Photocatalytic degradation of rhodamine-B over mono- & bi-metallic TiO2 catalysts

Abstract

In this study, mono- (0.5 wt% and 1 wt% Ag) and bi-metallic (Ag-Cu) titania catalysts of different loadings were prepared using ultrasound assisted sol–gel synthesis process and subsequently tested for photocatalytic activity using the degradation of Rhodamine-B. The catalysts were characterized by using FTIR, FESEM, photoluminescence, XRD and diffuse reflectance spectroscopy for band-gap analysis. SEM images showed that all the synthesized catalysts were irregular in shape compared to the P25 catalyst with large crystallite sizes. XRD analysis showed presence of mostly anatase phase for all the catalysts. Maximum photocatalytic activity was observed with monometallic silver doped catalyst (1 wt% Ag doped on TiO2). It was observed that the degradation of Rhodamine-B dye followed first order reaction kinetics with a rate constant of 3.6 × 10−2 min−1. Overall, the work demonstrated improved synthesis method for photocatalyst with successful degradation of rhodamine B dye during the actual application.