Visible light-driven sliver-modified titanium dioxide / bismuth molybdenum oxide with rapid interfacial charge-transfer for dual highly efficient photocatalytic degradation and disinfection

Abstract

Enhancing interfacial charge transfer is a promising approach to improve the efficiency of photocatalysts. This research effectively exploited an Ag-modified Z-scheme TiO2/Bi2MoO6 heterojunction for photocatalytic degradation and disinfection under visible light. The catalyst was fabricated using simple hydrothermal and photo-deposition methods, and the characterization outcomes revealed that a built-in electric field (BIEF) was generated in the TiO2/Bi2MoO6 heterojunctions, which significantly promotes the separation of photogenerated carriers and increases light absorption efficiency. Besides, the theoretical calculation demonstrated that electron migration between TiO2 and Ag resulted in a strong coupling on the surface, which serves as the foundation for driving photoelectric charge transfer. Furthermore, the TiO2/Bi2MoO6/Ag-45 displayed 459% and 512% higher degradation efficiency of tetracycline hydrochloride (TC-HCl) and ciprofloxacin (CIP) after 100 min compared to pristine TiO2. Moreover, the complexes wholly inactivated gram-negative Escherichia coli (E. coli) and significantly inhibited the growth of gram-positive Staphylococcus albus (S. albus) after 200 min. Additionally, we have deduced the potential degradation pathways of TC-HCl and CIP and photocatalytic mechanisms. The research results provide an idea to solve the problems of limited light absorption range and rapid carrier combination speed of traditional photocatalytic materials, which is expected to be applied in the field of actual wastewater treatment.