Specific Surface Area and Three-Dimensional Nanostructure Measurements of Porous Titania Photocatalysts by Electron Tomography and Their Relation to Photocatalytic Activity
Specific Surface Area and Three-Dimensional Nanostructure Measurements of Porous Titania Photocatalysts by Electron Tomography and Their Relation to Photocatalytic Activity
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DOI：
10.1017/s1431927610094419
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发表时间：
2011-03
影响因子：
2.8
通讯作者：
Kenta Yoshida;M. Makihara;N. Tanaka;S. Aoyagi;E. Nishibori;M. Sakata;E. Boyes;P. Gai
中科院分区：
文献类型：
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作者：
Kenta Yoshida;M. Makihara;N. Tanaka;S. Aoyagi;E. Nishibori;M. Sakata;E. Boyes;P. Gai
摘要利用电子层析成像技术，在真实的空间对各种多孔二氧化钛光催化剂进行了三维分析。从3D数据成功地重建了细孔和孔内银（Ag）颗粒（直径2 nm）的三维（3D）分布。应用电子断层扫描测量多孔结构的比表面积，包括开放和封闭孔隙率。计算出的比表面积为22.8 m2/g的常规溶胶-凝胶二氧化钛样品和366 m2/g的高度多孔二氧化钛样品制备使用普朗尼克P-123自组装过程进行了比较与那些通过一般BET方法测量。实空间表面测量表明，高度多孔的二氧化钛本方法使用嵌段共聚物具有更大数量的有效反应位点的降解亚甲基蓝。电子断层扫描显示出巨大的潜力，大大有助于纳米结构的分析和设计，这样的催化剂材料的催化剂。
Abstract Various porous titania photocatalysts are analyzed three-dimensionally in real space by electron tomography. Shapes and three-dimensional (3D) distributions of fine pores and silver (Ag) particles (2 nm in diameter) within the pores are successfully reconstructed from the 3D data. Electron tomography is applied for measuring the specific surface area of the porous structures including open and closed porosity. Calculated specific surface areas of 22.8 m2/g for a conventional sol-gel TiO2 sample and 366 m2/g for a highly porous TiO2 sample prepared using the Pluronic P-123 self-assembly process are compared with those measured by the general BET method. The real-space surface measurement indicates that the highly porous TiO2 produced by the present method using block copolymers has a greater number of effective reaction sites for the degradation of methylene blue. Electron tomography shows a great potential to contribute considerably to the nanostructural analysis and design of such catalyst materials for photocatalysis.