煅烧条件对TiO_2/硅藻土复合材料光催化性能研究

Influence of calcination condition on photocatalytic property of nano-TiO_2/diatomite composite material

利用硅藻土结构特性和纳米二氧化钛(TiO_2)优越光催化活性,以提纯硅藻土为载体,钛酸四丁酯为前驱体,采用溶胶-凝胶法制得纳米TiO_2/硅藻土光催化复合材料。通过XRD、EDS、SEM、FT-IR对复合材料进行晶型结构和形貌表征分析,考察煅烧条件对复合材料光催化性能影响。实验结果表明:TiO_2/硅藻土复合材料最佳煅烧温度为650℃、煅烧时间3h,此时TiO_2晶型以混晶形式存在,晶粒尺寸为39.9nm;在300W高压汞灯光照3h对罗丹明B溶液降解率达到100%,经过5次重复利用后对罗丹明B降解率仍达到70.53%以上。

In order to make use of the structure characteristic of diatomite and the photocatalytic activity of nano TiO2,using purified diatomite as carrier and etrabutyl titaanate as precursor,the nano-TiO2/diatomite composite material was prepared by sol-gel method.The crystalline structure and morphology of composite were characterized by XRD,EDS,SEM and FT-IR,the effect of the calcination conditions on the photocatalytic properties of composite were investigated.The results showed that the photocatalytic property of composite was the best when the calcination temperature was 650℃ and the calcination time was 3 h.At this time,the crystal of TiO2 had mixed crystal form,the crystal size was 39.9 nm.The degradation rate of rhodamine B was 100% after irradiation by 300 W high pressure mercury lamp for 3 h,and the degradation rate of Rh B was over 70.53% after 5 times recycling.