Three-Dimensional Bi 5 O 7 I Photocatalysts for Efficient Removal of NO in Air Under Visible Light

In this study, we report a flower-like Bi5O7I photocatalyst with a 41% gaseous nitride oxide (NO) removal efficiency under visible light through the in situ thermal treatment of the hierarchical architecture BiOI synthesized using a facile hydrothermal process. The UV–Vis diffuse reflectance spectroscopy and photocurrent experiments showed that the absorption band edge and photo-induced electron–hole pairs separation efficiency of Bi5O7I were negative than that of BiOI, whereas the as-prepared Bi5O7I exhibited excellent and stable visible light photocatalytic performance for NO removal as compared with original BiOI and P25. The results of electron spin resonance spectroscopy and density functional theory calculations suggested that the prominent visible light photocatalytic activity of obtained Bi5O7I has been attributed to the proper electron band structure which oxidizes the O2 molecule to · OH radicals with two electrons in the conduction band. © 2017, Institute of Earth Environment, Chinese Academy Sciences.