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

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 (lambda > 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.