Graphdiyne(CnH2n-2) based NiS S-scheme heterojunction for efficient photocatalytic hydrogen production

Graphdiyne (g-CnH2n-2), as a novel two-dimension carbon allotrope material composed of sp- and sp2-hybrid carbon network, has been widely explored since it was synthesized for the first time by Li's group in 2010. Here, innovative progress for preparing graphdiyne by using Cu+ contained material as a catalyst is reported and the graphdiyne is coupled with NiS to produce hydrogen from photocatalytic water splitting. The composite photocatalyst NiS/GDY was prepared by simple physical mixing of graphdiyne and NiS in nanorod form, which showed excellent hydrogen production activity. In addition, the S-scheme heterojunction composed of graphdiyne and nanorod NiS effectively utilized the strongly reduced and unwanted electrons, and the addition of graphdiyne also effectively increased the absorption intensity of light. The amount of graphdiyne addition was optimized, and the best hydrogen production activity was achieved when the graphdiyne was 10 wt%. This composite catalyst deepens the application of graphdiyne in photocatalysis.