Characterization of Pore Structure and Coordination of Titanium in TiO(2) and SiO(2)-TiO(2) Sol-Pillared Clays.
Characterization of Pore Structure and Coordination of Titanium in TiO(2) and SiO(2)-TiO(2) Sol-Pillared Clays.
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DOI：
10.1006/jcis.2001.7504
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发表时间：
2001-06
影响因子：
9.9
通讯作者：
Zhe Ding;Hy Y. Zhu;Paul F. Greenfield;Gao Qing Lu
中科院分区：
文献类型：
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作者：
Zhe Ding;Hy Y. Zhu;Paul F. Greenfield;Gao Qing Lu
采用溶胶-凝胶法制备了二氧化钛溶胶-柱状粘土（TiO(2) PILC）和二氧化硅-二氧化钛溶胶-柱状粘土(SiO（2)-TiO(2) PILC）。采用超临界干燥（SCD）和季铵表面活性剂处理来调整所得粘土的孔隙结构。研究发现，SCD方法显著增加了PILCs的外表面积，并且表面活性剂处理可以用于定制孔径，因为在粘土层之间的通道中形成的介孔遵循在MCM-41材料合成中观察到的模板机制。因此获得了高介孔固体。在煅烧的tio2 (2) PILC中，观察到锐钛矿相的超细晶，对有机物具有光催化氧化活性。在SiO(2)-TiO(2) PILCs及其衍生物中，钛高度分散在二氧化硅基体中，未观察到晶相。高度分散的钛位是有机化合物选择性氧化的良好催化中心。版权所有2001学术出版社
Titania sol-pillared clay (TiO(2) PILC) and silica-titania sol-pillared clay (SiO(2)-TiO(2) PILC) were synthesized by the sol-gel method. Supercritical drying (SCD) and treatment with quaternary ammonium surfactants were used to tailor the pore structure of the resulting clay. It was found that SCD approach increased the external surface area of the PILCs dramatically and that treatment with surfactants could be used to tailor pore size because the mesopore formation in the galleries between the clay layers follows the templating mechanism as observed in the synthesis of MCM-41 materials. Highly mesoporous solids were thus obtained. In calcined TiO(2) PILC, ultrafine crystallites in anatase phase, which are active for photocatalytic oxidation of organics, were observed. In SiO(2)-TiO(2) PILCs and their derivatives, titanium was highly dispersed in the matrix of silica and no crystal phase was observed. The highly dispersed titanium sites are good catalytic centers for selective oxidation of organic compounds. Copyright 2001 Academic Press.