A tungsten phosphide cocatalyst enhanced bismuth tungstate photoanode with the robust built-in electric field towards highly efficient photoelectrochemical water splitting.

The use of low-cost and effective cocatalyst is a potential strategy to optimize the effectiveness of photoelectrochemical (PEC) water splitting. In this study, tungsten phosphide (WP) is introduced as a remarkably active cocatalyst to enhance the PEC efficiency of a BiWO photoanode. The onset potential of BiWO/WP demonstrates a negative shift, while the photocurrent density demonstrates a significant 5.