Dong Hao, Ji Yekun, Shao Qi, Hu Xueyu, Zhang Jian, Yao Xiaohong, Long Chao
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Quanzhou Institute for Environmental Protection Industry, Nanjing University, Beifeng Road, Quanzhou 362000, China.
Sci Total Environ. 2024 May 10;924:171521. doi: 10.1016/j.scitotenv.2024.171521. Epub 2024 Mar 7.
The catalytic activity of TiO is contingent upon its crystal structure and the optoelectronic properties associated with defects. In this study, a one-step method was used to synthesize TiO with a spatial interface of rutile/anatase phases, and a simple thermal annealing process was applied to optimize the amorphous regions and oxygen vacancies at the interface between the rutile and anatase phases of TiO. High-resolution transmission electron microscopy (HRTEM) elucidates the evolution process of the amorphous domain at the interface, skillfully introducing oxygen vacancies at the heterojunction interface by modulating the amorphous domain. The obtained photocatalyst (TiO-350 °C) after annealing exhibits an optimal interface structure, with its photocatalytic activity and stability in degrading toluene far superior to P25. Photocurrent and photoluminescence (PL) measurements affirm that the existence of interfacial oxygen vacancies heightens the efficiency of electron transfer at the interface, while surface oxygen vacancies significantly enhance the stability and mineralization rate of toluene degradation. The improved photocatalytic properties were attributed to the combined effects of surface/interface oxygen vacancies and spatial interface heterojunctions. The one-step synthesis method developed in this work provides a novel perspective on combining spatially interfaced anatase/rutile phases with surface/interfacial oxygen vacancies.
TiO的催化活性取决于其晶体结构以及与缺陷相关的光电特性。在本研究中，采用一步法合成了具有金红石/锐钛矿相空间界面的TiO，并通过简单的热退火工艺优化了TiO中金红石相和锐钛矿相界面处的非晶区域和氧空位。高分辨率透射电子显微镜（HRTEM）阐明了界面处非晶域的演化过程，通过调节非晶域巧妙地在异质结界面引入了氧空位。退火后得到的光催化剂（TiO-350 °C）呈现出最佳的界面结构，其在降解甲苯方面的光催化活性和稳定性远优于P25。光电流和光致发光（PL）测量证实，界面氧空位的存在提高了界面处电子转移的效率，而表面氧空位显著提高了甲苯降解的稳定性和矿化率。光催化性能的改善归因于表面/界面氧空位和空间界面异质结的综合作用。本工作中开发的一步合成方法为将空间界面的锐钛矿/金红石相与表面/界面氧空位相结合提供了新的视角。
