In situ photodeposition of metalloid Ni_2P co-catalyst on Mn_(0.5)Cd_(0.5)S for enhanced photocatalytic H_2 evolution with visible light

摘要

Developing a suitable and low-cost co-catalyst is highly desired for promoting photocatalytic water splitting of H-2 production. Herein, we adopted a simple in situ photodeposition strategy by coupling Mn0.5Cd0.5S with non-noble co-catalyst Ni2P to construct Ni2P/Mn0.5Cd0.5S composites and achieved obviously improved H-2 amount (31.83 mmol/h/ g) in visible-light region, which is nearly 2.8 times than that of pure Mn0.5Cd0.5S. Such photocatalytic performance is in a relatively superior position among MnxCd1-xS-based photocatalysts. The apparent quantum efficiency of Ni2P/Mn0.5Cd0.5S-7 composites reaches 32% at 420 nm. Through optical and photoelectrochemical measurements, a possible mechanism was proposed, it was found that the interface between metalloid Ni2P and Mn0.5Cd0.5S contacts closely, which facilitates transfer and separation of charge carriers, thus promotes the reduction of H+ to H-2. This study provides a new design of cut-price, high-efficiency photocatalyst for H-2 evolution. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.