Insight into the synergy of amine-modified S-scheme Cd0.5Zn0.5Se/porous g-C3N4 and noble-metal-free Ni2P for boosting photocatalytic hydrogen generation

Inadequate photogenerated carrier' separation is deemed to be the major obstacles for improving photocatalytic H-2 evolution. Here, we designed distinctive Ni2P/porous g-C3N4/Cd0.5Zn0.5Se-diethylenetriamine (Ni2P/pgC(3)N(4)/Cd0.5Zn0.5Se-D) nanojunction via an in-situ solvothermal synthesis. The cooperative effect of Cd0.5Zn0.5SeD and Ni2P can extend the visible light absorption for pg-C3N4. As a result, the ternary Ni2P/pg-C3N4/ Cd0.5Zn0.5Se-D composite exhibits high-performance H-2 evolution rate of 12627 mu mol g(-1) h(-1) using solar light, being almost 105.23 and 2.59 folds higher than those observed over Ni2P/pg-C3N4 and pg-C3N4/Cd0.5Zn0.5Se-D composite, severally. The possible mechanism is assumed that the formation of the novel Ni2P modified stepscheme (S-scheme) pg-C3N4/Cd0.5Zn0.5Se-D heterojunction which manipulated highly efficient spatial separation and directional migration of photocarriers. Moreover, DFT calculations have been performed to uncover the process of the charge transport. This work concentrates on the profound part of noble-metal-free decorated Sscheme photocatalytic system in water splitting.

Automated summary

The synthesis of the ternary Ni2P/pg-C3N4/Cd0.5Zn0.5Se-D composite has significantly improved the photocatalytic H-2 evolution rate, while also revealing the mechanism of photocarrier migration in the novel Ni2P modified S-scheme structure.