C,N Doped TiO 2 Nanoparticles with Abundant Surface Ti 3+ and Oxygen Vacancies for Visible-Light Photocatalytic Hydrogen Production

作者：Ke Wang, Nan Yang, Bin Xiao, Yuandong Shen, Baoye Zi, Zhishi Qiu, Tong Zhou, Rui Hu, Weijie Zhan, Guoyang Qiu, Changyu Duan, Feng Liu, Zhongqi Zhu, Jin Zhang, Qingju Liu · 发表于：ACS Applied Nano Materials · 年份：2024 · DOI：10.1021/acsanm.4c03823 · 被引用次数：35 · 研究领域：Advanced Photocatalysis Techniques、TiO2 Photocatalysis and Solar Cells、Copper-based nanomaterials and applications

Broadening the light absorption range and enhancing the surface activity of photocatalysts represent a pressing necessity for realizing visible-light photocatalytic hydrogen production. Here, the sol–gel method and microwave hydrothermal method were used to obtain C and N codoped (C,N codoped) TiO 2 nanoparticles, which significantly improved their photocatalytic hydrogen production performance under visible light. The C,N codoping introduces impurity energy levels, which narrows the band gap and promotes visible-light absorption. More importantly, the C,N codoping also induces abundant surface O V and Ti 3+ . These defects can capture the photogenerated electrons, which promotes the separation of photogenerated carriers and enables electron transfer to the surface for the reduction of H*. Density functional theory (DFT) calculations confirm that the O V and Ti 3+ can significantly reduce the Gibbs free energy of H* adsorption and desorption on the C,N/TiO 2 nanoparticles surface, promoting the kinetics of hydrogen evolution. Impressively, the optimal C,N/TiO 2 can achieve an average hydrogen evolution rate of 610 μmol g –1 h –1 under visible light (λ = 400 nm) and an apparent quantum yield of 1.05%, while pure TiO 2 has no performance under visible light irradiation. This work will inspire the development and study of visible-light photocatalysts for photocatalytic hydrogen production.