Defective Photocathode: Fundamentals, Construction, and Catalytic Energy Conversion

Abstract

The development of a long‐term and sustainable energy economy is one of the most significant technological challenges facing humanity. Photoelectrochemical (PEC) technology is considered as the most attractive route for converting solar energy into chemical energy. However, the slow reaction kinetics of PEC oxidation and reduction greatly hinder its practical application. To address this issue, engineering photoelectrodes with various defects can significantly improve their catalytic performance, which can not only regulate catalyst electronic structure but also promote charge transfer/separation by serving as an active/adsorption/energy storage site. Herein, the defect engineering strategies for photoelectrodes are systematically summarized, focusing on the latest progress in defective photocathode for energy conversion. First, an overview of defect types, basic principles of photocathode, and the positive role of defects in the photocathode are provided. Second, the construction strategies and characterization methods of defective photocathode are summarized. Then, the progress of typical energy conversion applications, including hydrogen production, CO2 reduction, and nitrogen reduction over defective photocathode, is reviewed, highlighting the crucial role of defects in high catalytic performance. Finally, the challenges and future prospects of defective photocathode are discussed, aiming to bring new opportunities for the development of photocathode through defect engineering.

Modulation of charge-transfer behavior via adaptive interface treatment for efficient photoelectrochemical water splitting

“…Solar-driven photoelectrochemical (PEC) water splitting has been broadly regarded as a promising solution for sustainable and decarbonized technology in the quest of green and renewable energy. 1–7 Since TiO 2 photoanodes, researched by Fujishima and Honda, 8,9 were employed to perform water splitting to produce hydrogen, a majority of semiconductors, for example, TiO 2 , 10 α-Fe 2 O 3 , 11–14 Ta 3 N 5 , 15,16 and BiVO 4 , 17–22 have been regarded as ideal photoanodes for PEC water splitting in recent years. Among various candidates, BiVO 4 is the most promising candidate for PEC water oxidation because of a low bandgap (2.4 eV), low cost, and ideal band-edge positions.…”