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991.
The development of transition‐metal‐oxides (TMOs)‐based bifunctional catalysts toward efficient overall water splitting through delicate control of composition and structure is a challenging task. Herein, the rational design and controllable fabrication of unique heterostructured inter‐doped ruthenium–cobalt oxide [(Ru–Co)Ox] hollow nanosheet arrays on carbon cloth is reported. Benefiting from the desirable compositional and structural advantages of more exposed active sites, optimized electronic structure, and interfacial synergy effect, the (Ru–Co)Ox nanoarrays exhibited outstanding performance as a bifunctional catalyst. Particularly, the catalyst showed a remarkable hydrogen evolution reaction (HER) activity with an overpotential of 44.1 mV at 10 mA cm?2 and a small Tafel slope of 23.5 mV dec?1, as well as an excellent oxygen evolution reaction (OER) activity with an overpotential of 171.2 mV at 10 mA cm?2. As a result, a very low cell voltage of 1.488 V was needed at 10 mA cm?2 for alkaline overall water splitting. 相似文献
992.
Xiuxiu Han Steffen Heuser Dr. Xili Tong Dr. Nianjun Yang Prof. Dr. Xiang-Yun Guo Prof. Dr. Xin Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3586-3590
Cubic silicon carbide (3C-SiC) material feature a suitable bandgap and high resistance to photocorrosion. Thus, it has been emerged as a promising semiconductor for hydrogen evolution. Here, the relationship between the photoelectrochemical properties and the microstructures of different SiC materials is demonstrated. For visible-light-derived water splitting to hydrogen production, nanocrystalline, microcrystalline and epitaxial (001) 3C-SiC films are applied as the photocathodes. The epitaxial 3C-SiC film presents the highest photoelectrochemical activity for hydrogen evolution, because of its perfect (001) orientation, high phase purity, low resistance, and negative conduction band energy level. This finding offers a strategy to design SiC-based photocathodes with superior photoelectrochemical performances. 相似文献
993.
Yuan Lin Prof. Wenyue Su Prof. Xuxu Wang Prof. Xianzhi Fu Prof. Xinchen Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(47):21105-21109
It is a challenge to explore photocatalytic materials for sunlight-driven water splitting owing to the limited choice of a single semiconductor with suitable band energy levels but with a minimized band gap for light harvesting. Here, we report a one-photon excitation pathway by coupling polymeric carbon nitride (PCN) semiconductor with LaOCl to achieve overall water splitting. This artificial photosynthesis composite catalyzes the decomposition of H2O into H2 and O2, with evolution rates of 22.3 and 10.7 μmol h−1, respectively. The high photocatalytic performance of PCN/LaOCl can be ascribed to the simultaneously accomplished reduction and oxidation of water on LaOCl and PCN domains, respectively, as well as the fast charge separation and migration induced by the interfacial electric field related to LaOCl modification. This study provides new insights on the development of composite photocatalysts for pure water splitting based on polymer-based materials via charge modulation. 相似文献
994.
Dr. Takayoshi Oshima Dr. Tom Ichibha Kenji Oqmhula Dr. Keisuke Hibino Hiroto Mogi Dr. Shunsuke Yamashita Prof. Dr. Kotaro Fujii Dr. Yugo Miseki Prof. Dr. Kenta Hongo Dr. Daling Lu Prof. Dr. Ryo Maezono Dr. Kazuhiro Sayama Prof. Dr. Masatomo Yashima Dr. Koji Kimoto Prof. Dr. Hideki Kato Prof. Dr. Masato Kakihana Prof. Dr. Hiroshi Kageyama Prof. Dr. Kazuhiko Maeda 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9823-9830
Undoped layered oxynitrides have not been considered as promising H2-evolution photocatalysts because of the low chemical stability of oxynitrides in aqueous solution. Here, we demonstrate the synthesis of a new layered perovskite oxynitride, K2LaTa2O6N, as an exceptional example of a water-tolerant photocatalyst for H2 evolution under visible light. The material underwent in-situ H+/K+ exchange in aqueous solution while keeping its visible-light-absorption capability. Protonated K2LaTa2O6N, modified with an Ir cocatalyst, exhibited excellent catalytic activity toward H2 evolution in the presence of I− as an electron donor and under visible light; the activity was six times higher than Pt/ZrO2/TaON, one of the best-performing oxynitride photocatalysts for H2 evolution. Overall water splitting was also achieved using the Ir-loaded, protonated K2LaTa2O6N in combination with Cs-modified Pt/WO3 as an O2 evolution photocatalyst in the presence of an I3−/I− shuttle redox couple. 相似文献
995.
Kazuhiko MaedaAuthor vitae 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2011,12(4):237-268
Overall water splitting to produce H2 and O2 over a semiconductor photocatalyst using solar energy is a promising process for the large-scale production of clean, recyclable H2. Numerous attempts have been made to develop photocatalysts that function under visible-light irradiation to efficiently utilize solar energy. In general, overall water splitting over a photocatalyst particle can be achieved by modifying the photocatalyst with a suitable cocatalyst to provide an active redox site. Therefore, the development of active photocatalytic materials has relied on both photocatalysts and cocatalysts. This review article describes the historical development of water-splitting photocatalysts. 相似文献
996.
