Preparation and photocatalytic performance of ultrafine tungsten oxide

Sodium tungstate and hydrochloric acid are used as raw materials, carbon nanotubes as template, tungsten acid and carbon nanotube composite are prepared respectively by using one-step and two-step method, and then roasted at 600 ℃ for 2 h under oxygen atmosphere. The average particle size of tungsten acid and carbon nanotubes composite prepared one and two step methods are 10 nm and 100 nm respectively. The average particle size of tungsten oxide powders are 250 nm and 2 μm respectively. The specific surface area of tungsten oxide powders is 36.53 m²/g and 13.99 m²/g respectively. The photocatalytic performance of tungsten oxide is studied by the UV-Vis spectrophotometer using 11W fluorescent light as the light source. The degradation rate of tungsten oxide powders can reach 93.8 % and 79.1 %. The physical absorption and photocatalytic activity of tungsten oxide prepared by one-step method is better than that of two-step method because of its smaller particle diameter and higher specific surface area.