Fabrication of dual Z-scheme MIL-53(Fe)/α-Bi2O3/g-C3N4 ternary composite with enhanced visible light photocatalytic performance

Z-scheme heterojunction photocatalyst can simultaneously reduce the recombination of photo-generated electron-hole pairs and preserve its outstanding redox ability during the process of photocatalytic reaction. In this study, Z-scheme MIL-53(Fe)/alpha-Bi2O3/g-C3N4 photocatalyst was successfully fabricated via an accessible method and comprehensive characterized by XRD, FT-IR, SEM, TEM, XPS, N-2 adsorption-desorption isotherms, UV-vis diffuse reflection spectroscopy and photoelectrochemical analysis. The as-obtained MIL-53(Fe)/alpha-Bi2O3/g-C3N4 composite exhibited superior photocatalytic activity for amino black 10B degradation than that of pure g-C3N4, alpha-Bi2O3, MIL-53(Fe) and alpha-Bi2O3/g-C3N4 binary composite under visible light irradiation and the photo degradation rate would achieve the maximum when the mass fraction of MIL-53(Fe) was 32% in ternary composite. The enhanced photocatalytic performance of MIL-53(Fe)/alpha-Bi2O3/g-C3N4 ternary composite could be mainly ascribed to improved visible light absorption range and the construction of an effective interfacial heterojunction driven by direct solid-state dual Z-scheme mechanism, which significantly facilitates the separation and transfer of photo-generated charge carriers. Eventually, the as-prepared ternary composite was confirmed to have prominent stability and reusability after consecutive 4 recycling run.