Recycling and photodegradation processes of organic hazardous materials on polyaniline-titanium dioxide quantum dots catalyst

A photo-catalyst with conducting polymers doped with titanium dioxide, known as TiO₂ quantum dots (TiO₂ QDs), has a high efficiency for photocatalytic usage. The organic hue methyl orange was broken down in the current study using polyaniline (PANI) and polyaniline titanium dioxide quantum dots (PANI-TiO₂ QDs) polymers. PANI and PANI-TiO₂ QDs have been produced by chemical oxidative polymerization in an aqueous solution. By characterization of PANI-TiO₂ QDs nanocomposites using ultraviolet–visible (UV–vis), Fourier transform infrared (FTIR), and X-ray powder diffraction (XRD), it was demonstrated that the chemical structure of polymer composites had not changed after being doped with TiO₂ QDs. To determine the form, size, surface area, and thermal analyses of the produced PANI-TiO₂ QDs samples, EDX, BET, and TGA were used. The photocatalytic activity of the PANI-TiO₂ QDs in the photo-degradation of methyl orange dye as an organic hazardous chemical in an aqueous medium was assessed using a 50-watt xenon lamp light source and direct sunlight. PANI-TiO₂ QDs demonstrated high photocatalytic properties, with a 93% efficiency, as opposed to 35% and 60.1%, respectively, for PANI and TiO₂ QDs. When PANI, titanium dioxide quantum dots, and PANI-TiO₂ QDs are present during the recycling processes in the presence of all created samples up to four times, the photo-degradation rate decreases by about 50.2%, 15.4%, and 17.4%, respectively.