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.

戈达德（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。纳米多孔材料是不容易通过实验探针，由于所涉及的小空间尺度，其固有的复杂性和无序性，以及它们的表面原子与体原子特性的高比率。这项工作将是针对理解一个知之甚少，但显着的，实验观察到的纳米多孔铂通过电化学脱合金的Ni-Pt颗粒产生一个戏剧性的最佳活性的氧还原反应（ORR）在Ni 7 Pt 3组合物，尽管观察到的活性催化剂的表面附近缺乏镍。 拟议的工作将有助于改进燃料电池的运输和电力应用的发展。 它还将提供与燃料电池催化和材料特性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）和全局优化技术阐明Ni-Pt和其他纳米粒子的结构-性能关系。该提案在范围上雄心勃勃，但PI是一位成熟的计算科学家，具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。该提案有可能在其深入了解纳米级合金颗粒性能的能力方面具有变革性，这些性能不易通过实验方法进行评估。这项工作的新特点包括开发一种用于在电化学电势下建模ORR的计算方法，以及一项从完整的纳米颗粒中提取有限大小的簇的计划，并对ORR中涉及的吸附和反应过程进行更深入的表面性质理论分析。 虽然该提案的具体重点是理解纳米多孔多金属颗粒，因为它们与电催化有关，并利用这种理解来设计更高效，耐用和低成本的燃料电池，但这项工作的潜在影响扩展到许多领域纳米颗粒应用在材料科学和工程的一般领域。这些因素包括能源、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工艺模拟中心的主任，他可以接触到各级强大的研究人员团队，以解决燃料电池系统各个组件之间的复杂相互作用-即催化剂，碳载体和聚合物膜。PI将继续将其实验室开发的软件作为开源软件包（即LAMMPS）提供。PI也有一个良好的记录，将他的研究纳入少数代表性不足的群体的学习机会，并开发了一门与材料的原子建模相关的课程。