Hierarchical mesoporous SnO2/BiVO4 photoanode decorated with Ag nanorods for efficient photoelectrochemical water splitting

Bismuth vanadate has been extensively investigated as a potential visible light photoanode for PEC water splitting. The performance of BiVO4 is restricted by fast charge recombination and slow oxygen evolution reaction kinetic. To address these issues, hierarchical SnO2 (HSN) mesoporous support is developed via a novel sol-electrophoretic approach, and BiVO4 film is decorated with silver nanorods (Ag NRs). The photocurrent density of HSN/BiVO4 photoanode is 3.98 mA/cm(2) at 1.23 V vs. reversible hydrogen electrode (RHE) and onset potential (V-onset) of 0.5 V vs. RHE. The PEC performance is attributed to the appropriate band alignment between SnO2 and BiVO4, as well as the hierarchical structure of SnO2. Ag-HSN/BiVO4 photoanode shows photocurrent density of 4.30 mA/cm(2) at 1.23 V vs. RHE and V-onset of 0.28 V vs. RHE. The enhanced photocurrent and negatively shifted V-onset can be attributed to radiative localized surface plasmon resonance decay and catalytic effect of Ag NRs, respectively. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.