Dip-coating synthesis of P-doped BiVO4 photoanodes with enhanced photoelectrochemical performance

Abstract The application of bismuth vanadate for photoelectrochemical water splitting is limited by the insufficient charge separation and transport characteristics. In this work, phosphorus doped BiVO 4 (P-BiVO 4 ) photoanodes were fabricated through dip-coating method and subsequent thermal treatment process. The optimized 2% P-BiVO 4 exhibited a photocurrent density up to 0.28 mA/cm 2 at 1.23 V versus reversible hydrogen electrode in 0.5 M Na 2 SO 4 electrolyte (AM 1.5 G, 100 mW/cm 2 ). The incident photon-to-current efficiency of 2% P-BiVO 4 was boosted to 33%, which was significantly higher than the pristine BiVO 4 photoanode. The X-ray photoelectron spectra indicate that the P-BiVO 4 possessed abundant oxygen vacancies, which can account for enhancing PEC performance of P-BiVO 4 . The electrochemical impedance spectroscopy and Mott–Schottky results further show that P-BiVO 4 possess less interface obstruction and high carrier concentration, which were beneficial for the improvement of photoelectrochemical performance. This work provides a useful guidance for the design of non-metal doped BiVO 4 photoanodes for energy conversion.