An efficient hydrogen evolution photocatalyst of Rh@Cr2O3-loaded PbMoO4 twenty-six facet polyhedrons

Abstract

Shape anisotropic semiconductors are advanced catalysts for resolving energy crises. However, modification studies are still needed to overcome their intrinsic disadvantages, such as the lack of active sites. With this aim, an excellent hydrogen evolution photocatalyst Rh@Cr₂O₃-loaded PbMoO₄ twenty-six facet polyhedron (PM/Rh@Cr₂O₃) has been synthesized by a liquid method. Based on XPS, electrochemical investigation and hydrogen evolution reaction (HER) test, it is demonstrated that Rh acts as an electron collector and active site; moreover, Cr₂O₃ can assist Rh in the dissociation of water. In addition, Cr₂O₃ can also inhibit the reverse reaction of water splitting as well as the mass transfer of water. In conclusion, the H₂ yield rate increased from 0 μmol g⁻¹ h⁻¹ of PbMoO₄ (PM) to 704 μmol g⁻¹ h⁻¹ of PM/Rh@Cr₂O₃, and PM/Rh@Cr₂O₃ exhibited excellent photo-stability.