Optimizing the Electronic Structure of BiOBr Nanosheets\nvia Combined Ba Doping and Oxygen Vacancies for Promoted Photocatalysis

Abstract

The\npromotion of BiOBr via simultaneous alkaline earth metal (Ba)\ndoping and massive oxygen vacancies (OVs) was for the first time investigated\ntoward the photocatalytic removal of NO in air. The adsorption of\nNO and the generation of reactive oxygen species have been significantly\nenhanced with the synergistic effect of the Ba dopant and OVs, as\nevidenced by the highly combined experimental characterization and\ntheoretical simulations, which is beneficial to optimizing the performance\nof photocatalytic NO removal. The removal rate on Ba-doped BiOBr with\nOVs is ∼10 times higher than that on the pristine BiOBr after\n30 min of visible-light irradiation. Significantly, <i>in situ</i> DRIFTS spectra and density functional theory calculations revealed\nthat the NO⁺ intermediate forming on the Ba-doped BiOBr\nwith OVs efficiently reduces the energy barrier and inhibits the generation\nof toxic byproducts, contributing to the optimization of the reaction\nprocess. The findings of this work go deep into the understanding\nof the synergistic effect of alkaline earth metal doping and OVs for\nelevating the photocatalysis efficiency.