CAS: Solution Routes Towards Metastable Functional Chalcogenides

CAS：亚稳态功能硫属化物的解决方案

• 批准号: 2333388
• 负责人: Kirill Kovnir
• 金额: $ 59.8万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-02-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2333388&HistoricalAwards=false
• 关键词: CAS; Solution; Routes; Towards; Metastable

Non-technical SummaryChalcogenide materials, i.e. inorganic materials containing sulfur, selenium or tellurium, are widely used in various applications. Development of novel chalcogenide materials with improved magnetic and thermoelectric characteristics is crucial for the advances in renewable energy harvesting, energy conversion and storage, and information and data storage, among others. In this project, supported by the Solid State and Materials Chemistry program in NSF’s Division of Materials Research, Prof. Kovnir and his research group study approaches to enhancing the solvothermal synthetic capabilities by developing novel synthetic techniques, and the sustainable synthesis of chalcogenide functional materials. The new synthesis methods stabilize metastable functional materials with unprecedented composition, structural fragments, and properties which are not attainable by traditional high-temperature solid state syntheses. Additionally, the researchers prepare unique layered structures of hybrid materials, materials that contain more than one distinct material component. The large interlayer separation makes transition metal-chalcogen layers accessible for soft chemistry modification, stabilizing unprecedented metastable chalcogenides. As part of this award, educational efforts focus on communicating science and chemistry to the public and educating students in Prof. Kovnir’s group to be effective in such communication. Graduate and undergraduate students in Prof. Kovnir’s group are engaged in exciting yet educational chemistry demonstrations at local K-12 schools, and Des Moines Science Center to foster the interest of the general public in STEM.Technical SummaryCurrent solvothermal synthesis is limited to a narrow temperature window dictated by slow kinetics of the reaction near room temperature, or container stability and reactivity at the high-temperature end. In this project, supported by the Solid State and Materials Chemistry program in NSF’s Division of Materials Research, two expansions for the capabilities of current solvothermal synthesis are the development of sustainable activated selenium precursor to perform reaction at near room temperature, and pressurized silica ampoules and molten salts for the high temperature range. A rational combination of the developed synthetic techniques allows for the synthesis of various chalcogenide materials, including chiral hybrid compounds and metastable doped and substituted all-inorganic chalcogenides. Systematic investigations of the reaction mechanisms and structure-property relationships for the produced compounds are carried out to reveal the factors controlling magnetic, thermoelectric, and superconducting properties in these compounds. The new approach produces metastable functional materials with unique properties. Educational efforts are focused on communicating science and chemistry to the public and also educating students to be effective in such communication, in addition to providing a comprehensive materials chemistry education for the students involved in the project.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.

非技术总结材料，即含有硫，硒或柜的无机材料，在各种应用中广泛使用。开发具有改善磁性和热电特性的新型葡萄干化材料对于可再生能源收集，能量转换和存储以及信息和数据存储等的进步至关重要。在该项目中，在NSF材料研究部的固态和材料化学计划的支持下，科夫尼尔教授及其研究小组研究方法是通过开发新型的合成技术以及Chalcogenide功能材料的可持续合成来增强溶剂热合成能力的方法。新的合成方法稳定了具有前所未有的组成，结构片段和特性的亚稳态材料，而传统的高温固态合成无法实现。此外，研究人员准备了混合材料的独特分层结构，这些结构包含多个不同的材料成分。较大的层间分离使过渡金属 - chalcogen层可用于软化学修饰，从而稳定前所未有的亚稳态葡萄球核化合物。作为该奖项的一部分，教育努力着重于向公众传达科学和化学，并教育科夫尼尔教授小组的学生在这种交流中有效。科夫尼尔教授小组的研究生和本科生在当地的K-12学校进行了令人兴奋但教育的化学演示，而得梅因科学中心为了促进公众在STEM中的兴趣。技术摘要溶液的合成仅限于狭窄的温度范围狭窄的温度范围内的较狭窄的窗口范围内的较狭窄的窗口，而室温接近室内温度的较高的室温和众所周知的稳定性，或者概要稳定性。在该项目中，在NSF材料研究部的固态和材料化学计划的支持下，针对当前溶剂热合成能力的两次扩展是可持续活化活化的硒前体的发展，以在近室温下进行反应，并加压硅胶和熔融的高温范围。开发的合成技术的合理组合允许合成各种硫族化物材料，包括手性杂交化合物和亚稳态的掺杂和取代的全无机辣椒剂。对产生化合物的反应机制和结构质体关系进行了系统的投资，以揭示这些化合物中控制磁，热电和超导特性的因素。新方法生产具有独特特性的亚稳态功能材料。教育工作集中在向公众传达科学和化学，并教育学生在为参与该项目的学生提供全面的材料化学教育外，还要有效地进行这种沟通。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查标准来通过评估来通过评估来支持的。