BiVO₄ Heterojunctions as Efficient Photoanodes for Photoelectrochemical Water Oxidation

Abstract

Photoelectrochemical (PEC) water splitting has attracted strong interest as sustainable technology by converting solar energy into hydrogen. The semiconductor photoelectrodes play an important role to crease the solar‐to‐hydrogen conversion efficiency. Bismuth vanadate (BiVO4) is an excellent candidate as a photoanode material for PEC water oxidation because of its visible light absorption, suitable band edge location, high stability and low cost. However, single BiVO4 may undergo short carrier diffusion length, rapid recombination of photoinduced charge carriers and photocorrosion. Heterojunction strategy established by two or more materials has provided an outstanding scheme to mitigate these inadequacies. This review focuses on recent important works with respect to BiVO4 heterojunction photoanodes for PEC water oxidation reactions, including interface junction and surface functional junction. In the end, the challenges and prospects for future research on BiVO4 heterojunction photoanodes in solar‐to‐hydrogen application field are proposed.

State of the Art Progress in Copper Vanadate Materials for Solar Water Splitting

“…Metal vanadates (MVs) have demonstrated promising photocatalytic and PEC properties due to narrow bandgaps, suitable band edge positions for oxygen evolution reactions (OER), electrical properties, and stability [ 53 , 54 ]. For example, BiVO 4 is the widely explored MV in photocatalytic and PEC studies, owing this to its bandgap alignment, optical absorption, and catalytic properties [ 55 ]. Even though the unique oxygen–vanadium bond in MVs offers superior charge storage properties, their utilization as photoelectrodes has been extensively explored, owing this to their favorable optical and electrical properties.…”

“…The hybridized O 2p orbital in M x V y O z structures offers facile regulation of both the Fermi level and the band edge positions, allowing the tuning of optical, band edge, and catalytic properties in favor of water splitting reactions. Importantly, the stable presence of second metal elements in M x V y O z crystals along with vanadium and oxygen species provides a synergistic effect that favors catalytic effects in both electrochemical and PEC applications [ 55 ].…”