One-step formation of TiO2 hollow spheres via a facile microwave-assisted process for photocatalytic activity

Mesoporous TiO2 hollow spheres nanostructures with high surface areas were successfully prepared using a microwave method. The prepared hollow spheres have a size range between 200 and 500 nm. The spheres consisted of numerous smaller TiO2 nanoparticles with an average diameter of 8 nm. The particles had an essentially mesoporous structure with a pore size in the range of 2-50 nm. The results confirmed that the synthesised of anatase TiO2 nanoparticles with specific surface area approximately 172.3 m2/g. The effect of ultra violet and visible light irradiation and catalyst dosage on the TiO2 photocatalytic activity was studied by measuring the degradation rate of methylene blue. The maximum dye degradation performances with low amount catalyst loading (30 mg) were 99 % and 63.4 % using the same duration of ultra violet and visible light irradiation, respectively (120 min).