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Kazunari Domen - One of the best experts on this subject based on the ideXlab platform.
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Recent developments in heterogeneous photocatalysts for solar-driven Overall Water Splitting
Chemical Society Reviews, 2019Co-Authors: Zheng Wang, Kazunari DomenAbstract:Overall Water Splitting based on particulate photocatalysts is an easily constructed and cost-effective technology for the conversion of abundant solar energy into clean and renewable hydrogen energy on a large scale. This promising technology can be achieved in a one-step excitation system using a single photocatalyst or via a Z-scheme process based on a pair of photocatalysts. Ideally, such photocatalysis will proceed with charge separation and transport unaffected by recombination and trapping, and surface catalytic processes will not involve undesirable reactions. This review summarizes the basics of Overall Water Splitting via both one-step excitation and Z-scheme processes, with a focus on standard methods of determining photocatalytic performance. Various surface engineering strategies applied to photocatalysts, such as cocatalyst loading, surface morphology control, surface modification and surface phase junctions, have been developed to allow efficient one-step excitation Overall Water Splitting. In addition, numerous visible-light-responsive photocatalysts have been successfully utilized as H2-evolution or O2-evolution photocatalysts in Z-scheme Overall Water Splitting. Prototype particulate immobilization systems with photocatalytic performances comparable to or drastically higher than those of particle suspension systems suggest the exciting possibility of the large-scale production of low-cost renewable solar hydrogen.
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Particulate photocatalysts for Overall Water Splitting
Nature Reviews Materials, 2017Co-Authors: Shanshan Chen, Tsuyoshi Takata, Kazunari DomenAbstract:Overall Water Splitting using powdered photocatalysts is a promising approach to large-scale solar hydrogen production. This Review details recent developments in particulate photocatalysts for Overall Water Splitting based on one- and two-step photoexcitation systems. The conversion of solar energy to chemical energy is a promising way of generating renewable energy. Hydrogen production by means of Water Splitting over semiconductor photocatalysts is a simple, cost-effective approach to large-scale solar hydrogen synthesis. Since the discovery of the Honda–Fujishima effect, considerable progress has been made in this field, and numerous photocatalytic materials and Water-Splitting systems have been developed. In this Review, we summarize existing Water-Splitting systems based on particulate photocatalysts, focusing on the main components: light-harvesting semiconductors and co-catalysts. The essential design principles of the materials employed for Overall Water-Splitting systems based on one-step and two-step photoexcitation are also discussed, concentrating on three elementary processes: photoabsorption, charge transfer and surface catalytic reactions. Finally, we outline challenges and potential advances associated with solar Water Splitting by particulate photocatalysts for future commercial applications.
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particulate photocatalysts for Overall Water Splitting
Nature Reviews Materials, 2017Co-Authors: Shanshan Chen, Tsuyoshi Takata, Kazunari DomenAbstract:Overall Water Splitting using powdered photocatalysts is a promising approach to large-scale solar hydrogen production. This Review details recent developments in particulate photocatalysts for Overall Water Splitting based on one- and two-step photoexcitation systems.
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Toward Visible Light Response: Overall Water Splitting Using Heterogeneous Photocatalysts
Green, 2011Co-Authors: Kazuhiro Takanabe, Kazunari DomenAbstract:AbstractExtensive energy conversion of solar energy can only be achieved by large-scale collection of solar flux. The technology that satisfies this requirement must be as simple as possible to reduce capital cost. Overall Water Splitting by powder-form photocatalysts directly produces a mixture of H
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Recent progress in photocatalysts for Overall Water Splitting under visible light
Solar Hydrogen and Nanotechnology IV, 2009Co-Authors: Takashi Hisatomi, Kazunari DomenAbstract:Photocatalytic Overall Water Splitting promises to enable a sustainable large-scale hydrogen-based energy system using solar light, and great attention has been paid to the development of photocatalysts. It is necessary to develop photocatalysts that function under visible light to utilize sunlight efficiently. We have proposed non-oxide materials as candidates for visible-light-driven photocatalysts for Overall Water Splitting, and this manuscript presents our recent research in photocatalyst development. Some oxynitride photocatalysts, modified with appropriate cocatalysts, showed performance for Overall Water Splitting under visible light irradiation. The modification with cocatalysts drastically improved the efficiency of photocatalytic reactions, indicating the importance of controlling the surface active sites. Two-step excitation systems, known as Z-schemes, can significantly expand the range of light available for Water Splitting to longer wavelengths.
