Synthesis and Properties of Complex Crystalline and Glassy Metal Chalcogenides

复杂晶态和玻璃态金属硫属化物的合成与性能

• 批准号: 1410169
• 负责人: Mercouri Kanatzidis
• 金额: $ 49.5万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2017-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1410169&HistoricalAwards=false
• 关键词: Synthesis; Properties; Complex; Crystalline; Glassy

Non-technical SummaryNew materials impact not only the physical sciences but also economic growth. At a grassroots level, the solid state and materials chemistry community recognizes the grand challenge of developing rational materials discovery strategies and identifying materials that are transformative in our understanding of physicochemical properties and in technological progress. With support from the Solid State and Materials Chemistry Program in the Division of Materials Research, this project help address this challenge by developing the chemistry of metal chalcogenides. In this context, the research team is building a rational, science-driven foundation to extract maximum scientific and technological benefit. The primary goals of this projecct are to discover and characterize new types of metal chalcogenide compounds, and to understand their structures, chemical bonding and physical properties. If successful, new materials enabling new applications or enhancing the effectiveness of existing technological applications will emerge. The project employs molten salts as powerful reaction media in which to seek formation of new materials with unusual physical properties. The project contributes significantly to the training and teaching of graduate students in the field of solid state and materials chemistry and helps to create a future workforce that understands the importance of new materials as drivers for new phenomena and technologies. Technical SummaryThe primary goals of this research are to discover and characterize new types of metal chalcogenide compounds, and to understand their structures, chemical bonding and physical properties. The project employs salt flux syntheses to seek new materials with novel structure and compositions. Well-defined building blocks are present in the flux reactions and their formation is guided by tuning the flux composition and temperature, which controls Lewis basicity and redox potential. An important question in this synthesis program is whether, using intermediate temperatures, one can guide the fundamental reaction chemistry occurring in molten salts to suppress the formation of undesirable compounds and favor crystallization of new ones. The project is based on the general theme of structure-composition-property relationships with the following question being central: How does one develop the tools and concepts, both intellectual and experimental, to discover new functional materials. Focusing on the chalcogenide class the project has the following directions: (a) synthesis in polychalcogenide fluxes focusing on early transition and main group metals, mixed metal systems and also on thio and telluro-arsenate and antimonate chemistry; (b) synthesis using mixed chalcogenide fluxes incorporating oxide salts; (c) creation of novel glasses from the crystalline compounds and their phase change behavior and (d) dissolution studies of selected promising chalcogenide phases to assess their potential for processing into more useful forms. The project is expected to enrich the knowledge of unusual and diverse chalcometallate building blocks and role they play in creating new compounds. Experimental characterization tools to be employed include X-ray crystallography optical, infrared and Raman spectroscopy, scanning and transmission electron microscopy, differential thermal analysis and scanning calorimetry, and measurements of electrical conductivity as well as optical second harmonic generation.

非技术总结材料不仅会影响物理科学，而且会影响经济增长。在基层，固态和材料化学界认识到制定理性材料发现策略的巨大挑战，并确定对我们对物理化学特性和技术进步的理解的变革性材料。 在材料研究部固态和材料化学计划的支持下，该项目通过开发金属葡萄糖代化的化学作用来解决这一挑战。在这种情况下，研究团队正在建立一个理性的，以科学为导向的基础，以取得最大的科学和技术利益。该projecct的主要目标是发现和表征新型的金属葡萄干化合物化合物，并了解其结构，化学键合和物理性质。如果成功，将出现新的应用程序或增强现有技术应用的有效性的新材料。该项目采用熔融盐作为强大的反应介质，在其中寻求形成具有异常物理特性的新材料。该项目为固态和材料化学领域的研究生的培训和教学做出了重大贡献，并有助于创建一个未来的劳动力，以了解新材料作为新现象和技术的驱动因素的重要性。技术总结这项研究的主要目标是发现和表征新型的金属葡萄球他植物化合物，并了解其结构，化学键合和物理性能。该项目采用盐通量合成来寻求具有新型结构和组成的新材料。通量反应中存在明确定义的构建块，其形成是通过调整磁通量和温度来指导的，从而控制了刘易斯碱性和氧化还原电位。该合成程序中的一个重要问题是，使用中等温度，是否可以指导熔融盐中发生的基本反应化学以抑制不良化合物的形成并有利于新的化合物的结晶。该项目基于与以下问题相关的结构组成 - 特性关系的一般主题是中心：人们如何开发智力和实验性的工具和概念来发现新的功能材料。 专注于葡萄干化的类别，该项目具有以下方向：（a）聚焦于早期过渡和主要基团金属，混合金属系统以及硫代和泰特罗 - 疗法和抗解化学的聚类元素通量中的合成； （b）使用掺有氧化物盐的混合硫元化的通量合成； （c）从晶体化合物及其相变行为以及（d）对选定有希望的硫族化剂相的溶解研究以评估其加工成更有用的形式的潜力。预计该项目将丰富对不寻常和多样化的构建基础的知识以及它们在创建新化合物中所扮演的角色。要使用的实验表征工具包括X射线晶体学光学，红外和拉曼光谱，扫描和透射电子显微镜，差分热分析和扫描量热法，以及电导率的测量以及光学的第二次谐波产生。