The Experts below are selected from a list of 177 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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artificial photosynthesis where are we now where can we go
Journal of Photochemistry and Photobiology C-photochemistry Reviews, 2015Co-Authors: Ralph L House, Neyde Yukie Murakami Iha, Rodolfo L Coppo, Leila Alibabaei, Benjamin D Sherman, Peng Kang, Kyle M Brennaman, Paul G Hoertz, Thomas J MeyerAbstract:Abstract Widespread implementation of renewable energy technologies, while preventing significant increases in greenhouse gas emissions, appears to be the only viable solution to meeting the world's energy demands for a sustainable energy future. The final energy mix will include conservation and energy efficiency, wind, geothermal, biomass, and others, but none more ubiquitous or abundant than the sun. Over several decades of development, the cost of photovoltaic cells has decreased significantly with lifetimes that exceed 25 years and there is promise for widespread implementation in the future. However, the solar input is intermittent and, to be practical at a truly large scale, will require an equally large capability for energy storage. One approach involves artificial photosynthesis and the use of the sun to drive solar fuel reactions for water splitting into hydrogen and oxygen or to reduce CO2 to reduced carbon fuels. An early breakthrough in this area came from an initial report by Honda and Fujishima on photoelectrochemical water splitting at TiO2 with UV excitation. Significant progress has been made since in exploiting semiconductor devices in water splitting with impressive gains in spectral coverage and solar efficiencies. An alternate, hybrid approach, which integrates molecular light absorption and catalysis with the band gap properties of oxide semiconductors, the dye-sensitized photoelectrosynthesis cell (DSPEC), has been pioneered by the University of North Carolina Energy Frontier Research Center (UNC EFRC) on Solar Fuels. By utilizing chromophore-catalyst assemblies, core/shell oxide structures, and surface stabilization, the EFRC recently demonstrated a viable DSPEC for solar water splitting.
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chemical approaches to artificial photosynthesis
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Javier J Concepcion, Ralph L House, John M Papanikolas, Thomas J MeyerAbstract:In the early 1970s, the works by Fujishima and Honda (1) and Honda et al. (2) reported on the results of a now famous experiment. They showed that band gap excitation of anatase TiO2 in a photoelectrochemical cell with a Pt counter electrode and an applied bias resulted in water splitting into hydrogen and oxygen. The timing of the result was impeccable. In 1973, the Organization of the Petroleum Exporting Countries (OPEC) declared an embargo on oil imports to the West, resulting in gasoline shortages and long lines at gas pumps. Suddenly, there was a pressing need for energy independence and new ways of providing for the energy-hungry economies of Western Europe, Japan, and the United States. The international research community responded. There was a short lived explosion of interest in converting sunlight into high-energy molecules by what we now call artificial photosynthesis to make solar fuels. Target reactions were water splitting into hydrogen and oxygen (1) and light-driven reduction of CO2 by water to give CO, other oxygenates, or hydrocarbons. Methane is shown as the product in equation 2, but the ultimate target is liquid hydrocarbons to power our existing energy infrastructure (1 and 2):
Ryu Abe - One of the best experts on this subject based on the ideXlab platform.
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recent progress on photocatalytic and photoelectrochemical water splitting under visible light irradiation
Journal of Photochemistry and Photobiology C-photochemistry Reviews, 2010Co-Authors: Ryu AbeAbstract:Abstract Photocatalytic and photoelectrochemical (PEC) water splitting using semiconductor materials has attracted considerable interest due to its potential to cleanly produce H 2 from water by utilizing abundant solar light. Since Fujishima and Honda used a TiO 2 photoanode in 1972 to split water, researchers have been attempting to develop water-splitting systems that can efficiently use visible light (which accounts for almost half of the solar spectrum on the Earth's surface) in order to realize efficient conversion of solar light. In this report, we review recent progress in this field by focusing on strategies that utilize visible light. Such strategies include two-step photoexcitation systems that were inspired by photosynthesis in nature, band engineering for producing novel photocatalysts that have both a high visible light absorption and suitable energy levels for water splitting, the development of new cocatalysts for efficient H 2 or O 2 production, fabrication of efficient photoelectrodes based on visible-light-responsive semiconductors, and the construction of tandem-type PEC water-splitting systems.
