NIRT: Tailored Fluorinated Surfactant Templates for the Design of Ordered Nanoporous Ceramics

这个跨学科的研究团队将致力于使用一种新型的结构导向剂--氟化表面活性剂来设计有序的纳米多孔金属氧化物和有机-无机杂化材料。含氟表面活性剂比碳氢表面活性剂更容易组装，形成低界面曲率的稳定相，同时具有疏水性和疏水性，为有序多孔材料的模板化和回收提供了一种新的平台。从传统的基于碳氢表面活性剂的技术出发，我们将首先系统地探索氟化表面活性剂结构对模板法制备多孔二氧化硅的影响。这个项目的目标是设计具有更严格可控孔结构的表面活性剂模板纳米结构，该项目将整合分子模拟、含氟表面活性剂合成、物相表征和材料合成技术。我们还将利用氟化物在低表面张力流体(如超临界二氧化碳)中的选择性溶解，以提高从纳米孔陶瓷中回收模板的能力。由于氟化表面活性剂可以在温和的条件下被提取，它们的使用有望改进合成具有纳米结构孔的有机-无机杂化材料的方法。分子前驱体的共同组装使纳米结构陶瓷的合成接近生物材料的功能和效率。用选定的分子片段对孔壁进行功能化处理，进一步增强了这些无机材料用于催化剂、分离材料、传感器和微型诊断设备的潜力。该项目的研究和教育活动的协同方法将通过分子模板化和有机功能化来推进基于氟表面活性剂的新纳米体系的设计。该奖项通过NSF的两个主管部门共同支持：(I)数学和物理科学部(陶瓷和固态化学计划的材料研究部)和(Ii)工程部(纳米制造计划的设计、制造和工业创新部)。

This interdisciplinary research team will address using a new class of structure directing agents, fluorinated surfactants, for the design of ordered nanoporous metal oxides and organic-inorganic hybrid materials. Fluorinated surfactants provide a novel platform for both templating of and recovery from ordered porous materials because they assemble more readily than hydrocarbon surfactants, form stable phases of low interfacial curvature, and are both hydrophobic and lipophobic. Departing from a traditional technique based on hydrocarbon surfactants we will first systematically explore the effects of fluorinated surfactant structure on the templating of porous silica. With a goal of designing surfactant-templated nanostructures with more tightly controlled pore architecture, this project will integrate molecular simulations, fluorinated surfactant synthesis, phase characterization, and materials synthesis techniques. We also will exploit the selective solubility of fluorinated species in low surface tension fluids (such as supercritical carbon dioxide) to enhance template recovery from nanoporous ceramics. Because fluorinated surfactants can be extracted under mild conditions, their use is expected to improve methods of synthesizing organic-inorganic hybrid materials with nanostructured pores.The co-assembly of molecular precursors allows the synthesis of nanostructured ceramics that approach the functionality and efficiency of biological materials. "Functionalizing" the pore walls with selected molecular fragments further enhances the potential of these inorganic materials for catalysts, separation materials, sensors and miniaturized diagnostic devices. The synergistic approach to the research and educational activities of this project will advance the fluorosurfactant-based design of new nanosystems by molecular templating and organic functionalization.This proposal was submitted in response to the solicitation "Nanoscale Science and Engineering" (NSF 01-157). The award is jointly supported through two directorates at NSF: (i) Mathematical and Physical Sciences (Division of Materials Research in the Ceramics and Solid-State Chemistry programs) and (ii) Engineering (Division of Design, Manufacture and Industrial Innovation in the Nanomanufacturing program).