Boron doped graphitic carbon nitride dots dispersed on graphitic carbon nitride/graphene hybrid nanosheets as high performance photocatalysts for hydrogen evolution reaction

Abstract

Ternary hybrid photocatalysts have been prepared consisting Boron doped graphitic carbon nitride dots (BCNDs) dispersed on high-surface-area graphitic carbon nitride/ reduced graphene oxide (g-C3N4/rGO) hybrid nanosheets. The overall procedure was developed in four stages. First, g-C3N4 nanosheets with positive charge and graphene oxide (GO) nanosheets with negative charge were prepared by treating bulk g-C3N4 in nitric acid and using the modified Hummer’s method, respectively. Second, mixing the two solution with opposite charge, g-C3N4/rGO hybrid nanosheets will form under the driving of electrostatic gravity. Next, the BCNDs were introduced onto the surface of g-C3N4/rGO hybrid nanosheets through hydrothermal process. Finally, the resulting ternary hybrid photocatalysts were tested for photocatalytic hydrogen evolution reaction. The ternary photocatalysts exhibited a high hydrogen evolution rate of 741.4 µmol·h−1·g−1 and an apparent quantum efficiency of 19.0% at 420 nm. Compared with binary hybrid photocatalysts, the experiments results indicate that ternary photocatalysts can efficiently suppress electron-hole pairs recombination and improve the photocatalytic performance.