Synthesis and photocatalytic oxidation of different organic dyes by using Mn2O3/TiO2 solid solution and visible light

Abstract Mn 2 O 3 /TiO 2 solid solution was prepared from two different oxides, manganese oxide (from KMnO 4 and ethanol) and TiO 2 , these samples were characterized by BET, XRD, EDAX, SEM, FT-IR, ESR, XPS and UV–vis absorption spectroscopy. Photocatalytic activities of Mn 2 O 3 /TiO 2 powder was investigated by photooxidation of different dyes like Rhodamine B, thymol blue, methyl orange and Bromocresol green under visible light (300-W Xe lamp; λ > 420 nm). The results show that the alloy of TiO 2 with 1 mol% of Mn 2 O 3 (MNT1) exhibit photocatalytic activity 3–5 times higher than that of P25 TiO 2 for oxidation of various dyes (RB, TB, MO and BG). The average particle size and crystallite size of MNT1 were found to be 100 nm and 12 nm measured from SEM and XRD, respectively. The EPR spectra of the Mn 2 O 3 /TiO 2 samples is a sharp five-line Mn(III) component centered on g eff = 1 . 99.