Materials Research Bulletin, Vol.106, 388-395, 2018
Photocatalytic enhancement of immobilized TiO2-polyaniline bilayer (TiO2-PBL) system for decolorization of methyl orange dye
Immobilized TiO2-polyaniline (PANI) bilayer (TiO2-PBL) was fabricated on a glass plate for decolorization of methyl orange (MO). The thickness of TiO2-PBL was 25.55 gm with the ratio of 0.62:0.38 for TiO2 to PANI layer. It was observed that the TiO2-PBL system emitted less photoluminescence (PL) intensity than the TiO2 monolayer corresponding to better (OH)-O-center dot radicals production with reduced band gap energy. The removal of MO from the solution after 90 min of treatment was 97% by TiO2-PBL and 53% by TiO2 monolayer which indicates the efficacy of the former system due to the synergistic photocatalytic-adsorption processes. The effect of pre-washing (photoetching) of TiO2-PBL plate was pronounced as better removal efficiency of MO was observed for ten cycles under UV-vis and visible light irradiations. The results showed that the TiO2-PBL system has visible light active properties, reduces the recombination of photogenerated active species and enhances the photo catalytic oxidation of MO.