孔径可调的介孔SiO2自支持薄膜的溶剂挥发诱导自组装合成与表征

以十六烷基三甲基溴化铵(CTAB)为模板剂, 正硅酸乙酯为硅源, 在弱酸性条件下利用溶剂挥发诱导自组装(EISA)合成出具有介孔结构的二氧化硅薄膜. 通过控制EISA过程中溶剂挥发的环境, 可在1.4~3.1 nm的范围内调节介孔结构的孔径. 实验表明, 较快的溶剂挥发速率有助于较大孔径的介孔结构生成. 用该方法合成的介孔薄膜具有蠕虫状孔道结构和良好的孔径均一性. 在外观上, 该薄膜具有均匀、透明和无缺陷等特点, 可以自支撑, 并且具有一定的韧性.

Synthesis and Characteristic of Pore Size-tailored Self-supporting Mesoporous Film via Solvent Evaporation Induced Self-assembly

Mesoporous silica films with pore diameters of 1.7—3.1 nm were synthesized through evaporation induced self-assembly using CTAB as surfactant and TEOS as Si source in weak acid media. The films were flexible, self-supporting and centimeter-sized with wormhole-like channel systems. By controlling the solvent remove process, the pore size of films could be tailored without negative influence on the pore size uniformity. A fast volatilization speed would lead to a large pore size, while a slow volatilization speed would result in a small pore size.