PMMA为模板合成多孔TiO_2微米球及紫外光催化性能

PMMA-Templated Synthesis of Porous TiO_2 Micro-Spheres and Application in Photocatalysis

以聚甲基丙烯酸甲酯(PMMA)球为模板,用溶剂热法制备了具有多孔结构的TiO2微米球.用扫描电镜、X射线衍射、N2-吸脱附、热重分析对样品进行表征,并通过对亚甲基蓝的紫外光催化降解评价样品的光催化性能.结果表明,样品为单分散的锐钛矿晶型TiO2球形颗粒,其直径在4μm左右,溶解法去除PMMA模板后得到以微孔为主的多孔TiO2微米球,若再对其进行水热处理,则样品中大部分微孔转变为中孔,得到以中孔为主的多孔TiO2微米球.水热处理后,样品结晶度好,热稳定性高,比表面积为138 m2·g-1,对亚甲基蓝(MB)的光催化降解效果较好,光照40 min后降解率达到97.4%.

Micrometer-scaled TiO2 spheres were successfully synthesized with poly（methyl methylacrylate）（PMMA） template by solvothermal treatment using titanium n-butoxide and acetic acid as reactants.The obtained TiO2 spheric materials were characterized by scanning electron microscope（SEM）,X-ray diffrac-tion（XRD）,N2 adsorption-desorption and thermogravimetric analysis（TGA）.The ultraviolet photocatalytic activity of the obtained materials was evaluated by decomposing methyene blue.The SEM result showed that the obtained samples were uniform anatase TiO2 spheres with diameter about 4 μm.PMMA in samples were removed by calcination or dissolution methods.The BET specific surface areas differed with the treat-ment methods.The sample possessed specific surface areas of 138 m2？g-1 and porous structure when the PMMA in the sample was dissolved by ethyl acetate before hydrothermal.The TiO2 spheric material exhib-ited a good photocatalytic activity,the degradation rate was about 97.4% after 40 min irradiation by UV light.