AgBr and GO co-decorated g-C3N4/Ag2WO4 composite for enhanced photocatalytic activity of contaminants degradation

A novel AgBr and GO co-decorated g-C 3 N 4 /Ag 2 WO 4 (g-C 3 N 4 /Ag 2 WO 4 /AgBr/GO) composite was successfully fabricated by hexadecyl trimethyl ammonium bromide (CTAB)-assisted co-deposition of AgBr and GO onto g-C 3 N 4 /Ag 2 WO 4 composite. The as-prepared composites were characterized by XRD, SEM, TEM, FT-IR, BET, XPS, UV–vis diffuse reflectance spectra (DRS), photoluminescence spectra (PL), and electrochemistry impedance spectroscopy (EIS). The photocatalytic efficiency for tetracycline (TC) degradation over the as-prepared g-C 3 N 4 /Ag 2 WO 4 /AgBr/GO composite is 91.64% within 100 min simulated sunlight irradiation, which is nearly 2.59 and 5.25-folds greater than those of the g-C 3 N 4 /Ag 2 WO 4 and g-C 3 N 4 samples. The enhancement of photocatalytic performance is mainly ascribed to the introduction of AgBr and GO, which serve as photosensitizer and electron acceptor, respectively, confirmed by the results of DRS, PL, and EIS. The active species trapping experiments confirmed that O 2 − and h + are the dominant reactive species responsible for TC degradation. Furthermore, a reasonable n-n heterojunction-based photocatalytic mechanism for the g-C 3 N 4 /Ag 2 WO 4 /AgBr/GO composite was proposed.