Promotion mechanism of -OH groups intercalation for NOx purification on BiOI photocatalyst

Bismuth oxyiodide (BiOI) is one of the traditional layered oxide photocatalyst that performs wide visible-light absorption band owning to appropriate band structure. Nevertheless, the photocatalytic efficiency is immensely prohibited according to the serious recombination of photogenerated charge carriers. Herein, the great challenge is addressed via a new strategy of intralayer modification by -OH groups in BiOI, which leads to the enhancement of the reactants activation capacity to promote photocatalytic activity and generate more active species. Furthermore, the analysis via combination of experimental and theoretical method revealed that the -OH groups functionalized samples could reduce the energy barriers for the main intermediate (NO2) conversion, which is easy to transformed to NO2-, thus accelerate the oxidation of NO to final products (NO3-). This study gives insight into NO oxidation on improving photocatalytic efficiency and mastering the photocatalysis reaction mechanism to curb air pollution.