1. Abundant active sites and excellent carrier separation synergistically enhanced hydrogen generation over NiS/CdSe Schottky heterojunction photocatalysts.
- Author
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Huang, Ruixue, Li, Wenjun, Geng, Liang, Dong, Mei, Li, Yajie, Fan, Yueyan, Yang, Li, Liu, Yuan, and Han, Hongli
- Subjects
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INTERSTITIAL hydrogen generation , *X-ray photoelectron spectroscopy , *SCHOTTKY barrier , *ATOMIC hydrogen , *HYDROGEN production , *IRRADIATION - Abstract
Recently, CdSe has become a prospective material for photocatalytic hydrogen evolution. However, the photocatalytic activity of pure CdSe is still dissatisfactory due to the electron-hole pair complex and lack of active sites. In this study, CdSe/NiS Schottky heterojunction photocatalysts was successfully prepared by the hydrothermal method. Of these, CdSe is daisy-like and NiS is hydrangea-like. The photocatalytic hydrogen evolution results indicated that the photocatalytic hydrogen production rate of 25NiS/CdSe was 9399 μmol g−1 h−1 under visible light irradiation in the presence of sacrificial agents, which was 120 times higher than that of pure CdSe (78 μmol g−1 h−1). Using X-ray photoelectron spectroscopy, the catalyst's elemental makeup was revealed. Photoluminescence spectroscopy and electrochemical characterizations demonstrated that the carrier separation efficiency of NiS/CdSe was significantly improved compared with CdSe and the overpotential was lowered. This improvement can be attributed to the formation of Schottky barriers. In addition, the metal-like nature of NiS promoted charge transfer and provided additional reactive active sites for the system. This study offers novel insights for the further design of low-cost, visible-light-driven photocatalysts with high photocatalytic activity. [Display omitted] • A new and efficient CdSe/NiS photocatalyst was successfully synthesized. • NiS provides active sites for hydrogen production. • The metal-like properties of NiS and Schottky heterojunctions work together to promote charge transfer. • The hydrogen production of the optimized heterojunction is 120 times that of pure CdSe. • The optimized heterojunction exhibits the hydrogen production rate of 9399 μmol g−1 h−1. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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