Enhanced hydrogen evolution via interlaced Ni3S2/MoS2 heterojunction photocatalysts with efficient interfacial contact and broadband absorption

The development of transition-metal sulfides, such as nickel sulfides (e.g., Ni3S2), as catalysts for the hydrogen evolution reaction is one potential solution to environmental pollution and energy crisis. However, its limited utilization of visible light and high recombination ratio of photoinduced electronehole pairs suppress its photocatalytic activity. The key issue in improving photocatalytic efficiency lies in fabricating a p-n heterojunctionwith efficient interfacial contact and broadband absorption. Here, we developed amethod for fabricating an interlaced Ni3S2/MoS2 heterostructure with close interfacial contact. In our fabrication approach, a porous Ni3S2 scaffold is prepared by chemical vapor deposition and a hydrothermal method is used to prepare a Ni3S2/MoS2 photocatalyst with close interfacial contact. The numerous interfaces of the interlaced Ni3S2/MoS2 heterostructures promote effective electronehole pair separation and facilitate electron transfer. Meanwhile, the hybrid Ni3S2/MoS2 nanostructures favor broadband absorption extending from 300 to 800 nm. As a result, the hybrid Ni3S2/MoS2 exhibits a remarkable rate of hydrogen evolution (540.75 mmol g(-1) h(-1)), which is 5.71 and 3.89 times greater than those of pure Ni3S2 andMoS(2), respectively, under otherwise identical conditions. The results of this work are significant for developing promising transition-metal sulfide heterostructures in the field of hydrogen evolution by photocatalyticwater splitting. (C) 2018 Elsevier B.V. All rights reserved.