The Experts below are selected from a list of 170307 Experts worldwide ranked by ideXlab platform
Kazunari Domen - One of the best experts on this subject based on the ideXlab platform.
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particulate Photocatalysts for light driven water splitting mechanisms challenges and design strategies
Chemical Reviews, 2020Co-Authors: Qian Wang, Kazunari DomenAbstract:Solar-driven water splitting provides a leading approach to store the abundant yet intermittent solar energy and produce hydrogen as a clean and sustainable energy carrier. A straightforward route to light-driven water splitting is to apply self-supported particulate Photocatalysts, which is expected to allow solar hydrogen to be competitive with fossil-fuel-derived hydrogen on a levelized cost basis. More importantly, the powder-based systems can lend themselves to making functional panels on a large scale while retaining the intrinsic activity of the photocatalyst. However, all attempts to generate hydrogen via powder-based solar water-splitting systems to date have unfortunately fallen short of the efficiency values required for practical applications. Photocatalysis on photocatalyst particles involves three sequential steps: (i) absorption of photons with higher energies than the bandgap of the Photocatalysts, leading to the excitation of electron-hole pairs in the particles, (ii) charge separation and migration of these photoexcited carriers, and (iii) surface chemical reactions based on these carriers. In this review, we focus on the challenges of each step and summarize material design strategies to overcome the obstacles and limitations. This review illustrates that it is possible to employ the fundamental principles underlying photosynthesis and the tools of chemical and materials science to design and prepare Photocatalysts for overall water splitting.
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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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tethering metal ions to photocatalyst particulate surfaces by bifunctional molecular linkers for efficient hydrogen evolution
Chemsuschem, 2014Co-Authors: Tayirjan Taylor Isimjan, Kazunari Domen, Silvano Del Gobbo, Dalaver H Anjum, Safwat Abdelazeim, Luigi Cavallo, Angel T Garciaesparza, Kazuhiro TakanabeAbstract:A simple and versatile method for the preparation of photocatalyst particulates modified with effective cocatalysts is presented; the method involves the sequential soaking of photocatalyst particulates in solutions containing bifunctional organic linkers and metal ions. The modification of the particulate surfaces is a universal and reproducible method because the molecular linkers utilize strong covalent bonds, which in turn result in modified monolayer with a small but controlled quantity of metals. The photocatalysis results indicated that the CdS with likely photochemically reduced Pd and Ni, which were initially immobilized via ethanedithiol (EDT) as a linker, were highly efficient for photocatalytic hydrogen evolution from Na2S-Na2SO3-containing aqueous solutions. The method developed in this study opens a new synthesis route for the preparation of effective Photocatalysts with various combinations of bifunctional linkers, metals, and photocatalyst particulate materials.
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photocatalytic water splitting recent progress and future challenges
Journal of Physical Chemistry Letters, 2010Co-Authors: Kazuhiko Maeda, Kazunari DomenAbstract:Water splitting to form hydrogen and oxygen using solar energy in the presence of semiconductor Photocatalysts has long been studied as a potential means of clean, large-scale fuel production. In general, overall water splitting can be achieved when a photocatalyst is modified with a suitable cocatalyst. It is therefore important to develop both Photocatalysts and cocatalysts. In the past five years, there has been significant progress in water splitting photocatalysis, especially in the development of cocatalysts and related physical and materials chemistry. This work describes the state of the art and future challenges in photocatalytic water splitting, with a focus on the recent progress of our own research.
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ruo2 loaded β ge3n4 as a non oxide photocatalyst for overall water splitting
Journal of the American Chemical Society, 2005Co-Authors: Junya Sato, Kazuhiko Maeda, Kazunari Domen, Nobuo Saito, Yoko Yamada, Tsuyoshi Takata, Junko N Kondo, Michikazu Hara, Hisayoshi Kobayashi, Yasunobu InoueAbstract:Germanium nitride β-Ge3N4 dispersed with RuO2 nanoparticles is presented as the first example of a non-oxide photocatalyst for the stoichiometric decomposition of H2O into H2 and O2. All of the successful Photocatalysts developed for overall water splitting over the past 30 years have been based on oxides of metals. The discovery of a non-oxide photocatalyst, such as nitrides and oxynitrides, achieving the same function is therefore expected to stimulate research on non-oxide Photocatalysts. New opportunities for progress in the development of visible light-driven photocatalysis can thus be expected, as the higher valence band positions of metal nitrides compared to the corresponding metal oxides provide narrower band gaps, which are suitable for visible light activity.
Yongsheng Chen - One of the best experts on this subject based on the ideXlab platform.
