Conductive polymer modified β-FeOOH loaded onto BiVO4 for enhanced photocorrosion inhibition and photoelectrochemical performance

Bismuth vanadate (BiVO₄, BVO) is an ideal photoabsorber for the photoelectrocatalytic water splitting, but its performance and photostability limit its commercial application. Therefore, enhancing the catalytic performance and stability becomes an increasingly crucial issue. In this study, we report a composite catalytic material poly (3,4-ethylenedioxythiophene, EDOT) (PEDOT)-modified β-FeOOH nanosheets loading onto the surface of BVO through the hydrolysis of Fe³⁺ in BVO semiconductor film and the catalytic polymerization of EDOT form the conductive polymer. The structure facilitates the catalytic process, and when it is used in photoelectrocatalysis oxygen evolution reaction, it exhibits a photocurrent density of 3.3 mA cm⁻² at 1.23 V versus standard hydrogen electrodes. Mechanistic studies show that the introduction of PEDOT-modified β-FeOOH optimized the electrode/electrolyte contact interface, adjusted the defect state, and provided catalytically active sites during the catalytic process. This study provides a feasible idea for exploring the catalytic mechanism of BVO-based photoelectrode and designing catalysts.