Compositionally-Complex Fluorite-based Oxides

非技术描述：该项目探索并扩展了一类新的组成-以萤石为基础的晶体结构中的复杂氧化物，其类似于立方氧化锆宝石，但通常含有五个或更多的金属阳离子。这些新材料可以表现出特殊的性能，例如具有隔热性，同时具有机械刚性和硬度。这项基础研究深入到一个新的研究领域，创造新的陶瓷类。展望了作为新型热障涂层保护飞机、船舶和陆基发电厂使用的燃气涡轮机发动机的潜在应用。此外，创造新的隔热陶瓷可以在其他领域产生影响。例如，这些材料可用于提高聚光太阳能发电厂中的太阳热能产生的效率并降低其成本。该项目培训和指导不同的学生在制造相关的陶瓷科学和技术的航空航天，国防和能源行业的关键领域。 技术详细信息：本研究计画将高熵陶瓷（HEC）的新兴领域拓宽到以萤石基氧化物为模型体系的组成复杂陶瓷（CCC）。这项研究提供了机会，通过无序和有序之间的相互作用，在广阔的组成空间中定制和改善性能。一个核心的科学假设是，CCC中的无序与有序可以用来调整相稳定性，纳米级异质性以及热和机械性能，其中中熵组合物可以胜过它们的高熵对应物。对无序、短程有序和长程有序、氧空位和异质性的基本理解具有广泛的科学意义。研究生和本科生在陶瓷科学和技术的一个至关重要的支柱领域进行指导和培训。西班牙裔高中和大学生通过暑期研究项目受到启发和培训。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL DESCRIPTION: This project explores and expands a new class of compositionally -complex oxides in the fluorite-based crystal structure, which resemble the cubic zirconia gemstone but often contain five or more metal cations. These new materials can exhibit exceptional properties, such as having thermal insulation while being mechanically stiff and hard. This fundamental research delves into a new research field to create new classes of ceramics. Potential applications as new classes of thermal barrier coatings to protect gas turbine engines used in airplanes, ships, and land-based power plants are envisioned. Moreover, creating new thermally insulating ceramics can have impacts in other fields. For example, these materials may be used to increase the efficiency and reduce the cost of solar thermal energy generation in concentrated solar power plants. This project trains and mentors diverse students in a manufacturing-related critical area of ceramic science and technology for the aerospace, defense, and energy industries. TECHNICAL DETAILS: This research project broadens the emerging field of high-entropy ceramics (HECs) to compositionally complex ceramics (CCCs) using the fluorite-based oxides as model systems. This research provides opportunities to tailor and improve properties in a vast compositional space via the interplay between disorder and order. A central scientific hypothesis is that the disorder versus order in CCCs can be utilized to tailor the phase stability, nanoscale heterogeneity, and thermal and mechanical properties, where medium-entropy compositions can outperform their high-entropy counterparts. The fundamental understandings of disorders, short- and long-range orders, oxygen vacancies, and heterogeneity have broad scientific implications. Graduate and undergraduate students are mentored and trained in a critically important mainstay area of ceramic science and technology. Hispanic high school and college students are inspired and trained through summer research projects.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.