EAGER: Exploring Routes to Nanocomposites Linking Silicate and Carbon-Based Structures

非技术描述：现代技术需要具有特定应用特性的坚固轻质材料。含有硅、碳、氧和氮的纳米结构材料在从锂离子电池电极到火花塞到航空航天工业中的高温材料等应用中都很受关注。到目前为止，它们的合成一直是通过费力和昂贵的途径，涉及有毒的有机硅聚合物前体，并给这类材料命名为聚合物衍生陶瓷（PDC）。本项目探索这些材料和相关材料的替代合成途径。可能会发现具有新结构的材料，并对其性质，稳定性和可能的新应用有所了解。这项研究可能为更经济、更环保的制造方法铺平道路。此外，相关材料可能存在于高压行星内部，因此该项目可能会影响地质学和行星科学以及材料科学。技术细节：航空航天、汽车、核能和其他工业需要在高温下使用坚固、轻便和不反应的陶瓷材料。虽然二氧化硅与碳、碳化硅和/或氮化硅直接反应形成多组分非晶态、玻璃状或结晶材料的进展甚微，但聚合物前驱体途径已经导致了一类非常有趣的新材料——聚合物衍生陶瓷（PDC）。它们最近发现的热力学稳定性表明，它们和/或相关材料应该可以通过其他可能更简单的途径获得。本项目探索这种替代合成，使用各种反应性和纳米相起始材料。目标是产生新的材料，避免昂贵、困难、有毒和危险的有机硅聚合物前体。将探索将有机分子限制在介孔二氧化硅和金属有机框架中的起始材料，以常压热解、激光烧蚀和高压反应为可能的合成途径。此外，相关材料可能存在于高压行星内部，因此该项目可能会影响地质学和行星科学以及材料科学。该项目将培养年轻科学家在合成和表征技术以及合成、结构、物理性质和热力学稳定性方面的相关概念。

NONTECHNICAL DESCRIPTION: Modern technology demands strong lightweight materials with properties tailored to specific applications. Nanostructured materials containing silicon, carbon, oxygen, and nitrogen are of interest in applications ranging from lithium ion battery electrodes to spark plugs to high temperature materials in the aerospace industry. Heretofore their synthesis has been by laborious and expensive pathways involving toxic organosiliicon polymer precursors and giving this class of materials the name polymer-derived ceramics (PDC). This project explores alternate synthesis routes to these and related materials. Materials with new structures may be discovered, and understanding will be gained about their properties, stability and possible new applications. This research may pave the way to more economical and environmentally benign manufacturing methods. Furthermore it is possible that related materials may exist in planetary interiors at high pressure, and this project thus may impact geology and planetary science as well as materials science. TECHNICAL DETAILS: Strong, lightweight and unreactive ceramic materials for use at high temperature are needed for applications in aerospace, automotive, nuclear, and other industries. Though direct reaction of silica with carbon, silicon carbide and/or silicon nitride to form multicomponent amorphous, glassy, or crystalline materials has met with little success, a polymer precursor route, has led to a new class of very interesting materials called polymer-derived ceramics (PDC). Their recently discovered thermodynamic stability suggests that they and/or related materials should be accessible by other, perhaps simpler, pathways. This project explores such alternative syntheses, using various reactive and nanophase starting materials. The goal is to generate new materials avoiding expensive, difficult, toxic, and dangerous organosilicon polymer precursors. Starting materials involving organic molecules confined in mesoporous silica and metal organic frameworks will be explored, with pyrolysis under atmospheric pressure, laser ablation, and high pressure reactions as possible synthetic pathways. Furthermore it is possible that related materials may exist in planetary interiors at high pressure, and this project thus may impact geology and planetary science as well as materials science. This project will train young scientists in synthetic and characterization techniques and in relating concepts in synthesis, structure, physical properties, and thermodynamic stability.