Insight into the mechanism of photocatalytic degradation of gaseous o-dichlorobenzene over flower-type V2O5 hollow spheres

Abstract

This work aims to explore the mechanism of photocatalytic degradation of gaseous 1,2-dichlorobenzene (o-DCB) over vanadium pentoxide (V₂O₅) hollow spheres. To this end, flower-type V₂O₅ hollow microspheres with diameters of about 700–800 nm were obtained with the assistance of carbon-sphere templates, and then tested in the photodegradation of o-DCB under visible light (λ > 400 nm). Due to its strong adsorption capacity and large specific surface area, the V₂O₅ hollow structure showed high photocatalytic activity in the degradation of gaseous o-DCB under visible light. Furthermore, the o-DCB degradation mechanism was investigated by using in situ Fourier transform infrared (FTIR) spectroscopy, and the intermediates, such as o-benzoquinone-type and organic acid species, and final products (CO₂ and H₂O) were also confirmed. Then, the reaction pathways over V₂O₅ were proposed. The outstanding performance indicated that the photocatalysts could be applied to air purification for Chlorinated Volatile Organic Compound (Cl–VOC) removal.