CAREER: Enhancing Atomic Mobility and Desorption Kinetics in Metal Hydrides

职业：增强金属氢化物中的原子迁移率和解吸动力学

• 批准号: 1231153
• 负责人: Tabbetha Dobbins
• 金额: $ 26.92万
• 依托单位: Rowan University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1231153&HistoricalAwards=false
• 关键词: CAREER; Enhancing; Atomic; Mobility; Desorption

NON-TECHNICAL DESCRIPTION: The project is designed to aid in the development of the hydrogen economy and to stimulate public discourse on the topic of on-board vehicular hydrogen storage for fuel cells and electric motors by implementing research and educational outreach activities. The research projects will study important unanswered questions which limit the implementation of hydrogen as a practical and viable fuel source. Specifically, the role of catalysts in metal hydrides will be studied using state-of-the-art instrumentation located at synchrotron x-ray and neutron facilities within the U.S. and abroad. Investigations will surround the questions: ?How do catalysts facilitate the removal and uptake of H2 gas in metal hydride powders (e.g. NaAlH4 or LiBH4)?? and ?Do the same catalysts act to enhance or decrease long range atomic movement in the hydride powders?? Other projects instituted by this funding will include a high school design challenge project to be instituted annually with a team of students. The high school program will be called Project ENERGY (Exploring New Energy-alternatives Relevant to Generation Y) (see projectEnerG.com for updates).TECHNICAL DETAILS: The objective of this proposal is to understand the influence of catalytic additives in enhancing atomic mobility and desorption rates in metal hydrides (specifically, NaAlH4 and LiBH4). The adaptation of sintering models to a new class of materials will be investigated, while incorporating x-ray and neutron scattering studies to understand local lattice changes in these hydrides during desorption. Prior experimental investigations to understand the role of catalysts have been limited to single-experiments such as x-ray absorption spectroscopy, nuclear magnetic resonance, or direct imaging to understand the local structure around the catalysts. Alternatively, the proposed project approaches this problem by applying an entire paradigm. In order to build concepts in understanding the role of the transition metals in hydrides, ideas are taken from a well-developed field of study (i.e., ceramic sintering and densification) wherein it is understood how dopants effect diffusion and mass transport. Studies will investigate the effect of transition metal catalytic additives on atomic mobility at various stages of the H2 desorption process. Synchrotron x-ray scattering data aid in understanding the relative roles of mass transport and H2 desorption on microstructure remediation. Concentration and type of point defects formed as a result of catalytic additions will be determined using positron annihilation studies. As well, in situ synchrotron x-ray diffraction, neutron diffuse scattering studies with atomic pair distribution function analysis, and x-ray absorption spectroscopy will enable examination of local lattice strains, lattice amorphization and catalyst local structure upon hydrogen desorption and uptake. The PI has a history of mentoring student researchers at synchrotron x-ray studies ? many from underrepresented groups, through her joint faculty position between Grambling State University, a historically Black university, and Louisiana Tech University. This program will support both undergraduate and graduate students. Educational activities include new courses on synchrotron x-ray studies and alternative energy, and a high school outreach program.

非技术描述：该项目旨在通过开展研究和教育外联活动，协助发展氢经济，并鼓励公众讨论燃料电池和电动机车载氢储存问题。 这些研究项目将研究限制氢作为一种实用和可行的燃料来源的重要未回答的问题。 具体来说，将使用位于美国和国外同步加速器X射线和中子设施的最先进仪器研究催化剂在金属氧化物中的作用。调查将围绕以下问题展开：催化剂如何促进金属氢化物粉末（例如NaAlH 4或LiBH 4）中H2气体的去除和吸收？然后呢？相同的催化剂是否会增强或减少氢化物粉末中的长程原子运动？由这笔资金设立的其他项目将包括一个高中设计挑战项目，每年与一个学生团队一起设立。 该高中项目将被称为能源项目（探索与Y代相关的新能源替代品）（见projectEnerG.com更新）。技术支持：该提案的目的是了解催化添加剂在提高金属硫化物（特别是NaAlH 4和LiBH 4）中的原子迁移率和解吸速率方面的影响。 将研究烧结模型对一类新材料的适应性，同时结合X射线和中子散射研究，以了解解吸过程中这些晶体的局部晶格变化。 以前的实验研究，以了解催化剂的作用已被限制到单一的实验，如X射线吸收光谱，核磁共振，或直接成像，以了解催化剂周围的局部结构。 或者，拟议的项目通过应用整个范例来解决这个问题。 为了建立理解过渡金属在金属氧化物中的作用的概念，从一个成熟的研究领域（即，陶瓷烧结和致密化），其中理解掺杂剂如何影响扩散和质量传输。 研究将调查过渡金属催化添加剂在H2解吸过程的各个阶段对原子迁移率的影响。 同步辐射X-射线散射数据有助于理解微观结构修复的质量传输和H2解吸的相对作用。浓度和类型的点缺陷形成的催化添加的结果将被确定使用正电子湮没研究。同时，原位同步加速器X射线衍射，中子漫散射研究与原子对分布函数分析，和X射线吸收光谱将使检查局部晶格应变，晶格非晶化和催化剂的局部结构后，氢解吸和吸收。 PI有指导同步加速器X射线研究学生研究人员的历史吗？许多来自代表性不足的群体，通过她在格兰布林州立大学，一所历史上的黑人大学和路易斯安那理工大学之间的联合教职。 该计划将支持本科生和研究生。 教育活动包括关于同步加速器x射线研究和替代能源的新课程，以及一个高中外展计划。