CuOx–TiO2 junction: what is the active component for photocatalytic H2 production?

Abstract

CuO_x based junctions e.g. CuO_x–TiO₂ have been demonstrated to be very effective in photocatalytic H₂ production, but the active component at the junction is less understood. We herein report that an as-prepared CuO_x–TiO₂ photocatalyst undergoes an in situ restructuring process during photocatalytic H₂ production under solar light irradiation to form the active Cu₂O–TiO₂ interfacial structure on the surface. These results unambiguously demonstrate that Cu₂O is the active copper species in CuO_x–TiO₂ photocatalysts.