Dunphy Darren R, Garcia Fred L, Kaehr Bryan, Khripin Constantine Y, Collord Andrew D, Baca Helen K, Tate Michael P, Hillhouse Hugh W, Strzalka Joseph W, Jiang Zhang, Wang Jin, Brinker C Jeffrey
University of New Mexico/NSF Center for Micro-Engineered Materials, Department of Chemical and Nuclear Engineering, Albuquerque, NM 87131.
Chem Mater. 2011 Apr 26;23(8):2107-2112. doi: 10.1021/cm1033723.
The fabrication of nanostructured films possessing tricontinuous minimal surface mesophases with well-defined framework and pore connectivity remains a difficult task. As a new route to these structures, we introduce glycerol monooleate (GMO) as a template for evaporation-induced self-assembly. As deposited, a nanostructured double gyroid phase is formed, as indicated by analysis of grazing-incidence small-angle x-ray scattering data. Removal of GMO by UV/O(3) treatment or acid extraction induces a phase change to a nanoporous body-centered structure which we tentatively identify as based on the IW-P surface. To improve film quality, we add a co-surfactant to the GMO in a mass ratio of 1:10; when this co-surfactant is cetyltrimethylammonium bromide, we find an unusually large pore size (8-12 nm) in acid extracted films, while UV/O(3) treated films yield pores of only ca. 4 nm. Using this pore size dependence on film processing procedure, we create a simple method for patterning pore size in nanoporous films, demonstrating spatially-defined size-selective molecular adsorption.
制备具有三连续最小表面中间相、明确骨架和孔隙连通性的纳米结构薄膜仍然是一项艰巨的任务。作为通往这些结构的新途径，我们引入甘油单油酸酯（GMO）作为蒸发诱导自组装的模板。沉积时，形成了纳米结构的双螺旋相，掠入射小角x射线散射数据分析表明了这一点。通过UV/O(3)处理或酸萃取去除GMO会导致相变为纳米多孔体心结构，我们初步确定其基于IW-P表面。为了提高薄膜质量，我们以1:10的质量比向GMO中添加一种共表面活性剂；当这种共表面活性剂是十六烷基三甲基溴化铵时，我们发现在酸萃取薄膜中孔径异常大（8-12纳米），而UV/O(3)处理的薄膜产生的孔径仅约为4纳米。利用这种孔径对薄膜加工过程的依赖性，我们创建了一种在纳米多孔薄膜中图案化孔径的简单方法，证明了空间定义的尺寸选择性分子吸附。
