Tailoring Hydrogen Storage Performance by Novel Mg-Catalyst Nano-Architectures

优点：氢存储是氢能在车载应用中的瓶颈。在追求金属氢化物作为固态储氢介质的过程中，氢化镁被认为是一个很好的候选者，因为它重量轻，成本低，理论储氢容量高达7.6%。但它的热力学稳定性高，反应动力学慢，限制了它的实际应用。通过调整纳米材料的结构特性，可以设计氢吸附的热力学和动力学，以满足未来的储氢需求。对氢-纳米结构相互作用的基本理解也在很大程度上取决于制造具有所需结构特性的纳米结构的能力。在这个提议中，主要目标是使用一种新的纳米制造技术，掠角沉积（GLAD），来设计和生产具有不同形貌、结构和组成的新型镁催化剂纳米结构。这种制造技术为研究储氢应用的以下重要问题提供了一个载体：(1)不同的纳米结构如何改变储氢行为？(2)纳米级催化剂以不同形式加入到纳米结构储氢材料中，是否会显著提高储氢性能？利用这种纳米制造技术，PI提出了制造具有不同形貌结构的金属氢化物纳米结构，以研究其储氢能力和吸附性能。通过沉积不同尺寸和几何形状的催化剂，可以进一步提高纳米结构的吸氢性能。更广泛的影响：该项目的成功将产生以下好处：(1)它提供了一种制造精心设计的金属氢化物纳米结构或多层纳米结构的通用方法。因此，可以定制成纳米结构的金属氢化物材料并不局限于所提出的材料。(2)利用系统设计的金属氢化物纳米结构和先进的表征技术，可以在基础水平上研究氢如何与定义良好的金属氢化物纳米结构相互作用。(3)找到了制备高效储氢金属氢化物纳米结构的最佳结构和条件。PI将创建的以实验室为基础的纳米技术课程模块将允许本科生和高中生获得纳米制造的实践经验。

0853130ZhaoIntellectual Merits: Hydrogen storage is the bottleneck for using hydrogen energy in on-board vehicle applications. In the pursuit of metal hydrides as solid state hydrogen storage media, magnesium hydride is considered to be a good candidate because of its lightweight, low cost, and high theoretical hydrogen storage capacity of 7.6 wt.%. Unfortunately, its high thermodynamic stability and sluggish reaction kinetics limit its practical applications. By tailoring the structural properties of nanomaterials, the thermodynamics and kinetics of hydrogen adsorption can be designed to satisfy the future hydrogen storage requirements. A fundamental understanding of hydrogen-nanostructure interactions also depends largely on the ability to fabricate nanostructures with the desired structural properties. In this proposal, the main goal is to use a novel nanofabrication technique, glancing angle deposition (GLAD), to design and produce novel Mg-catalyst nano-architectures with different topography, structure, and composition. This fabrication technique provides one with a vehicle to investigate the following important questions for hydrogen storage applications: (1) How would different nanoscale structures change the hydrogen storage behavior? (2) Would nanoscale catalysts, incorporated into nanostructured hydrogen storage materials in different forms, greatly enhance the storage behavior? Using this nanofabrication technique, the PI proposes to fabricate metal hydride nanostructures with different topographic structures to investigate the hydrogen storage ability and sorption performance. The hydrogen sorption performances of the nanostructures will be further improved by depositing different catalysts with different sizes and geometric forms. Broader Impacts: The success of this project will generate the following benefits: (1) It provides a generic methodology to fabricate well-designed metal hydride nanostructures or multilayered nanostructures. Therefore, the metal hydride materials that can be tailored into nanostructures are not limited to the proposed materials. (2) With the systematically designed metal hydride nanostructures and advanced characterization techniques, one can study at a fundamental level how hydrogen interacts with well-defined metal hydride nanostructures. (3) Optimal structures and conditions for fabricating the best metal hydride nanostructures for highly efficient hydrogen storage could be found. The lab-based nanotechnology course module that the PI will create will allow undergraduate and high school students to obtain provide hands-on experience on nanofabrication.