Visible light active graphene oxide modified Ag/Ag2O/BiPO4/Bi2WO6 for photocatalytic removal of organic pollutants and bacteria in wastewater

Abstract

Wastewater problems caused by antibiotics and bacteria contamination have become the primary environmental concern due to their harm to terrestrial organisms and health risk. To obtain the efficient removal approach of antibiotics and bacteria, visible driven advanced oxidation process by photocatalyst for the efficient removal and reducing waterborne disease was demonstrated in this study. 2D/2D GO−Ag/P/BWO heterostructure photocatalyst (GO: graphene oxide, Ag: Ag, Ag2O; P: BiPO4; BWO: Bi2WO6) were synthesized for effectively purification of antibiotics and bacteria contaminated wastewater. GO added in synthesis of BWO (1st-hydrothermal) and induced of Ag dopants (2nd-hydrothermal) of GO–Ag/P/BWO were fabricated separately and marked as GO(I)–Ag/P/BWO and GO(II)–Ag/P/BWO, characterized by different tests (FT-IR, XRD, Raman, XPS, SEM, TEM, TG, UV-VIS, PL, photocurrent density, and EIS). To testify the visible light driven photocatalytic activity of the fabricated photocatalysts, Rhodamine B (Rh B) and amoxicillin (AMX) was chosen as model emerging organic contaminants and antibiotics, respectively. While gram-negative strain Escherichia coli (E. coli) was selected as model waterborne bacteria. The results showed that GO(II)–Ag/P/BWO photocatalyst was synthesized successfully, and possessed high crystallinity, low generated electron-hole recombination rate, and high photocurrent density. The system can produce energetic active species (h+, O2− and OH), exhibiting a superior performance towards removal of Rh B, AMX and E. coli under visible light irradiation. Comparing to other reported GO modified Bi based photocatalyst, GO(II)–Ag/P/BWO had stronger photocatalytic performance in degradation of Rh B, AMX and E. coli, which indicated its high prospects for practical application in environmental wastewater treatment.