Photoinduced pyrene degradation in contaminated soils by polyaniline coated photocatalysts

Abstract

Polyaniline (PA) coated TiO₂ and ZnO nanoparticles have been used to improve the photocatalytic efficiency of pyrene degradation in soil samples. The interfacial polymerization method is used to prepare the polyaniline coated ZnO and TiO₂ nanocomposites, which are characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The SEM images and the SPSS analysis demonstrate the particle size distribution in the range of 100–400 nm. The surface charge of the polyaniline coated TiO₂ and ZnO nanocomposites are found to be 19.5 and 21.2 mV, respectively. The pyrene removal efficiency is more than 95% on the polymer coated photocatalysts surface. The high degradation efficiency of the polyaniline coated ZnO and TiO₂ nanocomposites is probably due to the high capacity of polyaniline for the adsorption of pollutants from the contaminated soils; the semiconducting behavior is reflected in the chain structure of the polymer under both ultraviolet and visible irradiation. Enhanced photocatalytic activity for degradation of pyrene under UV and visible light, is possibly due to the synergistic effect of PA and NPs.