Dual electric fields induced synergistic photocatalytic inactivation: Unveiling mechanisms and phenomena of enhanced performance

Abstract

Photocatalytic inactivation, emerging as a novel bactericidal technique, is gaining increasing attention. While oxygen vacancies (OVs) and heterogeneous junction structures have been extensively investigated to enhance photocatalytic performance, the synergistic effect between the two remains largely unexplored. In this study, a Bi₂S₃@BiOCl-OV heterojunction structure enriched with oxygen vacancies as a promising photocatalyst was developed. Bi₂S₃@BiOCl-OV effectively improved photocatalytic properties due to the presence of oxygen vacancies and the unique structure of Z-type heterojunction. Further mechanism investigation shows that the unique heterojunction structure can induce the formation of internal electric field, the existence of oxygen vacancies can promote the generation of micro local electric field, and effectively promote the charge redistribution under the action of dual-electric field. Simultaneously, O₂ and H₂O in the system are adsorbed by oxygen vacancies, and are activated by electrons to form the reactive oxygen species, thereby achieving the goal of killing microorganisms.