Tsuyoshi Takata - One of the best experts on this subject based on the ideXlab platform.
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particulate photocatalysts for Overall Water Splitting
Nature Reviews Materials, 2017Co-Authors: Shanshan Chen, Tsuyoshi Takata, Kazunari DomenAbstract:Overall Water Splitting using powdered photocatalysts is a promising approach to large-scale solar hydrogen production. This Review details recent developments in particulate photocatalysts for Overall Water Splitting based on one- and two-step photoexcitation systems.
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Particulate photocatalysts for Overall Water Splitting
Nature Reviews Materials, 2017Co-Authors: Shanshan Chen, Tsuyoshi Takata, Kazunari DomenAbstract:Overall Water Splitting using powdered photocatalysts is a promising approach to large-scale solar hydrogen production. This Review details recent developments in particulate photocatalysts for Overall Water Splitting based on one- and two-step photoexcitation systems. The conversion of solar energy to chemical energy is a promising way of generating renewable energy. Hydrogen production by means of Water Splitting over semiconductor photocatalysts is a simple, cost-effective approach to large-scale solar hydrogen synthesis. Since the discovery of the Honda–Fujishima effect, considerable progress has been made in this field, and numerous photocatalytic materials and Water-Splitting systems have been developed. In this Review, we summarize existing Water-Splitting systems based on particulate photocatalysts, focusing on the main components: light-harvesting semiconductors and co-catalysts. The essential design principles of the materials employed for Overall Water-Splitting systems based on one-step and two-step photoexcitation are also discussed, concentrating on three elementary processes: photoabsorption, charge transfer and surface catalytic reactions. Finally, we outline challenges and potential advances associated with solar Water Splitting by particulate photocatalysts for future commercial applications.
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z scheme Overall Water Splitting on modified taon photocatalysts under visible light λ 500 nm
Chemistry Letters, 2008Co-Authors: Masanobu Higashi, Tsuyoshi Takata, Ryu Abe, Akio Ishikawa, Bunsho Ohtani, Kazunari DomenAbstract:Overall Water Splitting was accomplished using a RuO2–TaON and Pt–TaON mixture with IO3−/I− redox couple under visible light (λ<500 nm). This is the first example of Overall Water Splitting based o...
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Z-scheme Overall Water Splitting on Modified-TaON Photocatalysts under Visible Light (λ
Chemistry Letters, 2008Co-Authors: Masanobu Higashi, Tsuyoshi Takata, Ryu Abe, Akio Ishikawa, Bunsho Ohtani, Kazunari DomenAbstract:Overall Water Splitting was accomplished using a RuO2–TaON and Pt–TaON mixture with IO3−/I− redox couple under visible light (λ
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gan zno solid solution as a photocatalyst for visible light driven Overall Water Splitting
Journal of the American Chemical Society, 2005Co-Authors: Kazuhiko Maeda, Tsuyoshi Takata, Michikazu Hara, Nobuo Saito, Yasunobu Inoue, Hisayoshi Kobayashi, Kazunari DomenAbstract:Photocatalytic Overall Water Splitting has been studied extensively from the viewpoint of solar energy conversion. Despite numerous attempts, none have yielded satisfactory results for the development of photocatalysts, which work under visible light irradiation to efficiently utilize solar energy. We report here the first example of visible-light-driven Overall Water Splitting on a novel oxynitride photocatalyst, a solid solution of GaN and ZnO with a band gap of 2.58−2.76 eV, modified with RuO2 nanoparticles. In contrast to the conventional non-oxide photocatalysts, such as CdS, the solid solution is stable during the Overall Water Splitting reaction. This is the first example of achieving Overall Water Splitting by a photocatalyst with a band gap in the visible light region, which opens the possibility of new non-oxide-type photocatalysts for energy conversion.
Jicai Feng - One of the best experts on this subject based on the ideXlab platform.
