construction of surface oxygen vacancies on N/TiO for promoting visible light photocatalytic H evolution

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2024-11, Vol.12 (43), p.175-1751
• Main Authors: Shen, Yuandong, Yang, Nan, Wang, Ke, Xiao, Bin, He, Yijun, Qiu, Zhishi, Zhou, Tong, Zhan, Weijie, Hu, Rui, Zhang, Genlin, Zhang, Jin, Zhu, Zhongqi, Liu, Feng, Cui, Hao, Liu, Qingju
• Format: Article
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d4tc03098b

Realizing photocatalytic hydrogen evolution under visible light still has many challenges, especially due the contradiction between the dependence of doping on high temperature and the passivation of catalytic active sites caused by high temperature. Herein, a simple method of mixed sintering of thiourea and NH 2 -MIL-125(Ti) was adopted to achieve both N doping and surface O v in situ construction on TiO 2 , significantly improving the visible light catalytic hydrogen evolution performance. Experiments confirm that N doping can regulate the band structure and enhance the light absorption range of TiO 2 , while the improvement of surface photocatalytic activity mainly depends on surface defects. Experimental and theoretical studies show that N doping regulates the electron distribution of TiO 2 and forms a photogenerated electron transport channel, which promotes the migration of photogenerated electrons. O V can capture photogenerated electrons and prolong the lifetime of electrons. The H absorption and desorption equilibrium on the catalyst surface can be optimized by O V for promoting hydrogen evolution. Consequently, under irradiation of light with 365, 385, 400 and 420 nm wavelengths, the average hydrogen evolution rates of the best sample are 14 700, 4850, 720 and 87 μmol g −1 h −1 , respectively. This work provides ideas for the design and development of photocatalysts for visible light photocatalytic hydrogen evolution. A simple method of mixed sintering of thiourea and NH 2 -MIL-125(Ti) is adopted to obtain N-doped TiO 2 with abundant surface O V , which significantly improves the photocatalytic performance of TiO 2 under visible light.