▎ 摘　　要

A Co3O4/reduced graphene oxide (rGO)/BiVO4 photoanode structure is fabricated for achieving excellent photoelectrochemical (PEC) water splitting performance. rGO behaving as a metal extracts holes from the underlying BiVO4 light absorption layer and Co3O4 plays the role of a catalyst for the oxygen evolution reaction. The Co3O4/rGO/BiVO4 photoanode shows a remarkable photocurrent density of 2.8 mA cm(-2) at 2 V versus the reversible hydrogen electrode (RHE) under AM 1.5G solar light irradiation, which is a four-fold increase compared to that of pristine BiVO4. The photocurrent generated by coating of the catalytic Co3O4 and rGO layers onto BiVO4 is similar to 93% of that generated in an electrolyte with a hole scavenger, which demonstrates the critical roles of the Co3O4 and rGO catalysts in the high PEC water splitting performance of the Co3O4/rGO/BiVO4 photoanode. The fabricated photoelectrode also shows highly stable photocurrent density for at least 3 h. (C) 2020 Elsevier Ltd. All rights reserved.