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Bifunctional Electrocatalysts Based on Mo-Doped NiCoP Nanosheet Arrays for Overall Water Splitting
Nano-Micro Letters, 2019Co-Authors: Jinghuang Lin, Yaotian Yan, Jian Cao, Haohan Wang, Zhengxiang Zhong, Weidong Fei, Jicai FengAbstract:Rational design of efficient bifunctional electrocatalysts is highly imperative but still a challenge for Overall Water Splitting. Herein, we construct novel freestanding Mo-doped NiCoP nanosheet arrays by the hydrothermal and phosphation processes, serving as bifunctional electrocatalysts for Overall Water Splitting. Notably, Mo doping could effectively modulate the electronic structure of NiCoP, leading to the increased electroactive site and improved intrinsic activity of each site. Furthermore, an electrochemical activation strategy is proposed to form Mo-doped (Ni,Co)OOH to fully boost the electrocatalytic activities for oxygen evolution reaction. Benefiting from the unique freestanding structure and Mo doping, Mo-doped NiCoP and (Ni,Co)OOH show the remarkable electrochemical performances, which are competitive among current researches. In addition, an Overall Water Splitting device assembled by both electrodes only requires a cell voltage of 1.61 V to reach a current density of 10 mA cm−2. Therefore, this work opens up new avenues for designing nonprecious bifunctional electrocatalysts by Mo doping and in situ electrochemical activation.
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defect rich heterogeneous mos2 nis2 nanosheets electrocatalysts for efficient Overall Water Splitting
Advanced Science, 2019Co-Authors: Jinghuang Lin, Jian Cao, Pengcheng Wang, Haohan Wang, Zhengxiang Zhong, W D Fei, Jicai FengAbstract:Designing and constructing bifunctional electrocatalysts is vital for Water Splitting. Particularly, the rational interface engineering can effectively modify the active sites and promote the electronic transfer, leading to the improved Splitting efficiency. Herein, free-standing and defect-rich heterogeneous MoS2/NiS2 nanosheets for Overall Water Splitting are designed. The abundant heterogeneous interfaces in MoS2/NiS2 can not only provide rich electroactive sites but also facilitate the electron transfer, which further cooperate synergistically toward electrocatalytic reactions. Consequently, the optimal MoS2/NiS2 nanosheets show the enhanced electrocatalytic performances as bifunctional electrocatalysts for Overall Water Splitting. This study may open up a new route for rationally constructing heterogeneous interfaces to maximize their electrochemical performances, which may help to accelerate the development of nonprecious electrocatalysts for Overall Water Splitting.
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Defect-Rich Heterogeneous MoS2/NiS2 Nanosheets Electrocatalysts for Efficient Overall Water Splitting.
Advanced Science, 2019Co-Authors: Jinghuang Lin, Jian Cao, Pengcheng Wang, Haohan Wang, Zhengxiang Zhong, Weidong Fei, Jicai FengAbstract:Designing and constructing bifunctional electrocatalysts is vital for Water Splitting. Particularly, the rational interface engineering can effectively modify the active sites and promote the electronic transfer, leading to the improved Splitting efficiency. Herein, free-standing and defect-rich heterogeneous MoS2/NiS2 nanosheets for Overall Water Splitting are designed. The abundant heterogeneous interfaces in MoS2/NiS2 can not only provide rich electroactive sites but also facilitate the electron transfer, which further cooperate synergistically toward electrocatalytic reactions. Consequently, the optimal MoS2/NiS2 nanosheets show the enhanced electrocatalytic performances as bifunctional electrocatalysts for Overall Water Splitting. This study may open up a new route for rationally constructing heterogeneous interfaces to maximize their electrochemical performances, which may help to accelerate the development of nonprecious electrocatalysts for Overall Water Splitting.
Michikazu Hara - One of the best experts on this subject based on the ideXlab platform.
