Mn-N/TiO_2光催化剂的制备及甲基橙的降解

采用溶胶-凝胶法制备了新型Mn-N共掺杂纳米TiO_2复合光催化剂(Mn-N/TiO_2),采用EDX,SEM,UV-Vis,XRD技术对其进行了表征,并将其用于水中甲基橙的可见光催化降解,考察了制备条件对其光催化性能的影响。表征结果显示:Mn-N/TiO_2光催化剂的粒径约为25 nm,且分散性较好;Mn-N共掺杂可增强TiO_2在可见光区域的吸收。实验结果表明:Mn-N/TiO_2的最佳制备条件为硝酸锰、尿素、无水乙醇、冰醋酸与钛酸四丁酯的摩尔比分别为0.000 6,0.24,10,6,焙烧温度400℃;采用最佳条件下制得的Mn-N/TiO_2于可见光下催化处理初始质量浓度为60 mg/L的甲基橙溶液60 min,甲基橙的降解率达92%。

Preparation of Mn-N/TiO2 Photocatalyst and Degradation of Methyl Orange

A new type composite photocatalyst,Mn-N co-doped nano-TiO₂ （Mn-N/TiO₂） was prepared by sol-gel method,and characterized by EDX,SEM,UV-Vis and XRD. The photocatalyst was used for catalytic degradation of methyl orange under visible light,and the effects of preparation conditions on its photocatalytic capability were investigated. The characterized results indicate that：The Mn-N/TiO₂ photocatalysts are particles with 25 nm of size and good dispersity;The Co-doped Mn and N on TiO₂ can increase the visible light absorption. The experimental results show that：The optimum preparation conditions of Mn-N/TiO₂ are the molar ratios of manganese nitrate,urea,anhydrous ethanol and glacial acetic acid to tetrabutyl titanate are 0.000 6,0.24,10,6 respectively,calcination temperature 400 ℃;When the methyl orange solution with 60 mg/L of the initial mass concentration was degraded under visible light for 60 min using the Mn-N/TiO₂ prepared under optimum conditions,the degradation rate reaches 92%.