Ralph L House - One of the best experts on this subject based on the ideXlab platform.
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artificial photosynthesis where are we now where can we go
Journal of Photochemistry and Photobiology C-photochemistry Reviews, 2015Co-Authors: Ralph L House, Neyde Yukie Murakami Iha, Rodolfo L Coppo, Leila Alibabaei, Benjamin D Sherman, Peng Kang, Kyle M Brennaman, Paul G Hoertz, Thomas J MeyerAbstract:Abstract Widespread implementation of renewable energy technologies, while preventing significant increases in greenhouse gas emissions, appears to be the only viable solution to meeting the world's energy demands for a sustainable energy future. The final energy mix will include conservation and energy efficiency, wind, geothermal, biomass, and others, but none more ubiquitous or abundant than the sun. Over several decades of development, the cost of photovoltaic cells has decreased significantly with lifetimes that exceed 25 years and there is promise for widespread implementation in the future. However, the solar input is intermittent and, to be practical at a truly large scale, will require an equally large capability for energy storage. One approach involves artificial photosynthesis and the use of the sun to drive solar fuel reactions for water splitting into hydrogen and oxygen or to reduce CO2 to reduced carbon fuels. An early breakthrough in this area came from an initial report by Honda and Fujishima on photoelectrochemical water splitting at TiO2 with UV excitation. Significant progress has been made since in exploiting semiconductor devices in water splitting with impressive gains in spectral coverage and solar efficiencies. An alternate, hybrid approach, which integrates molecular light absorption and catalysis with the band gap properties of oxide semiconductors, the dye-sensitized photoelectrosynthesis cell (DSPEC), has been pioneered by the University of North Carolina Energy Frontier Research Center (UNC EFRC) on Solar Fuels. By utilizing chromophore-catalyst assemblies, core/shell oxide structures, and surface stabilization, the EFRC recently demonstrated a viable DSPEC for solar water splitting.
-
chemical approaches to artificial photosynthesis
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Javier J Concepcion, Ralph L House, John M Papanikolas, Thomas J MeyerAbstract:In the early 1970s, the works by Fujishima and Honda (1) and Honda et al. (2) reported on the results of a now famous experiment. They showed that band gap excitation of anatase TiO2 in a photoelectrochemical cell with a Pt counter electrode and an applied bias resulted in water splitting into hydrogen and oxygen. The timing of the result was impeccable. In 1973, the Organization of the Petroleum Exporting Countries (OPEC) declared an embargo on oil imports to the West, resulting in gasoline shortages and long lines at gas pumps. Suddenly, there was a pressing need for energy independence and new ways of providing for the energy-hungry economies of Western Europe, Japan, and the United States. The international research community responded. There was a short lived explosion of interest in converting sunlight into high-energy molecules by what we now call artificial photosynthesis to make solar fuels. Target reactions were water splitting into hydrogen and oxygen (1) and light-driven reduction of CO2 by water to give CO, other oxygenates, or hydrocarbons. Methane is shown as the product in equation 2, but the ultimate target is liquid hydrocarbons to power our existing energy infrastructure (1 and 2):
Suresh C Pillai - One of the best experts on this subject based on the ideXlab platform.
