Structural and optical investigations of starch-assisted Mn-Doped WO <sub>3</sub> nanoparticles for photocatalytic degradation of dyes
Manjula Tiwari, G. C. Joshi, Amit Joshi
Abstract
In this work, pure and Mn-doped WO3 nanoparticles (NPs) were prepared by a starch-assisted precipitation method. X-Ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Raman analysis, Fourier Transform Infrared Spectra (FTIR), Ultraviolet-Visible (UV-Vis) spectroscopy, X-ray photoelectron spectroscopy (XPS) and Photoluminescence (PL) spectroscopy were techniques to characterise the pure and Mn-doped WO3 NPs. Under sunlight irradiation, the Mn-doped WO3 NPs had been employed to degrade the organic contaminants Rhodamine B (RhB) and Crystal Violet (CV). The 10 wt% Mn–WO3 catalyst showed improved photocatalytic activity towards the degradation of CV and RhB when compared to pure WO3 and 5 wt% Mn–WO3 NPs. The Mn ions on the surface of the WO3 NPs, which hinder the recombination of photogenerated electron–hole pairs, were primarily responsible for the improvement of photocatalytic activity. A description of the photocatalytic mechanism of Mn-doped WO3 was also provided. This novel Mn-doped WO3 NPs worked well as a tool catalyst to reduce organic impurities.