纳米TiO_2-WO_3的制备及对甲醛的光催化降解

采用溶胶-凝胶法制备TiO2 WO3纳米复合催化剂,对浓度为3 3×10-3mol/L的甲醛溶液进行光催化,考察了不同条件对其光催化降解的影响。结果表明,相同的焙烧温度下,WO3掺杂能抑制粒径的长大;焙烧温度升高,TiO2金红石相质量分数增加,粒径变大;WO3掺杂量为w(WO3)=3%、600℃焙烧时,金红石相质量分数为13 5%,光催化活性最高,甲醛光催化1 5h后降解率达到64%,比纯TiO2光催化活性高出79 4%。

Preparation of TiO2-WO3 Nanopowder and Its Photocatalysis for Formaldehyde Degradation

Nanometer TiO_2-WO_3 composite photocatalyst were prepared by sol-gel method.Photocatalytic degradation experiments for 3.3×10~(-3) mol/L formaldehyde solution were performed to inspect the influence of different preparation conditions on its photocatalytic activity.Doping of tungsten oxide can resist the growth of crystal size at the same calcining temperature.The mass percentage of rutile phase and the crystal size increase with the rise of calcining temperature.When the doping of tungsten oxide is w (WO_3)=3% and calcining temperature is 600 ℃,the mass percentage of rutile phase is 13.5% and the catalytic activity of the composite is the highest.With this photocatalyst,degradation ratio of formaldehyde was 64% after 1.5 h,which is 79.4% higher than the activity of pure nanometer TiO_2.