Can Li Dr. Zheng Chen Dr. Hong Yi Yi Cao Dr. Lei Du Dr. Yidong Hu Fanpeng Kong Prof. Dr. Richard Kramer Campen Prof. Dr. Yunzhi Gao Prof. Dr. Chunyu Du Prof. Dr. Geping Yin Prof. Dr. Igor Ying Zhang Dr. Yujin Tong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16036-16041
The essence of developing a Pt-based single-atom catalyst (SAC) for hydrogen evolution reaction (HER) is the preparation of well-defined and stable single Pt sites with desired electrocatalytic efficacy. Herein, we report a facile approach to generate uniformly dispersed Pt sites with outstanding HER performance via a photochemical reduction method using polyvinylpyrrolidone (PVP) molecules as the key additive to significantly simplify the synthesis and enhance the catalytic performance. The as-prepared catalyst displays remarkable kinetic activities (20 times higher current density than the commercially available Pt/C) with excellent stability (76.3 % of its initial activity after 5000 cycles) for HER. EXAFS measurements and DFT calculations demonstrate a synergetic effect, where the PVP ligands and the support together modulate the electronic structure of the Pt atoms, which optimize the hydrogen adsorption energy, resulting in a considerably improved HER activity. 相似文献
997.
《中国化学快报》2020,31(7):1773-1781
Semiconductor-based photoelectrocatalytic processes have attracted considerable research interest for solar energy collection and storage. Photoelectrocatalysis is a heterogeneous photocatalytic process in which a bias potential is applied to a photoelectrode, and thus the photoelectrocatalytic performance is closely related to the photoelectrode prepared by semiconductors. Among various semiconductors, metal-organic frameworks (MOFs) have attracted more and more attention because of their unique properties such as optical properties and adjustable structure. Herein, a comprehensive review on different MOFs (Ti-based, Zn-based, Co-based, Fe-based, Cu-based, and mixed metal-based MOFs) for heterogeneous photoelectrocatalysis is carried out and, in particular, the application of this technique for CO2 conversion and water splitting is discussed. In addition, the challenges and development prospects of MOFs in photoelectrocatalysis are also presented. 相似文献
998.
Two-Dimensional GaTe/Bi2Se3 Heterostructure: a Promising Direct Z-scheme Water Splitting Photocatalyst 下载免费PDF全文
Among various photocatalytic materials, Z-scheme photocatalysts have drawn tremendous research interest due to high photocatalytic performance in solar water splitting. Here, we perform extensive hybrid density functional theory calculations to explore electronic structures, interfacial charge transfer, electrostatic potential profile, optical absorption properties, and photocatalytic properties of a proposed two-dimensional (2D) small-lattice-mismatched GaTe/Bi\begin{document}$ _2 $\end{document} Se\begin{document}$ _3 $\end{document} heterostructure. Theoretical results clearly reveal that the examined heterostructure with a small direct band gap can effectively harvest the broad spectrum of the incoming sunlight. Due to the relative strong interfacial built-in electric field in the heterostructure and the small band gap between the valence band maximum of GaTe monolayer and the conduction band minimum of Bi\begin{document}$ _2 $\end{document} Se\begin{document}$ _3 $\end{document} nanosheet with slight band edge bending, these photogenerated carriers transfer via Z-scheme pathway, which results in the photogenerated electrons and holes effectively separating into the GaTe monolayer and the Bi\begin{document}$ _2 $\end{document} Se\begin{document}$ _3 $\end{document} nanosheet for the hydrogen and oxygen evolution reactions, respectively. Our results imply that the artificial 2D GaTe/Bi\begin{document}$ _2 $\end{document} Se\begin{document}$ _3 $\end{document} is a promising Z-scheme photocatalyst for overall solar water splitting. 相似文献
999.
To rationally design efficient and cost‐effective electrocatalysts, a simple but efficient strategy has been developed to directly anchor prussian blue analogue (PBA) nanocubes on cobalt hydroxide nanoplates (PBA@Co(OH)2) via the in‐situ interfacial precipitation process. Subsequently, the thermal treatment in the presence of sodium hydrogen phosphite enabled the successful transition into metal phosphides with the hierarchical cube‐on‐plate structure. When used as electrocatalytsts, the obtained bimetal phosphides exhibited good bifunctional electrocatalytic activities for hydrogen and oxygen evolution reactions with good long‐term stability. Thus, an enhanced performance for overall water splitting can be achieved, which could be ascribed to the hierarchical structure and favorable composition of as‐prepared bimetal phosphide for rapid electron and mass transfer. The present study demonstrates a favorable approach to modulate the composition and structure of metal phosphide for enhancing the electrocatalytic ability toward water splitting. 相似文献
1000.
To achieve efficient water splitting, it is essential to develop catalysts with high electrochemical performance, enhanced durability and tunable properties. Most of the transition metal‐based catalysts employed for the water splitting have been fabricated on the solid‐electrode support by using binder, which decreases the activity and durability of the catalyst system. In this respect, self‐supported metal organic framework (MOF) derived catalysts have been introduced with enhanced catalytic activity and mechanical stability for the electrochemical water splitting. The self‐supported MOF derived catalysts exhibit improved electronic conductivity, high electrochemical surface area, enhanced mechanical stability and strong catalyst‐support interaction. Moreover, these catalysts possess highly porous and hollow structure with designed morphology and multi‐metallic composition. Recently, a tremendous effort has been provided to explore this newly growing field and new dimensions and directions have been achieved. Looking at this point, we have described here the basic principles of catalyst design from self‐supported MOF, structural and interface engineering by controlling the electronic structure of the catalysts to improve the water splitting activity. In addition, the challenges and difficulties associated with this field have been pointed out and addressed for the future progress in this field. 相似文献