FRG: Electronic Properties of Polymer-Derived Amorphous Ceramics

非技术描述：聚合物衍生陶瓷是由聚合物前驱体直接热分解合成的一类新型高温陶瓷。与传统陶瓷相比，聚合物衍生陶瓷具有一系列优异的热机械和电子性能，并且具有灵活的加工条件。这些材料适用于许多能源、空间和军事应用。例如用于检测高温、高温压力和辐射环境的微型传感器。了解聚合物衍生陶瓷的结构-电子性能关系可以为进一步设计更好的传感器和开发新的多功能材料提供指导。对学生的培训将有助于为材料及相关行业培养美国下一代科学家和工程师，并保持和加强美国在这一前沿领域的领导地位。技术细节：通过调整聚合前体的化学性质，可以合成具有系统变化结构/成分的聚合物衍生陶瓷。核磁共振、傅里叶变换推断光谱、拉曼光谱、小角度x射线散射、高分辨率透射电子显微镜和扫描隧道显微镜将被用于研究由精心定制的前体合成的聚合物衍生陶瓷的结构。电子顺磁共振和光谱学将用于研究材料的电子和缺陷结构。结构信息将与聚合物衍生陶瓷的电子行为有关，这将通过测量其电导率，霍尔效应和压阻率来表征。拟议的研究将能够更好地调整材料特性以适应不同的技术需求，并为创造新材料提供机会。提出的研究还将为在高温微传感器等新兴技术应用中使用这类新材料提供指导。研究生将接受使用上述所有最先进技术的培训。他们也将有机会在暑假期间在国家实验室或行业进行研究。该项目还将通过让本科生参与专门设计的研究项目来培养他们。

NON-TECHNICAL DESCRIPTION:Polymer-derived ceramics are a new class of high temperature ceramics synthesized by direct thermal decomposition of a polymeric precursor. Compared to conventional ceramics, polymer-derived ceramics possess a set of excellent thermo-mechanical and electronic properties, as well as having flexible processing conditions. These materials are suitable for many energy, space and military applications. Examples include micro-sensors for detecting elevated temperatures, pressures at high temperature, and radiation environments. Understanding the structure-electronic property relationships of polymer-derived ceramics could serve as a guide for further design of better sensors and for the development of new multifunctional materials. Training of students will help to prepare America's next generation of scientists and engineers for materials and related industries, and to maintain and enhance U.S. leadership in this cutting-edge area. TECHNICAL DETAILS:Polymer-derived ceramics with systematically varied structures/compositions will be synthesized by tailoring the chemistry of the polymeric precursors. Nuclear magnetic resonance, Fourier transform inferred spectroscopy, Raman spectroscopy, small angle x-ray scattering, high resolution transmission electron microscopy, and scanning tunneling microscopy will be utilized to study the structures of polymer-derived ceramics synthesized from carefully tailored precursors. Electron paramagnetic resonance and optical spectroscopy will be used to investigate the electronic and defect structures of the materials. The structural information will be related to the electronic behavior of polymer-derived ceramics, which will be characterized by measuring their conductivity, Hall effect and piezoresistivity. The proposed research will enable better tuning of the material properties to different technical needs, and present opportunities for creating new materials. The proposed research will also provide a guideline for using this new class of materials in emerging technical applications, such as, high-temperature micro-sensors. Graduate students will be trained in the use of all of the aforementioned state-of-the-art techniques. They will also have the opportunity during summers to carry out research in national laboratories or industry. This project will also train undergraduate students by involving them into specially-designed research programs.