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在烷基聚乙烯氧化物(PEO)表面活性剂存在下采用水热或醇热方法合成出了介孔氧化钛,并与无模板体系室温溶胶—凝胶制备的介孔氧化钛进行了比较.这些不同方法制备的氧化钛的结构和特性及形成机理都有明显的不同.在酸性水溶液介质中可合成出双结晶(锐钛矿和板钛矿)结构的、热稳定的、介孔氧化钛,而在醇介质中合成出具有内部大孔结构的介孔氧化钛,其中的介孔是无序分布的呈蠕虫状、由锐钛矿相的氧化钛纳米颗粒聚集形成.无模板溶胶—凝胶制备的介孔氧化钛在焙烧后可得到孔分布11.2nm 的不规则介孔洞.对表面活性剂在介孔结构氧化钛合成中的作用进行了讨论.
Mesoporous titania was synthesized by hydrothermal or alcoholic thermal method in the presence of alkyl polyethylenoxide (PEO) surfactant. The mesoporous titania was prepared by sol-gel method at room temperature without template system. The structure, properties and formation mechanism of titania prepared by these different methods are all obviously different.A double crystalline (anatase and brookite) structure, thermally stable, mesoporous titania can be synthesized in acidic aqueous medium , While mesoporous titania with an internal macroporous structure was synthesized in alcohol medium, in which the mesopores were worm-like disorderedly distributed and formed by the aggregation of anatase-phase titanium oxide nanoparticles. The mesoporous titanium dioxide prepared by sol-gel can obtain irregular mesopores with pore distribution of 11.2 nm after roasting, and the role of surfactants in the synthesis of mesoporous titania was discussed.