Novel PtPd alloy nanoparticle-decorated g-C3N4nanosheets with enhanced photocatalytic activity for H2evolution under visible light irradiation

PtPd bimetallic alloy nanoparticle (NP)-modified graphitic carbon nitride (g-C3N4) nanosheet photocatalysts were synthesized via chemical deposition precipitation. Characterization of the photocatalytic H2evolution of the g-C3N4nanosheets shows that it was significantly enhanced when PtPd alloy NPs were introduced as a co-catalyst. The 0.2 wt% PtPd/g-C3N4composite photocatalyst gave a maximum H2production rate of 1600.8 μmol g–1h–1. Furthermore, when K2HPO4was added to the reaction system, the H2production rate increased to 2885.0 μmol g–1h–1. The PtPd/g-C3N4photocatalyst showed satisfactory photocatalytic stability and was able to maintain most of its photocatalytic activity after four experimental photocatalytic cycles. In addition, a possible mechanism for the enhanced photocatalytic activity was proposed and verified by various photoelectric techniques. These results demonstrate that the synergistic effect between PtPd and g-C3N4helps to greatly improve the photocatalytic activity of the composite photocatalyst.