Wang Yingying, Huang Jincheng, Chen Yuxuan, Yang Hao, Ye Kai-Hang, Huang Yongchao
Institute of Environmental Research at Greater Bay Area; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education; Guangzhou University; Guangdong Provincial Key Laboratory of Fuel Cell Technology, Guangzhou, 510006, China.
School of Chemistry & Chemical Engineering, Guangxi Key Laboratory of Electrochemical Energy Materials, Guangxi Colleges and Universities Key Laboratory of Applied Chemistry Technology and Resource Development, Guangxi University, Nanning, 530004, China.
J Colloid Interface Sci. 2024 Oct 15;672:12-20. doi: 10.1016/j.jcis.2024.05.218. Epub 2024 May 31.
Photoelectrochemical (PEC) water splitting on semiconductor electrodes is considered to be one of the important ways to produce clean and sustainable hydrogen fuel, which is a great help in solving energy and environmental problems. Bismuth vanadate (BiVO) as a promising photoanode for photoelectrochemical water splitting still suffers from poor charge separation efficiency and photo-induced self-corrosion. Herein, we develop heterojunction-rich photoanodes composed of BiVO and iron vanadate (FeVO), coated with nickel iron oxide (NiFeO/FeVO/BiVO). The formation of the interface between BiVO and FeVO (Bi-VO-Fe bridges) enhances the interfacial interaction, resulting in improved performance. Meanwhile, high-conductivity FeVO and NiFeO oxygen evolution co-catalysts effectively enhance bulk electron/hole separation, interface water's kinetics and photostability. Concurrently, the optimized NiFeO/FeVO/BiVO possesses a remarkable photocurrent density of 5.59 mA/cm at 1.23 V versus reversible hydrogen electrode (vs RHE) under AM 1.5G (Air Mass 1.5 Global) simulated sunlight, accompanied by superior stability without any decreased of its photocurrent density after 14 h. This work not only reveals the crucial role of built-in electric field in BiVO-based photoanode during PEC water splitting, but also provides a new guide to the design of efficient photoanode for PEC.
半导体电极上的光电化学（PEC）水分解被认为是生产清洁且可持续的氢燃料的重要途径之一，这对解决能源和环境问题有很大帮助。钒酸铋（BiVO）作为一种有前景的用于光电化学水分解的光阳极，仍然存在电荷分离效率低和光致自腐蚀的问题。在此，我们开发了由BiVO和钒酸铁（FeVO）组成的富含异质结的光阳极，其表面涂覆有镍铁氧化物（NiFeO/FeVO/BiVO）。BiVO和FeVO之间界面（Bi-VO-Fe桥）的形成增强了界面相互作用，从而提高了性能。同时，高导电性的FeVO和NiFeO析氧共催化剂有效地增强了体相电子/空穴分离、界面水的动力学和光稳定性。此外，优化后的NiFeO/FeVO/BiVO在AM 1.5G（空气质量1.5全球）模拟阳光下，相对于可逆氢电极（vs RHE）在1.23 V时具有5.59 mA/cm²的显著光电流密度，并且具有优异的稳定性，在14小时后其光电流密度没有任何下降。这项工作不仅揭示了PEC水分解过程中基于BiVO的光阳极中内建电场的关键作用，还为PEC高效光阳极的设计提供了新的指导。
