Photothermal-enabled single-atom catalysts for high-efficiency hydrogen peroxide photosynthesis from natural seawater

Hydrogen peroxide (H(2)O(2)) is a powerful industrial oxidant and potential carbon-neutral liquid energy carrier. Sunlight-driven synthesis of H(2)O(2) from the most earth-abundant O(2) and seawater is highly desirable. However, the solar-to-chemical efficiency of H(2)O(2) synthesis in particulate photocatalysis systems is low. Here, we present a cooperative sunlight-driven photothermal-photocatalytic system based on cobalt single-atom supported on sulfur doped graphitic carbon nitride/reduced graphene oxide heterostructure (Co–CN@G) to boost H(2)O(2) photosynthesis from natural seawater. By virtue of the photothermal effect and synergy between Co single atoms and the heterostructure, Co–CN@G enables a solar-to-chemical efficiency of more than 0.7% under simulated sunlight irradiation. Theoretical calculations verify that the single atoms combined with heterostructure significantly promote the charge separation, facilitate O(2) absorption and reduce the energy barriers for O(2) reduction and water oxidation, eventually boosting H(2)O(2) photoproduction. The single-atom photothermal-photocatalytic materials may provide possibility of large-scale H(2)O(2) production from inexhaustible seawater in a sustainable way.