Novel noble-metal free S/Ni12P5/Cd0.5Zn0.5S composite with enhanced H2 evolution activity under visible light

Abstract

Constructing composite photocatalyst is an efficient way to realize the application of photocatalysis owing to the fast separation of photocarriers. In this report, we constructed a novel ternary noble-metal free S/Ni12P5/Cd0.5Zn0.5S (S/Ni12P5/CZS) composite which displayed much higher activity than binary Ni12P5/CZS, S/CZS and especially CZS solid solution for H2 generation under visible light illumination (λ ≥ 420 nm). 15% S/Ni12P5/CZS showed the highest activity of H2 production (525.5 μmol h−1) among all the samples due to the optimal separating efficiency of photocarriers, and its apparent quantum efficiency is 4.37% at 420 nm. In the photocatalytic process, the photogenerated electrons of CZS solid solution quickly moved to elemental S through Ni12P5 as solid electron transfer mediator, resulting in high separation efficiency of photocarriers and outstanding activity of H2 production over S/Ni12P5/CZS. Moreover, S/Ni12P5/CZS presented excellent stability after 10 runs recycling experiment. The significant finding of this paper provides new strategy to rationally design composite photocatalyst for efficiently splitting water to generate clean energy H2.