Heterogeneous photocatalytic degradation of 4-nitrophenol by visible light responsive TiO₂-polyaniline nanocomposites

Different compositions of TiO₂-polyaniline composites were prepared via chemical oxidative polymerisation of aniline over TiO₂ nanoparticles followed by hydrothermal treatment. The prepared composites were characterised by various physicochemical techniques. From UV-VIS digital replay system (DRS) analysis, the shifts of the absorption maximum towards the visible region are indicated and transmission electron microscopy analysis showed that the particle size of TiO₂ is reduced after incorporation of polyaniline. The photocatalytic activity of visible light responsive polyaniline modified TiO₂ in the degradation of 4-nitrophenol was studied. The percentage degradation was monitored using a UV-VIS spectrophotometer. About 92% degradation was obtained with polyaniline modified TiO₂.