Synthesis, characterization and photocatalytic performance of visible light induced bismuth oxide nanoparticle

Pure and doped Bi2O3 nanoparticles were synthesized by sol gel method. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), UV-Visible Spectroscopy, Scanning Electron Microscopy (SEM), Thermogravimetry/Differential thermal analysis (TGA/DTA), potentiostat/galvanostat (CV), Electron-spin resonance (ESR) and Fourier transform infrared spectroscopy (FTIR). The XRD patterns of the fabricated Bi2O3 nanoparticles exhibited only the characteristic peaks of well crystallized monoclinic α−Bi2O3 and were in pure state. It was found that the crystallite size of doped Bi2O3 nanoparticles decreases with increase in dopant concentration up to certain limit and then decrease. The SEM image depicts that pure and doped Bi2O3 nanoparticles displayed nanorod like morphology; on doping the surface becomes rough. The UV-Vis absorption spectra of synthesized nanoparticles revealed that absorption edge shifts towards the longer wavelength after doping and it is highly beneficial for absorbing more visible light in the solar spectrum. FTIR spectra of doped Bi2O3 nanoparticles showed an additional absorption band. The photocatalytic performance of the as prepared photocatalyst was evaluated by degradation of three different organic dyes as a function of irradiation time.