Preparation and Photocatalytic Activity of Ag Modified Ti-Doped-Bi₂O₃Photocatalyst

Abstract

Ti doped Bi 2 O 3 (TDB) and Ag ion modified Ti doped Bi 2 O 3 (Ag@TDB) photocatalysts were prepared by framework replacement synthesis method with different Ag loadings (0.05, 0.3, 0.75, and 1.0 mol/L AgNO 3 ). The structural properties of the prepared catalysts were studied by scanning electron microscope (SEM), X-ray diffraction (XRD), BET surface area, and UV/Vis diffuse reflectance (DRS). The XRD spectra of the Ti doped Bi 2 O 3 calcined at 650°C showed the diffraction peaks of a mixture of Bi 12 TiO 20 and Bi 4 Ti 3 O 12 , with bits of mixed crystallite consisting of TiO 2 and B 2 O 3 . A high blue shift in the range 650–550 nm was detected in the DRS band. This blue shift increased with the decreasing Ag content. The photocatalytic activities of the catalysts were evaluated for the degradation of crystal violet (CV) under UV light irradiation. The results indicated that the degradation rate of CV by using 1.0 mol/L AgNO 3 doped bismuth titanate composite photocatalyst (1.0 Ag@TDB) was 1.9 times higher than that by using the bare Ti doped Bi 2 O 3 photocatalyst. The higher activity of Ag@TDB is due to the enhancement of electron-hole pair separation by the electron trapping of silver particles.