8%.
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Photons to formate: Efficient electrochemical Solar energy conversion via reduction of carbon dioxide
Journal of CO2 Utilization, 2014Co-Authors: James L. White, Jake T. Herb, Jerry J. Kaczur, Paul W. Majsztrik, Andrew B BocarslyAbstract:The storage of Solar energy as formic acid generated electrochemically from carbon dioxide has been identified as a viable Solar Fuel pathway. We report that this transformation can be accomplished by separating light absorption and CO2 reduction through the use of a commercial Solar panel illuminated with natural AM1.5 sunlight to power a custom closed-loop electrochemical flow cell stack. Faradaic yields for formate of up to 67% have been demonstrated in this system, yielding a Solar energy to Fuel thermionic conversion efficiency above 1.8%. © 2014 Elsevier Ltd.
