Enhanced photocatalytic H2-evolution by immobilizing CdS nanocrystals on ultrathin Co0.85Se/RGO-PEI nanosheets

We herein report a novel noble-metal-free photocatalytic H-2-production system by immobilizing CdS nanocrystals on ultrathin Co0.85Se/graphene nanosheets. The well-designed composite material was prepared by a simple solvothermal method and achieved a dramatically enhanced H-2-evolution performance when compared with other bulk counterparts. Under optimal conditions, the H-2-evolution efficiency can reach up to 17.60 mu mol mg(-1) h(-1) after 10 h of LED visible light irradiation, which is comparable to that of noble Pt nanoparticles (18.60 mu mol mg(-1) h(-1)). It is proposed that the unusual catalytic rate arises from the special nanostructure of Co0.85Se and a positive synergetic effect between Co0.85Se and graphene. The results show that the ultrathin Co0.85Se which possesses a half-metallic character is a promising noble-metal-free cocatalyst for practical photocatalytic hydrogen production application.