LED-driven sulfamethazine removal and bacterial disinfection by a novel photocatalytic textile impregnated with oxygen vacancy-rich BiO2-x/g-C3N4 hybrid

Oxygen vacancies (OVs) and heterostructures of photocatalysts play crucial roles in photocatalysis driven by visible light. In this study, a novel photocatalytic textile was prepared by spraying heterostructures of OVs-rich bismuth oxide (BiO2-x) and urea-derived graphitic carbon nitride (UCN) on amine group-modified poly(acrylonitrile) nonwoven textile (APAN), and then studied for sulfamethazine (SMT) removal and bacterial (S. aureus) disinfection under irradiation of energy-efficient white light emitting diodes (LEDs). The optimal BiO2-x, prepared within a much shorter time (i.e. 1 h), was actually a ternary mixture of NaBiO3-Bi2O3-BiO2-x with rich OVs rather than pure BiO2-x. Incorporation of UCN could help redistribute electrons and induce formation of more OVs, thereby improve the photocatalytic activity of the BU-0.2 hybrid (i.e. mass ratio of BiO2-x/UCN = 1:0.2). The BU-0.2 could use full-spectrum white light (i.e. 380-760 nm) to achieve superior SMT removal in a wide pH range (pH 5.0-9.0) and in the co-presence of common water constituents. The enhanced photocatalytic performance of BU-0.2 was attributed to the formation of OVs and heterostructure, which could broaden light absorption, help charges separation, and favor adsorption and activation of molecular O2. Detection of reactive species demonstrated that 1O2 and holes were the dominant factors responsible for SMT removal. Spraying deposition of BU-0.2 on APAN could endow the resultant textile (i.e. APAN-BU-0.2) with excellent photocatalytic activity for SMT removal and bacterial disinfection under LED white light irradiation. The as-prepared photocatalysts showed promising application prospects in purification of emerging pollutants utilizing LED white light.