g-C3N4-SiC-Pt for Enhanced Photocatalytic H-2 Production from Water under Visible Light Irradiation

摘要

Graphite carbon nitride (g-C3N4) and SiC have drawn increasing attention for application in visible light photocatalytic hydrogen evolution by water splitting due to their unique band structure and high physicochemical stability. Herein, a g-C3N4-SiC heterojunction with loaded noble metal is constructed. The g-C3N4-SiC-Pt composite photocatalysts are successfully prepared by the combination method of bio-reduction, sol deposition, and calcination. The layers of g-C3N4 are thinned, and both SiC and Pt nanoparticles are simultaneously tightly bound to g-C3N4 by calcination during the preparation of g-C3N4-SiC-Pt. The heterojunction formed at the interface of SiC and g-C3N4 enhances the separation efficiency of the photogenerated electron-hole pairs. These composite photocatalysts achieve a high hydrogen evolution rate of 595.3 mu mol h(-1) g(-1) with 1 wt% of deposited Pt, which is 3.7- and 2.07-fold higher than those of g-C3N4-bulk and g-C3N4-SiC under visible light irradiation with a quantum efficiency of 2.76% at 420 nm, respectively.