Suspended and polycaprolactone immobilized Ag @TiO2/polyaniline nanocomposites for water disinfection and endotoxin degradation by visible and solar light-mediated photocatalysis

Abstract

In the present study, water contaminated with Escherichia coli (E. coli) cells was photocataytically disinfected using Ag core-TiO2 shell/Polyaniline nanocomposite (Ag@TiO2/PANI) under visible light irradiation. Ag@TiO2/PANI containing 13 weight % of Ag@TiO2 was found to offer maximum disinfection activity. Band gap energy of Ag@TiO2/PANI was found to be 2.58 eV. Ag@TiO2/PANI nanocomposites were efficient in water disinfection in their suspended and immobilized form. Rate of disinfection with Ag@TiO2/PANI was faster than that with Ag@TiO2 nanoparticles. Water containing 50 × 108 CFU/mL cells was completely disinfected within 120 min with 1 g/L Ag@TiO2/PANI nanocomposite. Simultaneous disinfection and endotoxins degradation were achieved. The photocatalytic disinfection of water and endotoxin degradation using Ag@TiO2/PANI nanocomposite under visible light irradiation followed second order kinetics. The nanocomposite also exhibited a good solar photocatalytic activity. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.