Synergetic catalysis enhancement between H2O2 and TiO2 with single-electron-trapped oxygen vacancy
Zhijiao Wu, Kai Guo, Shuang Cao, Wenqing Yao, Lingyu Piao
Abstract
The TIO 2 -H 2 O 2 system possesses excellent oxidation activity even under dark conditions. However, the mechanism of this process is unclear and inconsistent. In this work, the binary component system containing TiO 2 nanoparticles (NPs) with single electron-trapped oxygen vacancy (SETOV, Vo) and H 2 O 2 exhibit excellent oxidative performance for tetracycline, RhB, and MO even without light irradiation. We systematically investigated the mechanism for the high activity of the TIO 2 -H 2 O 2 under dark condition. Reactive oxygen species (ROS) induced from H 2 O 2 play a significant role in improving the catalytic degradation activities. X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) results firstly confirm that H 2 O 2 is primarily activated by SETOVs derived from the TiO 2 NPs through direct contribution of electrons, producing both 02-/·AOOH and ·OH, which are responsible for the excellent reactivity of TiO 2 -H 2 O 2 system. This work not only provides a new perspective on the role of SETOVs playing in the H 2 O 2 activation process, but also expands the application of TiO 2 in environmental conservation.