Mechanisms and Rates for Improved Fuel Cell Cathode Catalysts and Supports from First Principles Based Methods

改进燃料电池阴极催化剂的机制和速率以及基于第一原理的方法的支持

• 批准号: 1067848
• 负责人: William Goddard
• 金额: $ 33万
• 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: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1067848&HistoricalAwards=false
• 关键词: Mechanisms; Rates; Improved; Fuel; Cell; Mechanisms; Rates; Improved; Fuel; Cell

If progress is to be made at ultimately overcoming the technical and cost limitations of PEM fuel cells, a significant investment in the fundamental science of the reactions taking place must be made. The objective for this proposal is to determine the detailed atomistic mechanism including free energy barriers for the oxygen reduction reaction at PEM fuel cell cathodes. The focus is on how the mechanism and rates depend on alloy composition, distribution between surface and bulk regions, and solvent. The computational results would be tested by predicting how binary and ternary catalysts would be expected to improve selectivity, rates, and lifetime. In addition, the PIs, William A. Goddard III Boris Merinov, both of the Materials and Process Simulation Center at California Institute of Technology, propose to determine mechanisms of catalyst degradation and how they depend on alloy composition. The result is to be a computational model sufficiently accurate to be useful in guiding both experiments and engineering applications. There has previously been no practical means to couple such a wide range of reactive phenomena based solely on first principles. This novel approach would predict data for engineering models from first principles, allowing new systems to be designed computationally and then tested against experiment. To enable this model testing, collaborations have been arranged with Argonne National Labs and with Ford Scientific Labs to carry out experiments on those alloys predicted to be most promising. This model should aid the development of accurate engineering models informed from the theory and simulations but adjusted to incorporate results from experiments. This approach will be essential to develop the improved materials and processes needed to enable new alloys to meet the current targets for improved fuel cells. The development of improved catalysts (more efficient, longer-lived) should accelerate development of efficient fuel cells that would be commercially viable for transportation, energy production and storage, with the resultant environmental impact. In the broader sense, in addition to contributing significantly to the development of improved alloy catalysts for fuel cell cathodes, the successful coupling of computational tools including QM through ReaxFF reactive dynamics to simulation of the catalyst/support system would apply to other problems in catalysts, materials, and energy.

如果要最终克服PEM燃料电池的技术和成本限制，将取得进展，则必须对发生的反应的基本科学进行大量投资。该提案的目的是确定详细的原子机制，包括PEM燃料电池阴极氧还原反应的自由能壁垒。重点是机理和速率如何取决于合金组成，表面和大块区域之间的分布以及溶剂。计算结果将通过预测如何提高选择性，速率和寿命来测试如何提高二元和三元催化剂。此外，加利福尼亚理工学院的PIS，William A. Goddard III Boris Merinov都建议确定催化剂降解机制及其依赖合金组成的机制。结果是是一个足够准确的计算模型，可用于指导实验和工程应用。以前，仅基于第一原则，就没有实用的手段来对如此广泛的反应现象。这种新颖的方法将通过第一原理预测工程模型的数据，从而使新系统进行计算设计，然后根据实验进行测试。为了实现这一模型测试，已经与Argonne National Labs和Ford Scientific Labs安排了合作，以对那些被预测的合金进行实验。该模型应有助于开发从理论和模拟中获取的准确工程模型，但经过调整以纳入实验的结果。这种方法对于开发改进的材料和过程至关重要，以使新合金能够满足当前的靶标以改善燃料电池。改进的催化剂的发展（更有效，寿命更长）应加速有效的燃料电池的发展，这将在运输，能源生产和储存上可行，从而产生环境影响。从广义上讲，除了为改进的燃料电池阴极合金催化剂的发展做出显着贡献外，包括通过reaxff反应性动力学（包括QM）成功地耦合了催化剂/支撑系统的成功耦合，还将适用于催化剂，材料和能量中的其他问题。