The impact of iron-boron electrocatalysts on the charge transport and oxygen evolution reaction of bismuth vanadate photoanodes.

BiVO 4 possesses a suitable band gap for photoelectrochemical (PEC) water splitting to produce hydrogen; however, the performance of BiVO 4 is limited by several adverse factors. The bulk charge recombination and the slow surface water oxidation reaction of BiVO 4 are main unfavorable factors. In view of these disadvantages, an Fe-B i electrocatalyst is loaded on BiVO 4 to improve the PEC performance of BiVO 4 . After modification, the onset potential of BiVO 4 shifts negatively by 60 mV, and the saturated photocurrent is greatly increased. Systematic studies demonstrate that the Fe-B i electrocatalyst not only enhances the bulk charge separation, but also accelerates the surface water oxidation rate of BiVO 4 and greatly reduces the resistance of the reaction interface.