CAREER: Hybrid Material Routes to Porous Amorphous Ceramics with Controlled Microstructure

摘要CTS-9624841 本研究的目标是开发以多孔块状凝胶形式或作为具有良好定义的多孔形态和孔化学的薄膜膜的二氧化硅基陶瓷的生成方法。这项工作开发了溶胶-凝胶路线的混合有机/无机材料，可以转化为多孔陶瓷的混合材料的有机成分的全部或部分去除，通过热解或溶剂萃取的合成。 杂化材料将有机成分作为分子良好分散的固体溶质引入二氧化硅-陶瓷网络中，或者作为相分离的介观或宏观域形成并分别用作微孔陶瓷或介孔和大孔陶瓷的前体。 还开发了从杂化材料中选择性地除去非共价键合的有机聚合物并在多孔二氧化硅网络上留下共价键合的有机配体的方法。 这些分子模板方法用于生成具有几个特定目标的明确定义的多孔膜： 可聚合有机配体（例如，通过自由基、离子或消除机制）作为分子模板引入，用于产生表现出高度孔连通性和取向的多孔薄膜; 将金属螯合有机模板与特定的金属或金属离子一起引入到用于形成多孔陶瓷膜的混合薄膜的合成中，所述多孔陶瓷膜表现出高热稳定性、选择性传输特性和/或催化活性; 将表现出特定分子识别性能的有机配体引入到杂化材料中，使得在由它们形成多孔薄膜之后，有机配体优先定位在多孔网络的表面上，因此可以用于开发用于化学传感应用的多孔基质。 教育发展包括修订和改进本科生和研究生化学工程课程的具体方面，包括为化学工程中有风险的本科生建立个性化的教学计划，建立本科生研究计划，特别是为来自代表性不足的族裔群体的学生，以及发展跨学科，工业和联邦（国家实验室）的合作，这将使学生接触到化学，材料科学和微加工领域的各个方面。 该教育计划的一个主要组成部分是实施一项本科研究方案，其主要目标是为代表性不足群体的学生进入研究生院做准备。 这是与新墨西哥州大学已经实施的几个少数民族教育方案合作进行的，以加强少数民族学生，特别是新墨西哥州相对较大的西班牙裔和美洲土著社区成员的研究事业。

ABSTRACT CTS-9624841 The goal of this research is to develop methods of generating silica-based ceramics in the form of porous bulk gels or as thin membrane films that have well-defined porous morphologies and pore chemistries. This work develops sol-gel routes to the synthesis of hybrid organic/inorganic materials that can be converted to porous ceramics by the total or partial removal of the organic component of the hybrid materials through pyrolysis or solvent extraction. Hybrid materials incorporate organic constituents either as molecularly well-dispersed solid solutes in the silica- ceramic network or as phase-segregated mesoscopic or macroscopic domains are formed and used as precursors to microporous ceramics or to mesoporous and macroporous ceramics, respectively. Methods that selectively remove non-covalently bonded organic polymers from hybrid the materials and leave covalently bonded organic ligands on the porous silica networks are also developed. These molecular templating approaches are used to generate well-defined porous films with several specific goals: polymerizable organic ligands (e.g., through free radical, ionic, or elimination mechanisms) are incorporated as molecular, templates for the generation of porous thin films that exhibit high degrees of pore connectivity and orientation; metal-chelating organic templates are incorporated, together with particular metals or metal ions, in the synthesis of hybrid thin films that are used to form porous ceramic membranes that exhibit high thermal stability, selective transport characteristics, and/or catalytic activity; organic ligands exhibiting specific molecular recognition properties are incorporated into hybrid materials such that, after a porous thin film is formed from them, the organic ligands are localized preferentially on the surface of the porous network and hence can be used in the development of porous matrices for chemical sensing applications. Education developments include the revision an d improvement of specific aspects of the undergraduate and graduate chemical engineering curricula, including the establishment of an individualized instruction program for at-risk undergraduate students in chemical engineering the establishment of undergraduate research programs, especially for students from underrepresented ethnic groups, and the development of cross-disciplinary, industrial and federal (National Laboratory) collaborations that will expose students to aspects of the fields of chemistry, materials science, and microfabrication. A major component of this educational plan is the implementation of an undergraduate research program whose main goal is the preparation of students from underrepresented groups for entry into graduate school. This is done in cooperation with several minority educational programs already in place at the University of New Mexico to enhance the access of minority students, especially members of New Mexico's relatively large Hispanic and Native American communities, to research careers.