Facile growth of AgVO3 nanoparticles on Mo-doped BiVO4 film for enhanced photoelectrochemical water oxidation

BiVO 4 is largely restricted by its intrinsic poor electron mobility and sluggish surface reaction. Aiming at eliminating the deficiency of BiVO 4 , we assemble a novel composite photoanode through simultaneous bulk and surface modification. In detail, controllable Mo doping is manipulated through a spin-coating method, and AgVO 3 nanoparticles are loaded by successive ionic layer adsorption and reaction (SILAR) process. The as-prepared photoanode boosts the photocurrent density by 7 folds at 1.23 V vs. RHE and moves the onset potential negatively by 387 mV compared to the bare BiVO 4 . Furthermore, the charge injection efficiency is substantially boosted to 49% at 1.23 V RHE , nearly 5 times as that of pure BiVO 4 . With detailed physical and electrochemical characterization, we reveal the essential reason for the boosted photoelectrochemical activity. Appropriate Mo doping can simultaneously enhance the carrier density and electron mobility of BiVO 4 . Specifically, more (0 4 0) facet are exposed for retarding charge recombination and increasing photocatalytic reaction sites. Then the simple SILAR process grows AgVO 3 nanoparticles homogeneously with uniform diameter of 3–5 nm on BiVO 4 , forming p-n heterojunction to accelerate charge separation, and abundant oxygen vacancy emerged on the surface, which has been demonstrated as active sites for water oxidation reaction.