Coralline-like Ni2P decorated novel tetrapod-bundle Cd0.9Zn0.1S ZB/WZ homojunctions for highly efficient visible-light photocatalytic hydrogen evolution

Abstract

In this study, Ni2P-Cd0.9Zn0.1S (NPCZS) composites were synthesized by coupling tetrapod bundle Cd0.9Zn0.1S (CZS) and coralline-like Ni2P (NP) via a simple calcination method. CZS shows outstanding activity in photocatalytic hydrogen evolution (1.31 mmol h−1), owing to its unique morphology and heterophase homojunctions (ZB/WZ), which accelerate the separation and transfer of photogenerated charges. After coupling with NP, the photoactivity of NPCZS was enhanced, and the maximum hydrogen evolution rate of 1.88 mmol h−1 was reached at a NP content of 12 wt%, which was 1.43 times higher than that of pure CZS. The experimental results of the photocatalytic activity, viz. photoluminescence spectra, surface photovoltage spectra, and electrochemical test showed that the enhanced photoactivity of NPCZS should be attributed to the synergistic effects of the novel tetrapod-bundle morphology, heterophase homojunctions, and decoration of the NP co-catalyst. Moreover, the as-prepared NPCZS composites exhibited excellent photostability and recyclability. Herein, we propose a possible mechanism for the enhanced photocatalytic activity.