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an alternative to in situ photocatalytic degradation of microcystin lr by worm like n p co doped tio2 expanded graphite by carbon layer npt egc floating composites
Applied Catalysis B-environmental, 2017Co-Authors: Xuejiang Wang, Jingke Song, Xin Tong, Jiayi Wang, Lijie Zhou, Jianfu Zhao, Xin Wang, Yongsheng ChenAbstract:Abstract In recent years, harmful algal blooms (HABs) frequently occur in eutrophic lakes all over the world. It causes the accumulation of microcystin-LR (MC-LR) in water, thus giving a great threat to aquatic animals and human beings. In this paper, a facile sol-carbonization method was used to synthesize N, P co-doped TiO 2 /expanded graphite by carbon layer (NPT-EGC) floating Photocatalysts, which are designed for in situ photocatalytic degradation of MC-LR. XRD, N 2 adsorption/desorption, FESEM/EDS, TEM, FTIR, XPS, UV–vis DRS and the PL spectrum were used to investigate the physicochemical and photoelectricity properties of the NPT-EGC Photocatalysts. The results showed that NPT-EGC has a worm-like structure with N, P co-doped TiO 2 particles distributed on the surface. The calcination temperatures have influences on the forming of TiO 2 and carbon layer, specific surface area and photocatalytic activity. Among the different NPT-EGC Photocatalysts, the photocatalyst calcined at 450 °C (NPT-EGC450) exhibited the strongest photo-absorption and the lowest recombination rate of photo-generated charge carrier. As a result, NPT-EGC450 achieved the highest removal rate of MC-LR (99.4%) following 9 h of irradiation, which is mostly attributed to photocatalytic degradation. LC–MS analysis showed most MC-LR molecules have been mineralized into small molecules. After three consecutive cycles, the NPT-EGC floating photocatalyst exhibited excellent reusability and stability, which indicates the floating photocatalysis is a promising technique for MC-LR degradation in the future.
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An alternative to in situ photocatalytic degradation of microcystin-LR by worm-like N, P co-doped TiO2/expanded graphite by carbon layer (NPT-EGC) floating composites
Applied Catalysis B-environmental, 2017Co-Authors: Xin Wang, Xuejiang Wang, Jingke Song, Xin Tong, Jiayi Wang, Lijie Zhou, Jianfu Zhao, Yongsheng ChenAbstract:Abstract In recent years, harmful algal blooms (HABs) frequently occur in eutrophic lakes all over the world. It causes the accumulation of microcystin-LR (MC-LR) in water, thus giving a great threat to aquatic animals and human beings. In this paper, a facile sol-carbonization method was used to synthesize N, P co-doped TiO2/expanded graphite by carbon layer (NPT-EGC) floating Photocatalysts, which are designed for in situ photocatalytic degradation of MC-LR. XRD, N2 adsorption/desorption, FESEM/EDS, TEM, FTIR, XPS, UV–vis DRS and the PL spectrum were used to investigate the physicochemical and photoelectricity properties of the NPT-EGC Photocatalysts. The results showed that NPT-EGC has a worm-like structure with N, P co-doped TiO2 particles distributed on the surface. The calcination temperatures have influences on the forming of TiO2 and carbon layer, specific surface area and photocatalytic activity. Among the different NPT-EGC Photocatalysts, the photocatalyst calcined at 450 °C (NPT-EGC450) exhibited the strongest photo-absorption and the lowest recombination rate of photo-generated charge carrier. As a result, NPT-EGC450 achieved the highest removal rate of MC-LR (99.4%) following 9 h of irradiation, which is mostly attributed to photocatalytic degradation. LC–MS analysis showed most MC-LR molecules have been mineralized into small molecules. After three consecutive cycles, the NPT-EGC floating photocatalyst exhibited excellent reusability and stability, which indicates the floating photocatalysis is a promising technique for MC-LR degradation in the future.
Xin Wang - One of the best experts on this subject based on the ideXlab platform.
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an alternative to in situ photocatalytic degradation of microcystin lr by worm like n p co doped tio2 expanded graphite by carbon layer npt egc floating composites
Applied Catalysis B-environmental, 2017Co-Authors: Xuejiang Wang, Jingke Song, Xin Tong, Jiayi Wang, Lijie Zhou, Jianfu Zhao, Xin Wang, Yongsheng ChenAbstract:Abstract In recent years, harmful algal blooms (HABs) frequently occur in eutrophic lakes all over the world. It causes the accumulation of microcystin-LR (MC-LR) in water, thus giving a great threat to aquatic animals and human beings. In this paper, a facile sol-carbonization method was used to synthesize N, P co-doped TiO 2 /expanded graphite by carbon layer (NPT-EGC) floating Photocatalysts, which are designed for in situ photocatalytic degradation of MC-LR. XRD, N 2 adsorption/desorption, FESEM/EDS, TEM, FTIR, XPS, UV–vis DRS and the PL spectrum were used to investigate the physicochemical and photoelectricity properties of the NPT-EGC Photocatalysts. The results showed that NPT-EGC has a worm-like structure with N, P co-doped TiO 2 particles distributed on the surface. The calcination temperatures have influences on the forming of TiO 2 and carbon layer, specific surface area and photocatalytic activity. Among the different NPT-EGC Photocatalysts, the photocatalyst calcined at 450 °C (NPT-EGC450) exhibited the strongest photo-absorption and the lowest recombination rate of photo-generated charge carrier. As a result, NPT-EGC450 achieved the highest removal rate of MC-LR (99.4%) following 9 h of irradiation, which is mostly attributed to photocatalytic degradation. LC–MS analysis showed most MC-LR molecules have been mineralized into small molecules. After three consecutive cycles, the NPT-EGC floating photocatalyst exhibited excellent reusability and stability, which indicates the floating photocatalysis is a promising technique for MC-LR degradation in the future.
