氮掺杂TiO_2可见光光催化剂的制备及性能

以尿素和钛酸丁酯为原料,通过溶胶-凝胶法低温下制备了高可见光催化活性的氮掺杂TiO2（NDT）光催化剂,采用XRD、TEM、BET和UV-Vis DRS等测试手段对其进行了表征,并在自制光催化反应器中降解甲基橙评价了样品的光催化活性。结果表明,当氮与钛的摩尔比为0.5∶1时,350℃焙烧的样品（NDT350）具有最佳的可见光光谱吸收和光催化活性,该催化剂为锐钛矿晶相,平均粒径为21 nm,比表面积为89.13 m2/g。可见光辐照下,NDT350降解甲基橙的表观反应速率常数为1.381×10-2min-1,是商业P25催化剂的16.85倍。NDT350优良的可见光催化活性与其大的比表面积和强烈的可见光光谱吸收有关。

Preparation and performance of nitrogen-doped photocatalyst with visible light response

N-doped TiO2（NDT） was prepared by a sol-gel method at low temperature using urea and tetrabutyl titanate as precursors.The prepared samples were characterized by XRD,TEM,BET and UV-Vis DRS.Its photocatalytic activity was examined by the degradation of methyl orange（MO） in a homemade photocatalytic reactor.When the mole ratio of nitrogen to titanium is 0.5∶ 1,N-doped TiO2 calcined at 350℃（NDT350） exhibits the strongest visible light absorption and the highest photocatalytic degradation towards MO under visible light irradiation.NDT350 is in anatase phase with its average particle size and specific surface area reaches 21 nm and 89.13 m2/g,respectively.Under visible light irradiation,the apparent rate constant of the NDT350 catalyst reaches 1.381×10-2 min-1 which is 16.85 times of that of Degussa P25.The high visible photocatalytic activity of NDT350 may be attributed to its large specific surface area and strong visible light absorption.