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gan zno solid solution as a photocatalyst for visible light driven Overall Water Splitting
Journal of the American Chemical Society, 2005Co-Authors: Kazuhiko Maeda, Tsuyoshi Takata, Michikazu Hara, Nobuo Saito, Yasunobu Inoue, Hisayoshi Kobayashi, Kazunari DomenAbstract:Photocatalytic Overall Water Splitting has been studied extensively from the viewpoint of solar energy conversion. Despite numerous attempts, none have yielded satisfactory results for the development of photocatalysts, which work under visible light irradiation to efficiently utilize solar energy. We report here the first example of visible-light-driven Overall Water Splitting on a novel oxynitride photocatalyst, a solid solution of GaN and ZnO with a band gap of 2.58−2.76 eV, modified with RuO2 nanoparticles. In contrast to the conventional non-oxide photocatalysts, such as CdS, the solid solution is stable during the Overall Water Splitting reaction. This is the first example of achieving Overall Water Splitting by a photocatalyst with a band gap in the visible light region, which opens the possibility of new non-oxide-type photocatalysts for energy conversion.
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Mechano-catalytic Overall Water Splitting on some mixed oxides
Catalysis Today, 2000Co-Authors: Go Hitoki, Michikazu Hara, Tsuyosi Takata, Shigeru Ikeda, Junko N. Kondo, Masato Kakihana, Kazunari DomenAbstract:Abstract Simple transition metal oxides such as NiO, Co3O4, Fe3O4 and Cu2O were found to catalytically decompose Water into H2 and O2 by mechanical energy. The reaction is regarded as “mechano-catalytic” Overall Water Splitting” and is a quite novel catalytic reaction. In this paper, some general aspects on the mechano-catalytic Overall Water Splitting are reviewed on simple oxides. In addition, recent results on the mechano-catalytic activity of a groups of mixed oxides, wolramite-type oxides with a formula of ABO4 (A=Fe, Co, Ni and Cu, etc., B=W, Mo), are shown. AWO4 (A=Fe, Co, Ni and Cu) decomposed Water into H2 and O2 under the supply of mechanical energy, indicating that mechano-catalytic Overall Water Splitting proceeded on wolframite-type compounds containing 3d-transition metals. AMoO4 (A=Fe, Co, Ni) also decomposed Water into H2 and O2 under supply of mechanical energy. The reaction properties on wolframite-type oxides are discussed.
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photo and mechano catalytic Overall Water Splitting reactions to form hydrogen and oxygen on heterogeneous catalysts
Bulletin of the Chemical Society of Japan, 2000Co-Authors: Kazunari Domen, Michikazu Hara, Junko N. Kondo, Tsuyoshi TakataAbstract:Recent progress of Overall Water Splitting by photocatalysts and mechanocatalysts is briefly reviewed. In photocatalytic reactions, several new materials have been introduced, and the catalyst preparation has also been improved. As a result, a high quantum efficiency for Overall Water Splitting of about 30% has been accomplished. In addition, recent progress in the understanding of the reaction mechanism is briefly introduced. On the other hand, mechano-catalytic Overall Water Splitting reaction has been recently discovered by the authors. The phenomenological aspects of this novel reaction are summarized, and some implications of the reaction mechanism are also described.
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A Study of Mechano-Catalysts for Overall Water Splitting
The Journal of Physical Chemistry B, 2000Co-Authors: Michikazu Hara, Tsuyoshi Takata, Mutsuko Komoda, Hironori Hasei, Masaaki Yashima, Sigeru Ikeda, And Junko N. Kondo, Kazunari DomenAbstract:Mechano-catalytic Overall Water Splitting on Cu2O, NiO, and Co3O4 was investigated in order to reveal the reaction mechanism. The experimental results indicated that metallic elements of these oxides were generated during the reaction. Also, elemental metals Cu, Ni, and Co were oxidized into Cu2O, NiO, and Co3O4, respectively, when Water was reduced into H2 by the metal powders under the same reaction condition. The metallic particles covered with the metal oxides evolved both O2 and H2. These results suggest that a redox reaction between the metal and metal oxide may be responsible for H2 and O2 formation of the mechano-catalytic Overall Water Splitting.
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Mechano-catalysis—a novel method for Overall Water Splitting
Physical Chemistry Chemical Physics, 1999Co-Authors: Shigeru Ikeda, Kazunari Domen, Tsuyoshi Takata, Michikazu Hara, Junko N. Kondo, Mutsuko Komoda, Akira Tanaka, Hideo Hosono, Hiroshi KawazoeAbstract:A novel finding of mechano-catalytic Overall Water Splitting by metal oxides, a way to produce hydrogen by Water decomposition, is reported. It was clearly revealed that some simple and mixed oxide powders such as NiO, Co3O4, Cu2O, Fe3O4, and CuMO2 (M=Al, Fe, Ga), when suspended in distilled Water by magnetic stirring, decompose Water into H2 and O2 catalytically. The observed mechano-catalytic Overall Water Splitting was cycled by the conversion of mechanical energy supplied by rubbing these oxide powders against the bottom wall of the reaction vessel with the stirring rod. Typical efficiency of the mechanical-to-chemical energy conversion was estimated to be 4.3% (for NiO).
