Fabrication of direct Z-scheme heterojunction between Zn0.5Cd0.5S and N-rich graphite carbon nitride for boosted H2 production

In this work, a novel direct Z-scheme g-C3N5/Zn0.5Cd0.5S (CN/ZCS) heterojunction was successfully synthesized. Furthermore, its photocatalytic activity for hydrogen production was also investigated, whose photoluminescence spectrum revealed the charge transfer procedure of g-C3N5 and ZCS. Moreover, the optimized hydrogen production rate of ZCS with 15 wt% of g-C3N5 (15% CN/ZCS) was about 142.8 mmol/h/g and quantum efficiency (Q.E.) was circa 33.7% under 420 nm monochromatic light. Compared with the pure ZCS and ZCS with 2 wt% of Pt, the 15% CN/ZCS composite exhibited considerable improved hydrogen production rate, which was about 20 times and 7 times, respectively. The formation of CN/ZCS composite resulted in faster separation of the photogenerated electron-hole pairs. Our work may supply valuable data for the application of g-C3N5 on photocatalysis.