Promotional effects of MoP on its efficient electro-photo catalysis of Pt-MoP-MoO3/C catalyst for hydrogen evolution

•Pt-MoP-MoO3/C was obtained via integration of Pt and Mo species on Carbon black (Vulcan-C).•Vulcan-C was employed to promote the uniform dispersion of Pt, MoP and MoO3.•Pt-MoP-MoO3/C exhibits superior electrocatalytic activity for HER, with better durability.•Synergy between electro and photo catalysis greatly enhances Pt catalytic capacity.•The amount of H2 produced on Pt-MoP-MoO3/C under irradiation is 5557.93 mmol h−1 g−1.