Dense Extended Hydrocarbon Framework Materials (3D Polymers)

由简单碳氢化合物制成的聚合物固体主要是一维(1D)链，较少出现在像石墨烯这样的2D聚合物中。虽然针对三维烃类聚合物的研究已经导致了低密度的共价有机和金属有机骨架，但高强度和高化学能量密度的致密的三维烃骨架聚合物的合成还没有实现。当这些扩展固体由低Z元素制成时，本质上是硬而轻的，例如钻石和c-BN，并且通常表现出优异的热、机械、化学和电光性能，并构成了一类新的新型材料。在材料研究部固态和材料化学项目的支持下，华盛顿州立大学(WSU)俞宗石教授和他的研究小组将研究第一排和第二排元素固体致密固体混合物的压力诱导转变，旨在开发能够在环境条件下稳定的致密扩展骨架材料(EFM)。这项研究将通过在华盛顿州立大学、大型科学用户设施(APS、LCLS、XFEL)和美国能源部国家实验室(LLNL、LANL、SNL)在尖端实验技术方面的丰富实践经验，为研究生、本科生和博士后研究人员提供非凡的教育和培训机会。该项目的多学科性质也为学生提供了跨多个学科的独特工作经验，通常是在大规模的高知名度研究中，有大量的合作机会。TECHNICAL SUMMARYDense框架结构在高压下随处可见，但通常在极高的压力下形成，释放压力后变得不稳定。因此，只有几个体系在环境条件下被回收，将材料限制在基础科学发现的领域，并倡导一个令人兴奋的新研究领域，以了解并最终控制低Z扩展固体的稳定性、成键、结构和性质。该项目由材料研究部的固态和材料化学计划支持，将使用大压缩、致密的固体混合物和动力学控制过程来控制主要由共价C/H/N/O单键组成的扩展框架材料(EFM)的结构、成键和稳定性。建议的研究工作将集中在三个特定的压力下的固态化学反应：(A)共聚合得到化学计量比的高强度EFM；(B)氧化还原化学到非化学计量填隙填充的多功能EFM；以及(C)界面化学到低维碳和BN中包裹的纳米级EFM。通过科学发现和创新材料开发，拟议的研究将探索各种形式的EFM的结构-性能-功能关系，阐明管理密集固态化学的基本原理，并展示多功能EFM在极端机械、热和化学条件下的革命性能力。拟议的研究战略涉及应用广泛的免费科学方法，从固态材料化学、凝聚态物理、物理化学、材料科学和工程学，从而实现远远超出本提案主题的影响。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL SUMMARYPolymeric solids made of simple hydrocarbons are primarily in one-dimensional (1D) chains and less frequently in 2D polymers like graphene. While research efforts aimed at the development of 3D hydrocarbon polymers have resulted in low-density covalent-organic and metal-organic frameworks, the synthesis of dense 3D hydrocarbon framework polymers with high strength and high chemical energy density has not been achieved. These extended solids, when made of low Z elements, are intrinsically hard yet light, e.g., diamond and c-BN, and often exhibit superior thermal, mechanical, chemical, and electro-optical properties and constitute a new class of novel materials. With this project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, Professor Choong-Shik Yoo and his research group at Washington State University (WSU) will investigate pressure-induced transformations of dense solid mixtures of first- and second-row elemental solids, aimed at development of dense extended framework materials (EFM) amenable to the stabilization at ambient conditions. This research will provide exceptional education and training opportunities for graduate and undergraduate students and postdoctoral researchers through significant hands-on experience in cutting-edge experimental technologies at WSU, large-science user facilities (APS, LCLS, XFEL), and DOE national laboratories (LLNL, LANL, SNL). The multidisciplinary nature of this project also provides students unique experience in working across many academic disciplines, often on large-scale high-profile research, with ample opportunities of enabling collaborations.TECHNICAL SUMMARYDense framework structures are ubiquitous at high pressures, but often formed at formidably high pressures and become unstable upon releasing the pressure. As a result, only a few systems have been recovered at ambient conditions, limiting the materials at the realm of fundamental scientific discovery and advocating an exciting new research area to understand and, ultimately, control the stability, bonding, structure, and properties of low Z extended solids. This project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, will use large compression, dense solid mixtures, and kinetic controlled processes to control the structure, bonding and stability of extended framework materials (EFM) made primarily of covalent C/H/N/O single bonds. The proposed research efforts will be focused on three-specific solid-state chemical reactions under pressures: (A) Copolymerization to stoichiometric high-strength EFM; (B) Redox chemistry to nonstoichiometric interstitial-filled multifunctional EFM; and (C) Interface chemistry to nm-scale EFM encapsulated in low-dimensional carbon and BN. Through scientific discoveries and innovative materials developments, the proposed research will exploit the structure-property-functional relationships of various forms of EFM, elucidate the basic principles governing dense solid-state chemistries, and demonstrate the revolutionary capabilities of multifunctional EFM sustainable to extreme mechanical, thermal and chemical conditions. The proposed research strategy involves application of a broad range of complimentary scientific approaches from solid-state materials chemistry, condensed matter physics, physical chemistry, materials science and engineering, thus achieving the impact well beyond the subject matter of this proposal.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.