The Role of Underlayers and Overlayers in Thin Film BiVO4 Photoanodes for Solar Water Splitting

Abstract

Light‐driven water splitting with metal oxide semiconductor materials to produce H2 constitutes one of the most promising energy conversion technologies built on solar power. BiVO4 stands out as one of the most attractive metal oxides with reported photocurrents close to its theoretical maximum of 7.5 mA cm−2 at 1 sun illumination. The present work addresses the state‐of‐the‐art strategies to enhance the performance of this material for water oxidation by heterostructuring with different underlayer (SnO2 and WO3) and overlayer (NiOOH/FeOOH, Co–Pi, Co–Fe Prussian Blue derivative) materials, with particular emphasis on the physico‐chemical mechanisms responsible for the reported enhancements.