Shape-dependent hydrogen generation performance of PtPd bimetallic co-catalyst coupled with C3N4 photocatalyst

The shape-dependent performance of metal co-catalysts in photocatalysis has been one of the research focal points in recent years. In this study, PtPd/C3N4 hybrid structures were constructed to reveal the effect of the shape of the PtPd bimetallic co-catalyst on the performance of photocatalytic hydrogen generation. PtPd nanocubes (NCs) and nanotetrahedrons (NTs) were sequentially deposited in situ on the surface of C3N4 nanosheets, establishing a strong contact interface to ensure the smooth transfer of photoinduced electrons. Ultraviolet–visible (UV–Vis) diffuse reflectance spectroscopy and photoelectrochemical experiments revealed that the PtPd NCs/C3N4 photocatalyst had comparable light absorption ability and equivalent carrier separation and transfer efficiency in comparison with the PtPd NTs/C3N4 photocatalyst, which excluded the influence of these factors on shape-dependent performance. The photocatalytic hydrogen generation results indicate that the hydrogen generation rate of the PtPd NCs/C3N4 photocatalyst is 1.33 times higher than that of the PtPd NTs/C3N4 photocatalyst, demonstrating that the cubic PtPd bimetallic co-catalyst is more conducive to hydrogen generation compared to the tetrahedral PtPd bimetallic co-catalyst.