We herein report a novel noble-metal-free photocatalytic H2-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 H2-evolution performance when compared with other bulk counterparts. Under optimal conditions, the H2-evolution efficiency can reach up to 17.60 μmol mg?1 h?1 after 10 h of LED visible light irradiation, which is comparable to that of noble Pt nanoparticles (18.60 μmol 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.

J. Mater. Chem. A, 2015

(a) TEM and (b) HRTEM images, (c) EDXS spectrum, and (d) SAED of Co_0.85Se/RGO–PEI.