MOF-templated in situ fabrication of surface-modified Ni/graphitic carbon nitride with enhanced photocatalytic hydrogen evolution

The fabrication of noble-metal-free and low-cost photocatalysts with high efficiency has been under increasing demand for solar energy usage and conversion. In this work, a series of surface-modified Ni/graphitic carbon nitride (g-C3N4) photocatalysts derived from metal-organic frameworks (MOFs) were synthesized by the in situ pyrolysis of Ni-based benzenedicarboxylic acid Ni-2(BDC)(2) in the presence of graphitic carbon nitride under Ar protection. The as-prepared samples displayed highly efficient H-2 evolution under visible-light irradiation, with a maximum H-2 production rate of 2989.5 mu mol g(-1) h(-1), which was about 22.1 times higher than the value of carbon nitride (135.2 mu mol g(-1) h(-1)). This exceptionally enhanced photocatalytic activity originated from the tight bonding between the Ni-based cocatalyst and g-C3N4 as well as fast and efficient electron transfer with the help of conductive carbon loaded on the surface of the Ni species during Ni-2(BDC)(2) pyrolysis.