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visible light activation of tio2 photocatalysts advances in theory and experiments
Journal of Photochemistry and Photobiology C-photochemistry Reviews, 2015Co-Authors: Vinodkumar Etacheri, Cristiana Di Valentin, Jenny Schneider, Detlef W Bahnemann, Suresh C PillaiAbstract:Abstract The remarkable achievement by Fujishima and Honda (1972) in the photo-electrochemical water splitting results in the extensive use of TiO 2 nanomaterials for environmental purification and energy storage/conversion applications. Though there are many advantages for the TiO 2 compared to other semiconductor photocatalysts, its band gap of 3.2 eV restrains application to the UV-region of the electromagnetic spectrum ( λ ≤ 387.5 nm). As a result, development of visible-light active titanium dioxide is one of the key challenges in the field of semiconductor photocatalysis. In this review, advances in the strategies for the visible light activation, origin of visible-light activity, and electronic structure of various visible-light active TiO 2 photocatalysts are discussed in detail. It has also been shown that if appropriate models are used, the theoretical insights can successfully be employed to develop novel catalysts to enhance the photocatalytic performance in the visible region. Recent developments in theory and experiments in visible-light induced water splitting, degradation of environmental pollutants, water and air purification and antibacterial applications are also reviewed. Various strategies to identify appropriate dopants for improved visible-light absorption and electron–hole separation to enhance the photocatalytic activity are discussed in detail, and a number of recommendations are also presented.
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a review on the visible light active titanium dioxide photocatalysts for environmental applications
Applied Catalysis B-environmental, 2012Co-Authors: Miguel Pelaez, Suresh C Pillai, Nicholas T Nolan, Michael K Seery, Polycarpos Falaras, Athanassios G Kontos, P S M Dunlop, Jeremy W J Hamilton, Anthony J Byrne, Kevin E OsheaAbstract:Fujishima and Honda (1972) demonstrated the potential of titanium dioxide (TiO2) semiconductor materials to split water into hydrogen and oxygen in a photo-electrochemical cell. Their work triggered the development of semiconductor photocatalysis for a wide range of environmental and energy applications. One of the most significant scientific and commercial advances to date has been the development of visible light active (VLA) TiO2 photocatalytic materials. In this review, a background on TiO2 structure, properties and electronic properties in photocatalysis is presented. The development of different strategies to modify TiO2 for the utilization of visible light, including non metal and/or metal doping, dye sensitization and coupling semiconductors are discussed. Emphasis is given to the origin of visible light absorption and the reactive oxygen species generated, deduced by physicochemical and photoelectrochemical methods. Various applications of VLA TiO2, in terms of environmental remediation and in particular water treatment, disinfection and air purification, are illustrated. Comprehensive studies on the photocatalytic degradation of contaminants of emerging concern, including endocrine disrupting compounds, pharmaceuticals, pesticides, cyanotoxins and volatile organic compounds, with VLA TiO2 are discussed and compared to conventional UV-activated TiO2 nanomaterials. Recent advances in bacterial disinfection using VLA TiO2 are also reviewed. Issues concerning test protocols for real visible light activity and photocatalytic efficiencies with different light sources have been highlighted.
Lingyu Piao - One of the best experts on this subject based on the ideXlab platform.
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recent progress for hydrogen production by photocatalytic natural or simulated seawater splitting
Nano Research, 2020Co-Authors: Jining Zhang, Shuang Cao, Lingyu PiaoAbstract:Solar energy is an inexhaustible renewable energy source. Among the various methods for solar energy conversion, photocatalytic hydrogen (H2) production is considered as one of the most promising ways. Since Fujishima pioneered this field in 1972, photocatalytic water splitting to produce H2 has received widespread attention. Up to now, abundant semiconductor materials have been explored as photocatalysts for pure water splitting to produce H2. However, photocatalytic seawater splitting is more in line with the concept of sustainable development, which can greatly alleviate the problem of limited freshwater resource. At present, only few studies have focused on the process of H2 production by photocatalytic seawater splitting due to the complex composition of seawater and lack of suitable photocatalysts. In this review, we outline the most recent advances in photocatalytic seawater splitting. In particular, we introduce the H2 production photocatalysts, underlying mechanism of ions in seawater on photocatalytic seawater splitting, current challenges and future potential advances for this exciting field.
