▎ 摘　　要

NOVELTY - Photoanode comprises a base layer, a dielectric passivation layer and a sandwich composite layer arranged in sequence. The sandwich composite layer includes a metal oxide layer, a graphene layer and a metal layer stacked in sequence, and the metal oxide layer is in contact with the dielectric passivation layer. The thickness of the metal layer is 1.5-3.5 nm. USE - Photoanode is useful for photoelectrochemical decomposition of water and oxygen evolution (claimed) and used as catalytic carrier of electrocatalyst. ADVANTAGE - The photoanode has improved optical voltage, improved photoelectrochemical oxygen evolution performance from both thermodynamics and kinetics, and the preparation process is simple and controllable, so it has good application potential. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a preparing the photoanode. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of sandwich structure of metal oxide layer/graphene layer/metal layer in photoanode. 1Metal oxide layer 2Graphene layer 3Metal layer