2D CdS functionalized by NiS2-doped carbon nanosheets for photocatalytic H2 evolution

Two-dimensional (2D) nanosheet materials can be effective and active photocatalysts for hydrogen production. However, the thickness of a single 2D semiconductor matrix material can affect the band structure, which weakens the material for light absorption. The introduction of a carbon layer into a 2D composite photocatalyst can enhance the absorption of visible light, effectively promote charge separation, and increase active sites. In this work, we have applied a two-step (hydrothermal and liquid stripping) process to fabricate a new 2D/2D NiS2-doped carbon/CdS heterojunction photocatalyst (NiS2-C/CdS NSs). The prepared NiS2-C/CdS NSs photocatalyst has exhibited the excellent photocatalytic activity for hydrogen evolution, and the apparent quantum efficiency (AQE) of hydrogen production at 420 nm has reached 65.68%. The excellent hydrogen evolution reaction (HER) performance of NiS2-C/CdS NSs is mainly due to the interface coupling effect between NiS2-carbon nanosheets (NiS2-C NSs) and CdS nanosheets (CdS NSs), which promotes rapid charge separation and transfer so to increase the property of hydrogen evolution. This work has demonstrated a feasible procedure for constructing and modifying 2D/2D composite photocatalysts for efficient photocatalytic H2 production.