Mingwen Zhao - One of the best experts on this subject based on the ideXlab platform.
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Computational studies on triphenyldiyne as a two-dimensional visible-light-driven photocatalyst for Overall Water Splitting.
Physical Chemistry Chemical Physics, 2020Co-Authors: Yingcai Fan, Mingwen ZhaoAbstract:The high carrier mobility, porous configurations and tunable electronic structures of two-dimensional (2D) carbon materials hold great promise in energy conversion and storage. However, few of them is capable for photocatalytic Overall Water Splitting. Here, by means of first-principles calculations within the quasi-particle approximation and Bethe-Salpeter equation, we demonstrated a novel framework of triphenylenes (sp2) and acetylenic linkages (sp), namely triphenyldiyne (TDY) owns the electronic band structure suitable for photocatalytic Overall Water Splitting along with pronounced optical absorbance in visible light. The redox ability of the photogenerated electron is high enough to drive hydrogen evolution reaction (HER). Through Ni doping to TDY, the overpotential for oxygen evolution reaction (OER) can be reduced to match the redox ability of the photogenerated holes, enabling the photocatalytic Overall Water Splitting in the sunshine without the need of sacrificial reagents. This work offers not only a low-cost, earth-abundant and environmental-friendly photocatalyst, but also a promising strategy for designing highly-efficient photocatalysts for Overall Water Splitting.
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Computational studies on triphenyldiyne as a two-dimensional visible-light-driven photocatalyst for Overall Water Splitting.
Physical chemistry chemical physics : PCCP, 2020Co-Authors: Yingcai Fan, Mingwen ZhaoAbstract:The high carrier mobility, porous configurations and tunable electronic structures of two-dimensional (2D) carbon materials hold great promise in energy conversion and storage. However, few of them are capable of photocatalytic Overall Water Splitting. Here, by means of first-principles calculations within the quasi-particle approximation and the Bethe–Salpeter equation, we demonstrated a unique framework of triphenylenes (sp2) and acetylenic linkages (sp), namely triphenyldiyne (TDY) that has the electronic band structure suitable for photocatalytic Overall Water Splitting along with pronounced optical absorbance in visible light. The redox ability of its photogenerated electrons is high enough to drive the hydrogen evolution reaction (HER). Through Ni doping with TDY, its overpotential for the oxygen evolution reaction (OER) can be reduced to match the redox ability of its photogenerated holes, enabling the photocatalytic Overall Water Splitting in sunlight without the need of sacrificial reagents. This work offers not only a low-cost, earth-abundant and environmental-friendly photocatalyst, but also a promising strategy for designing highly efficient photocatalysts for Overall Water Splitting.
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Bifunctional Electrocatalytic Activity of Bis(iminothiolato)nickel Monolayer for Overall Water Splitting
The Journal of Physical Chemistry C, 2019Co-Authors: Xiaohan Song, Yingcai Fan, Junru Wang, Mingwen ZhaoAbstract:The bifunctional catalysts for the hydrogen and oxygen evolution reactions (HER and OER) with high efficiency, low cost, and easy integration for future renewable energy systems are highly desirable. Here, on the basis of first-principles calculations, we predicted a two-dimensional (2D) metal–organic framework (MOF) bifunctional electrocatalyst, namely, bis(iminothiolato)nickel (NiIT) monolayer, for Overall Water Splitting. The semi-metallic properties and low HER/OER overpotentials (−0.15/0.50 V) ensure the remarkable electrocatalytic performance of the 2D MOF electrocatalyst. The spatially separated HER and OER active sites with different electronegativities facilitate the electrocatalytic processes. Our findings highlight a promising precious-metal-free bifunctional electrocatalyst for efficient Overall Water Splitting, as well as a novel strategy in catalyst design.
