Development of polyaniline coated titania-hematite composite with enhanced photocatalytic activity under sun-like irradiation

Herein, a novel PANI@Fe2O3@TiO2 (PANI@TF) composite containing different amounts of polyaniline was synthesized by in situ polymerization of aniline monomer in the presence of TF. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), BET surface area, Diffuse reflectance spectroscopy (DRS), X-ray photoelectron (XPS), and scanning electron microscopy (SEM-EDS) were used to study the phase structure, morphology, and optical properties of the synthesized PANI@TF composites. Moreover, for the first time, the photocatalytic property of the as-synthesized PANI@TF composites has been evaluated via the decolorization of MB under sun-like illumination. The findings confirmed that all the PANI@TF ternary composites with different PANI content showed enhanced visible-light photocatalytic activity for methylene blue (MB) dye degradation compared to pure Fe2O3@TiO2. The highest degradation efficiency for MB via 1% PANI@TF ternary catalyst reached 96% after 2 h under sun-like illumination, which was 4.3 higher than TF. Finally, a plausible photocatalytic mechanism for the improved photocatalytic activity was proposed to guide further improvement of its photocatalytic performance.