Investigation of the Photocatalytic Activity of Carbon Doped TiO₂ for Photodegration of Methylene Blue

Abstract

Nanoparticles of pure TiO₂ and carbon doped TiO₂ (at various concentrations 1, 2, 3 and 4 %) were synthesised by Sol gel method using titanium butoxide and glucose as a precursors for Titanium dioxide and carbon respectively. The samples were calcinated at 500 °C. Photocatalytic activity of the samples was tested for photodegradation of methylene blue dye. Morphological and elemental analysis of the samples were carried out using a scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDAX), X-ray diffraction and micro-raman spectroscopy while for optical characterization UV-Vis diffuse reflectance spectra were employed.  Results of all samples indicated crystallite growth in a tetragonal structure with the variation in crystallite size in the range 9 nm to 12.6 nm with increase in the concentration of dopant in TiO₂. Diffused reflectance spectroscopy (DRS) analysis indicated that the band gap of all doped TiO₂ nanoparticles is lesser than that of the pure TiO₂ whereas 4C-TiO₂ showed smallest band gap (2.98 eV). The maximum photocatalytic activity was observed with 4C-TiO₂ among all the samples.