Abstract
Diethyl phthalate (DEP), a representative phthalate ester known for its environmental persistence and endocrine- disrupting effects, poses a significant challenge in wastewater treatment. To address this, a dielectric barrier discharge (DBD) plasma system coupled with solvent-regulated BiOBr catalysts was developed for efficient DEP degradation. Following catalyst screening and process parameter optimization, the system achieved approximately 19 % higher degradation efficiency compared to the non-catalytic plasma process. The layered structure and favorable band alignment of BiOBr facilitated charge transfer and oxygen activation under plasma excitation, resulting in a pronounced plasma-catalyst synergy that accelerated oxidative decomposition. Electronic- structure analysis further revealed that the Bi-O-Br orbital configuration promoted the continuous generation of reactive oxygen species. These findings elucidate the intrinsic coupling mechanism between plasma discharge and catalyst surface reactions, offering new insights for designing efficient plasma-assisted systems for organic wastewater purification.