Short time deposition of TiO2 nanoparticles on SiC as photocatalysts for the degradation of organic dyes

Abstract

The deposition of TiO2 nanoparticles on SiC was carried out by mechanical milling under different conditions. SiC–TiO2 samples were used as photocatalysts for the degradation of organic dyes such as methylene blue and rhodamine B. A short time deposition of TiO2 nanoparticles was observed during mechanical milling (2 min at 200 rpm) to cover the SiC particles. The presence of SiC and TiO2 (anatase and rutile) was confirmed by means of X-ray diffraction after thermal treatment at 450 °C. The deposition of TiO2 on SiC was corroborated by scanning electron microscopy analysis; the thickness of the thin layer of TiO2 deposited on SiC increases as the proportion of TiO2 increases. The energy band gap values obtained for these compounds were around 3.0 eV. SiC–TiO2 photocatalysts prepared by mechanical milling exhibited better activity under UV-light irradiation for the degradation of methylene blue and rhodamine B than commercial TiO2 powder (titania P25).