Understanding Aerobic Nitrogen Photooxidation on Titania through In Situ Time‐Resolved Spectroscopy
Shuai Zhang, Yunxuan Zhao, Yingxuan Miao, Yanjun Xu, Jingrun Ran, Zhuan Wang, Yuxiang Weng, Tierui Zhang
Abstract
Abstract Nitrate is an important raw material for chemical fertilizers, but it is industrially manufactured in multiple steps at high temperature and pressure, urgently motivating the design of a green and sustainable strategy for nitrate production. We report the photosynthesis of nitrate from N 2 and O 2 on commercial TiO 2 in a flow reactor under ambient conditions. The TiO 2 photocatalyst offered a high nitrate yield of 1.85 μmol h −1 as well as a solar‐to‐nitrate energy conversion efficiency up to 0.13 %. We combined reactivity and in situ Fourier transform infrared spectroscopy to elucidate the mechanism of nitrate formation and unveil the special role of O 2 in N≡N bond dissociation. The mechanistic insight into charge‐involved N 2 oxidation was further demonstrated by in situ transient absorption spectroscopy and electron paramagnetic resonance. This work exhibits the mechanistic origin of N 2 photooxidation and initiates a potential method for triggering inert catalytic reactions.