One-step synthesis of Bi4Ti3O12/Bi2O3/Bi12TiO20 spherical ternary heterojunctions with enhanced photocatalytic properties via sol-gel method

In this paper, the Bi4Ti3O12/Bi2O3/Bi12TiO20 (BTO) spherical ternary heterojunction composite was successfully prepared by a simple sol-gel method. The phase, morphology and optical properties of the catalyst were studied by XRD, SEM, FT-IR, UV-vis DRS and PL. The catalyst exhibits excellent catalytic performance under visible light irradiation for remove of 17 beta-Estradiol (E2). The degradation efficiency of E2 could approach 100% using Bi4Ti3O12/Bi2O3/Bi12TiO20 (the molar ratio of Bi: Ti = 6:1) as photocatalyst under visible light irradiation for 100 min. The removal rate of 6-BTO catalyst was significantly better than P25 (38.9%) and pure Bi2O3 (83.7%). The active species and band gaps of photocatalysts were studied by the capture experiments of active substances and UV-Vis diffuse reflectance spectra, and the possible photocatalytic mechanism was speculated.