UNS:Nanoporous Platinum -- Atomistic Structure and Catalytic Properties Via Computational Simulations

UNS：纳米多孔铂——通过计算模拟的原子结构和催化性能

• 批准号: 1512759
• 负责人: William Goddard
• 金额: $ 34.42万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-15 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1512759&HistoricalAwards=false
• 关键词: UNS; Nanoporous; Platinum; Atomistic; Structure

Goddard (1512759)The proposal will utilize theoretical tools to obtain insight into structure-function relationships in fuel cell related catalysis by nanoporous metals. The nanoporous materials are not readily accessible by experimental probes due to the small spatial scale involved, their inherent complexity and disorder, and their high ratio of surface- to bulk-atom characteristics. The work will be directed at understanding a poorly understood, yet remarkable, experimental observation that nanoporous platinum obtained by electrochemical dealloying of Ni-Pt particles produces a dramatic optimum activity for the oxygen reduction reaction (ORR) at the Ni7Pt3 composition despite the observed lack of Ni near the surface of the active catalyst. The proposed work will contribute to the development of improved fuel cells for transportation and power applications. It will also provide educational opportunities related to fuel cell catalysis and methods of theoretical simulation of materials properties. The proposal will elucidate the structure-property relationships in the Ni-Pt and other bimetallic particles via first-principles-based theory, reactive molecular dynamics simulations (RMD) and global optimization techniques. The proposal is ambitious in scope, but the PI is a well-established computational scientist with a history of developing refined theoretical techniques and applying them successfully to important problems in catalysis and materials science. The proposal has the potential to be transformative in regards to its ability to gain insight into the properties of nanoscale alloy particles at levels not easily assessed by experimental methods. Novel features of the work include development of a computational method for modeling ORR under electrochemical potential and a plan to extract finite-sized clusters from the complete nanoparticles and subject them to deeper theoretical analysis of the surface properties with respect to adsorption and reaction processes involved in the ORR. Although the specific focus of the proposal is on understanding nanoporous multimetallic particles as they relate to electrocatalysis and use the understanding to design more efficient, durable, and lower-cost fuel cells, the potential impact of the work extends to many areas of nanoparticle application in the general areas of materials science and engineering. These include energy, sustainability, environmental factors, and economic considerations (e.g., non-noble metal materials). The PI is a leader in fuel cell catalysis. As Director of the Materials and Process Simulation Center at Caltech, he has access to a strong team of researchers at all levels to address the complicated interplay between the various components of fuel cell systems - namely catalysts, carbon supports, and polymer membranes. The PI will continue to make software developed in his lab available as open-source packages (i.e. LAMMPS). The PI also has a good track record of incorporating his research into learning oppportunities for minority underrepresented groups and has developed a course related to atomistic modeling of materials.

Goddard (1512759) 该提案将利用理论工具来深入了解纳米多孔金属在燃料电池相关催化中的结构-功能关系。由于涉及的空间尺度小、其固有的复杂性和无序性以及表面原子与体原子特性的高比例，纳米多孔材料不易通过实验探针接近。这项工作将旨在了解一个鲜为人知但引人注目的实验观察结果，即通过 Ni-Pt 颗粒电化学脱合金获得的纳米多孔铂在 Ni7Pt3 成分上产生了显着的氧还原反应 (ORR) 活性，尽管观察到缺乏Ni靠近活性催化剂的表面。 拟议的工作将有助于开发用于运输和电力应用的改进燃料电池。 它还将提供与燃料电池催化和材料性能理论模拟方法相关的教育机会。 该提案将通过基于第一性原理的理论、反应分子动力学模拟（RMD）和全局优化技术来阐明 Ni-Pt 和其他双金属颗粒的结构-性能关系。该提案的范围雄心勃勃，但 PI 是一位成熟的计算科学家，拥有开发精细理论技术并将其成功应用于催化和材料科学中的重要问题的历史。该提案具有变革性的潜力，因为它能够深入了解纳米级合金颗粒的特性，而其水平难以通过实验方法评估。这项工作的新颖之处包括开发一种在电化学势下模拟 ORR 的计算方法，以及从完整纳米颗粒中提取有限尺寸簇的计划，并对它们涉及的吸附和反应过程的表面特性进行更深入的理论分析。 ORR。 尽管该提案的具体重点是了解纳米多孔多金属颗粒，因为它们与电催化有关，并利用这些了解来设计更高效、耐用和成本更低的燃料电池，但这项工作的潜在影响延伸到纳米颗粒应用的许多领域。材料科学与工程的一般领域。其中包括能源、可持续性、环境因素和经济因素（例如非贵金属材料）。 PI 是燃料电池催化领域的领导者。 作为加州理工学院材料和过程模拟中心主任，他拥有强大的各级研究人员团队，以解决燃料电池系统各个组件（即催化剂、碳载体和聚合物膜）之间复杂的相互作用。 PI 将继续以开源包的形式提供其实验室开发的软件（即 LAMMPS）。该 PI 在将其研究成果纳入少数群体的学习机会方面也有着良好的记录，并开发了与材料原子建模相关的课程。