Cellulose as Sacrificial Biomass for Photocatalytic Hydrogen Evolution over One‐dimensional CdS Loaded with NiS2 as a Cocatalyst

Abstract

AbstractNiS2 nanoparticles (NPs)‐modified CdS nanowires (NWs) (NiS2/CdS) with varying amount of NiS2 were synthesized via a two‐step approach and characterized for sustainable hydrogen evolution. They showed much higher activity than pristine CdS NWs or NiS2 NPs, with the optimal hydrogen production rate reaching 14.49 mmol⋅h−1⋅g−1 for 40%‐NiS2/CdS with lactic acid as sacrificial agent. Under optimal conditions, hydrogen generation rate of 52.88 μmol⋅h−1⋅g−1 was achieved using single cellulose as sacrificial agent. Photoelectrochemical (PEC) properties of the NiS2/CdS nanocomposites were investigated to gain a better understanding of the mechanism behind the enhanced photocatalytic hydrogen evolution reaction (HER) activity. Furthermore, ultrafast transient absorption (TA) spectroscopy was also employed to investigate the charge carrier dynamics, revealing an exciton lifetime approximately four times shorter in 40%‐NiS2/CdS nanocomposite compared to pristine CdS NWs. These results suggest efficient charge transfer from CdS to NiS2. A possible mechanism for enhanced hydrogen production over NiS2/CdS nanocomposite is proposed.