Enhanced photocatalytic performance of polyaniline nanoparticles for efficient dye degradation under simulated sunlight

This study investigates the effectiveness of polyaniline oxide (PANI) nanoparticles as photocatalysts for the degradation of organic dyes under visible light irradiation. Known for their stability and adjustable conductivity, PANI nanoparticles were synthesized <i>via</i> a hydrothermal method using P123 surfactants, followed by calcination. The morphology, structural phase, and optical properties of the synthesized PANI materials were analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). Results indicated that the synthesized PANI nanoparticles agglomerated into spherical particles with an average size of 70-80 nm. The photocatalytic properties of PANI materials were evaluated by the decolorization of rhodamine B (RhB) and methylene blue (MB) under simulated sunlight irradiation. The PANI photocatalyst was found to be highly effective in removing MB dye, achieving a removal efficiency of approximately 97.09% with a rate constant of 2.08 × 10^-2 min^-1. In comparison, the removal efficiency for RhB was about 58.01%. Additionally, the mechanism behind the photocatalytic degradation of MB dye by PANI was investigated and discussed. The study highlights the photostability and reproducibility of PANI nanoparticles through recycling experiments, contributing to the development of sustainable photocatalytic materials for efficient water treatment.