An MgO passivation layer and hydrotalcite derived spinel Co2AlO4 synergically promote photoelectrochemical water oxidation conducted using BiVO4-based photoanodes

to capture the electrode/electrolyte interface for efficient water oxidation reaction. In order to understand the origin of this improvement, first-principles calculations with density functional theory (DFT) were performed. The theoretical investigation converges to our experimental results. This work proposes a novel idea for restraining the recombination of photogenerated carriers between interfaces and the rational design of efficient photoanodes.