Sol-Gel Synthesized Nanostructured Titania Powders for Photocatalysis

III-10: Sol-Gel Synthesized Nanostructured Titania Powders for Photocatalysis

Lim Suo Hon & Tim White (MSE)

Abstract

Nanostructured TiO2 powders were synthesized by sol-gel techniques at room temperature using titania butoxide Ti(OC4H9)4 as the precursor. The as-prepared amorphous titania was annealed in air to crystallize anatase and rutile. Particle size increased with annealing temperature. Calcinations below 600°C favored the formation of anatase, whereas, rutile only appeared at temperatures higher than 600°C. Above 800°C, rutile began to segregate and the grain size decreased slightly. Grain growth and specific surface area varied inversely such that the BET surface area of titania calcined at 200°C was 248 m2/g and decreased to 0.9329 m2/g after treatment at 800°C. Photocatalytic activity was verified through decolorization of methylene blue.