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An alternative to in situ photocatalytic degradation of microcystin-LR by worm-like N, P co-doped TiO2/expanded graphite by carbon layer (NPT-EGC) floating composites
Applied Catalysis B-environmental, 2017Co-Authors: Xin Wang, Xuejiang Wang, Jingke Song, Xin Tong, Jiayi Wang, Lijie Zhou, Jianfu Zhao, Yongsheng ChenAbstract:Abstract In recent years, harmful algal blooms (HABs) frequently occur in eutrophic lakes all over the world. It causes the accumulation of microcystin-LR (MC-LR) in water, thus giving a great threat to aquatic animals and human beings. In this paper, a facile sol-carbonization method was used to synthesize N, P co-doped TiO2/expanded graphite by carbon layer (NPT-EGC) floating Photocatalysts, which are designed for in situ photocatalytic degradation of MC-LR. XRD, N2 adsorption/desorption, FESEM/EDS, TEM, FTIR, XPS, UV–vis DRS and the PL spectrum were used to investigate the physicochemical and photoelectricity properties of the NPT-EGC Photocatalysts. The results showed that NPT-EGC has a worm-like structure with N, P co-doped TiO2 particles distributed on the surface. The calcination temperatures have influences on the forming of TiO2 and carbon layer, specific surface area and photocatalytic activity. Among the different NPT-EGC Photocatalysts, the photocatalyst calcined at 450 °C (NPT-EGC450) exhibited the strongest photo-absorption and the lowest recombination rate of photo-generated charge carrier. As a result, NPT-EGC450 achieved the highest removal rate of MC-LR (99.4%) following 9 h of irradiation, which is mostly attributed to photocatalytic degradation. LC–MS analysis showed most MC-LR molecules have been mineralized into small molecules. After three consecutive cycles, the NPT-EGC floating photocatalyst exhibited excellent reusability and stability, which indicates the floating photocatalysis is a promising technique for MC-LR degradation in the future.
Shizhang Qiao - One of the best experts on this subject based on the ideXlab platform.
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2d phosphorene as a water splitting photocatalyst fundamentals to applications
Energy and Environmental Science, 2016Co-Authors: Mohammad Ziau Rahma, C W Kwong, K R Davey, Shizhang QiaoAbstract:Hydrogen from direct splitting of water molecules using photons is reckoned to be a sustainable and renewable energy solution for the post fossil-fuel era. Efficient Photocatalysts, including metal-free Photocatalysts, are key determinants of cost-effective hydrogen generation at a large-scale. The search for new materials that are metal-free is therefore ongoing. Recently, 2D phosphorene, a phosphorus analogue of graphene, has been added as a new semiconductor to the family of monolayer-flatland materials. In this review, we focus on analysing the fundamental electronic, optical and chemical properties of 2D phosphorene and assess its suitability as a metal-free water splitting photocatalyst. We also critically analyse its stability against claims from environmental antagonists and attempt to predict its future as a photocatalyst. This review provides timely information for researchers, scientists and professionals devoted to materials research for photocatalysis.
Maria Cristina Canela - One of the best experts on this subject based on the ideXlab platform.
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tio2 sol gel for formaldehyde photodegradation using polymeric support photocatalysis efficiency versus material stability
Environmental Science and Pollution Research, 2015Co-Authors: Monique Seufitellis Curcio, Michel P Oliveira, Walter R Waldman, Benigno Sanchez, Maria Cristina CanelaAbstract:Photocatalysts supported on polymers are not frequently used in heterogeneous photocatalysis because of problems such as wettability and stability that affect photocatalysis conditions. In this work, we used polypropylene as support for TiO2 sol-gel to evaluate its stability and efficiency under UV radiation. We also tested the effect of the thermo-pressing PP/TiO2 system on the photocatalytic efficiency and stability under UV radiation. The films were characterized by scanning electron microscopy (SEM), UV-Vis spectroscopy and X-ray diffraction (XRD). The SEM micrographs showed that the films of TiO2 sol-gel onto PP has approximately 1.0-μm thick and regular surface and the generation of polypropylene nanowires on hot-pressed samples. XRD showed the formation of TiO2 anatase on the surface of the films made by dip-coating. All Photocatalysts were tested in decontaminating air-containing gaseous formaldehyde (70 ppmv) presenting degradation of the target compound to the limit of detection. The Photocatalysts showed no deactivation during the entire period tested (30 h), and its reuse after washing showed better photocatalytic performance than on first use. The photocatalyst showed the best results were tested for 360 h with no observed deactivation. Aging studies showed that the film of TiO2 causes different effects on the photostability of composites, with stabilizing effect when exposed to most energetic UVC radiation (λmax = 254 nm) and degradative effects when exposed to UVA radiation (λmax = 365 nm).
