Noble-metal-free ternary CN–ZCS–NiS nanocomposites for enhanced solar photocatalytic H2-production activity

Abstract

Photocatalytic hydrogen production from water using a noble-metal-free catalyst has aroused tremendous and interdisciplinary attention. In this work, we report a series of original noble-metal-free ternary nanocomposites of C₃N₄-Zn_0.5Cd_0.5S heterojunctions loaded with NiS by a precipitation hydrothermal method. They were characterized by XRD, TEM, SEM-EDS, UV-vis, XPS, PL spectra, and transient photocurrent response measurements. The facts proved that they were efficient and stable photocatalysts to enhance the hydrogen production activity prepared by the precipitation hydrothermal method. Among these photocatalysts, C₃N₄-Zn_0.5Cd_0.5S-1% NiS showed excellent photocatalytic performance with a H₂-production rate of 53.190 mmol g⁻¹ h⁻¹ which is 405 times higher than the pure CN. The high catalytic activity was attributed to the synergistic effect of the NiS cocatalyst and the nanoheterojunctions between ZCS nanoparticles and 2D CN nanosheets, which were propitious to accelerate charge transfer, promote the separation of photogenerated electron–hole pairs and expedite the surface H₂-evolution kinetics.