Preparation of Advanced Nanomaterials from Single Source Designer Precursors

从单一来源设计前体制备先进纳米材料

• 批准号: 1411495
• 负责人: Kenton Whitmire
• 金额: $ 39万
• 依托单位: William Marsh Rice 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: 2014-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1411495&HistoricalAwards=false
• 关键词: Preparation; Advanced; Nanomaterials; Single; Source

With this award, the Macromolecular, Supramolecular and Nanochemistry program is funding the research of Kenton H. Whitmire of Rice University to develop new ways to make advanced metallic substances with potentially useful magnetic properties. The work is focusing on materials made from metals such as iron or manganese. When these metals are combined with a substance such as phosphorus, the two can come together in many different forms. Iron combined with phosphorus, for example, can form in at least five ways. All of these resulting substances are different, but they all are semiconductors, some of which display unusual behavior. One of these is called "magnetocaloric". This means their magnetic state varies with temperature. Substances like this could be used to produce an electronic refrigerator, in other words, a solid-state device that does not require the use of refrigerant gases. This work is, thus, having a broad impact: on the production of new and potentially important materials that will find a wide variety of uses in industry, and through the training of the next generation of scientists in advanced techniques for preparing specialized materials.This research is developing new ways to prepare advanced materials that are difficult or impossible to synthesize by conventional means. In order to achieve this goal, new molecular precursors combining one or more transition metals (M) with the group 15 elements (E) are being prepared. The resulting E-M compositions have important magnetic, electronic and/or superconducting properties. This project is geared to overcoming the synthetic challenges of preparing advanced materials of binary, ternary and higher transition metal/main group element compositions. The approach considers single source precursors based on transition metal carbonyl compounds containing one or more transition metals as well as phosphorus and/or arsenic. The molecular precursors are prepared using sophisticated organometallic techniques to achieve the desired E/M compositions. These compounds are characterized by a variety of methods including single crystal X-ray diffraction, multinuclear and variable temperature nuclear magnetic resonance spectroscopy, infrared spectroscopy and mass spectrometry among others. The conversion of these precursors to the desired materials is examined by thermal decomposition methods. The resulting materials, prepared either as nanoparticles or thin films, are analyzed by scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, powder and film X-ray diffraction, energy dispersive X-ray spectroscopy, and other electronic and magnetic measurement techniques.

通过这一奖项，大分子、超分子和纳米化学项目将资助莱斯大学的肯顿·H·惠特迈尔的研究，以开发制造具有潜在有用磁性的先进金属物质的新方法。这项工作的重点是由铁或锰等金属制成的材料。当这些金属与磷等物质结合时，两者可以以许多不同的形式结合在一起。例如，铁与磷的结合至少可以通过五种方式形成。所有这些生成的物质都不同，但它们都是半导体，其中一些表现出不寻常的行为。其中一种被称为“磁热”。这意味着它们的磁态会随着温度的变化而变化。像这样的物质可以用来制造电子冰箱，换句话说，一种不需要使用制冷气体的固态设备。因此，这项工作产生了广泛的影响：对将在工业上有广泛用途的新的和潜在的重要材料的生产，以及通过培训下一代科学家关于制备特殊材料的先进技术。这项研究正在开发新的方法来制备用传统方法难以或不可能合成的先进材料。为了实现这一目标，正在制备将一种或多种过渡金属(M)与15族元素(E)相结合的新的分子前体。得到的E-M组合物具有重要的磁性、电性和/或超导性。该项目旨在克服制备二元、三元和更高过渡金属/主族元素组成的先进材料的合成挑战。该办法考虑了以含有一种或多种过渡金属以及磷和/或砷的过渡金属羰基化合物为基础的单一来源前体。分子前驱体是使用复杂的有机金属技术来制备的，以获得所需的E/M组成。用单晶X-射线衍射法、多核变温核磁共振光谱、红外光谱和质谱学等方法对这些化合物进行了表征。用热分解方法研究了这些前驱体向所需材料的转化。用扫描电子显微镜、透射电子显微镜、X射线光电子能谱、粉末和薄膜X射线衍射、能量色散X射线光谱和其他电磁测量技术对所制备的纳米或薄膜材料进行分析。