Cellulose as Sacrificial Biomass for Photocatalytic Hydrogen Evolution over One‐dimensional CdS Loaded with NiS <sub>2</sub> as a Cocatalyst
Chunhe Li, Sara Bonabi Naghadeh, Liping Guo, Ke Xu, Jin Z. Zhang, Hongmei Wang
Abstract
Abstract NiS 2 nanoparticles (NPs)‐modified CdS nanowires (NWs) (NiS 2 /CdS) with varying amount of NiS 2 were synthesized via a two‐step approach and characterized for sustainable hydrogen evolution. They showed much higher activity than pristine CdS NWs or NiS 2 NPs, with the optimal hydrogen production rate reaching 14.49 mmol⋅h −1 ⋅g −1 for 40%‐NiS 2 /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 NiS 2 /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%‐NiS 2 /CdS nanocomposite compared to pristine CdS NWs. These results suggest efficient charge transfer from CdS to NiS 2 . A possible mechanism for enhanced hydrogen production over NiS 2 /CdS nanocomposite is proposed.