溶胶-凝胶-微波法制备银掺杂TiO_2光催化剂及其光催化性能

用硝酸银和钛酸正丁酯为原料,采用溶胶-凝胶-微波辐射干燥法合成银掺杂TiO_2光催化剂TiO_2-Ag。为了提高催化剂的光催化活性和降解有机污染物的速率,用微波辅助Ti O2-Ag光催化剂降解有机污染物。通过扫描电子显微镜、红外光谱法、紫外可见光谱法和荧光光谱法对TiO_2-Ag催化剂进行测试和表征。以甲基橙为有机污染物,分别在太阳光照射和微波、紫外、紫外-微波条件下降解甲基橙以考察催化剂的光催化活性。结果表明,TiO_2-Ag光催化剂最佳制备条件为:银掺杂量n(Ag+)∶n(Ti~(4+))=0.003,离子液体用量3.0 m L,微波干燥功率210 W,微波干燥时间20 min,焙烧温度650℃,焙烧时间3 h,此条件下制备的TiO_2-Ag光催化剂在太阳光照射4 h下,紫外光照、微波辐射和紫外光照-微波辐射分别辐射55 min后,甲基橙降解率分别为98.70%、98.79%和99.05%。

Preparation of Ag-doped TiO2 photocatalyst by sol-gel and microwave radiation method and its photocatalytic performance

Using silver nitrate and tetrabutyl titanate as raw materials,Ag-doped TiO₂ photocatalysts were prepared by sol-gel and microwave radiation drying method.The microwave assisted Ag-doped TiO₂ photocatalyst was applied in the degradation of organic pollutants in order to improve photocatalytic performance of the catalysts and accelerate the degradation rate of organic pollutants.Ag-doped TiO₂ photocatalysts were characterized by scanning electron microscopy,infrared spectroscopy,UV-Vis spectroscopy and fluorescence spectroscopy.The photocatalytic activity of the as-prepared photocatalysts for degradation of methyl orange was investigated under the irradiation of sun light,microwave irradiation,ultraviolet and ultraviolet microwave.The results showed that the optimal preparation condition was as follows:n(Ag⁺)∶n(Ti⁴⁺)=0.003,ionic liquid amount 3.0 mL,microwave drying power 210 W,microwave drying time 20 min,calcination temperature 650 ℃ and calcination time 3 h.TiO2-Ag catalyst prepared under the optimal condition possessed better photocatalytic performance.The degradation rate of methyl orange were 98.70%, 98.79% and 99.05%,respectively after the irradiation of sun light for 4 h,and then UV,MW and UV-MW respectively for 55 min.