GOALI: Sinter-Resistant, Self-Regenerating Platinum Group Metal Catalysts for Low Temperature Oxidation

项目名称：目标：用于汽车排气处理的耐烧结、自再生铂族金属催化剂为满足我们的运输需求而开发的先进内燃机通过降低排气温度来提高燃油效率。 这对催化转化器的技术提出了要求，因为这些催化剂必须在较低的温度下变得活跃。 拟议的研究涉及这些催化剂的设计，从而改善空气质量和社会对能源的需求。 汽车尾气催化剂在使用过程中由于贵金属烧结而失去活性。这种性能损失需要新的排气催化剂，从而对贵金属如Pt和Pd的价格施加压力。 通过开发减缓金属颗粒尺寸增长的方法，减少了对这些贵金属的需求，并且可以更有效地使用它们。这个GOALI奖承认这项研究对美国的战略重要性，并支持新墨西哥州大学的Abhaya Datye与通用汽车全球研发部的Chang Kim和Gongshin Qi之间的产学合作。 大学参与者将使用模型催化剂，允许使用先进的显微镜技术进行表征，这些技术无法应用于实际的商业汽车催化剂。研究结果将与通用汽车的科学家分享，该团队将尝试将研究结果应用于废气排放控制的新技术中。作为该合作研究计划的一部分，学生将在行业合作伙伴实验室工作，这是一个额外的教育功能。这里所解决的研究挑战影响了用于满足能源，材料和燃料需求的整个贵金属多相催化剂类别。 汽车尾气中的三效催化剂（尤其是处于紧密耦合位置的那些）经受升高的温度，这导致纳米颗粒尺寸的增长和活性的损失。 该研究将解决纳米颗粒的奥斯特瓦尔德熟化，通过使用模型催化剂研究原子发射和捕获的关键步骤。 工业负载型金属催化剂本身不适合于直接测量过程，如原子发射或捕获，这对理解催化剂烧结至关重要。 该研究计划使用新型的模型催化剂，可以加热到汽车尾气中遇到的温度和气体气氛。 模型催化剂允许获得样品的相同区域的时间推移的电子显微图像，从而可以推断出原子传输速率。 这些速率，再加上一个强大的基于物理的模型，将有助于改善催化剂烧结的预测。 将制定方法来改变排放率，并制定新的办法来捕获移动的物种。 使用模型催化剂开发的概念将转化为粉末催化剂，并使用行业合作伙伴的设施在现实条件下进行测试。工业界和大学研究人员的密切参与对于验证概念和模型至关重要。 通用汽车公司在人员时间和设施使用方面投入了大量资源，以使这项研究取得成功。 该合作伙伴关系将有助于解决催化剂烧结理解中的重大未知因素，并将导致具有改进反应性的新型催化剂合成的进展。

Project Title: GOALI: Sinter-Resistant, Self-Regenerating Platinum Group Metal Catalysts for Automotive Exhaust TreatmentAdvanced combustion engines being developed for meeting our transportation needs achieve improved fuel efficiency by lowering exhaust temperatures. This puts demands on the technology for catalytic converters, since these catalysts must become active at lower temperatures. The proposed research addresses the design of these catalysts, leading to improvements in air quality and to societal needs for energy. Automotive exhaust catalysts lose activity during use due to precious metal sintering. This loss of performance requires a new exhaust catalyst, thereby putting pressure on prices for precious metals such as Pt and Pd. By developing ways to slow the growth of metal particle size, demand for these precious metals is reduced, and they can be used more efficiently. This GOALI award recognizes the strategic importance of this research to the U.S., and is in support of an industry-university collaboration between Abhaya Datye of the University of New Mexico and Chang Kim and Gongshin Qi of General Motors Global R&D. The university participants will use model catalysts that allow characterization with advanced microscopy techniques which cannot be applied to actual commercial automotive catalysts. The results will be shared with the scientists at GM, and the team will attempt to implement the findings in new technologies for exhaust emissions control. An added educational feature is that students will spend time working in the industry partner laboratories as part of this collaborative research program.The research challenge being addressed here impacts the entire class of precious metal heterogeneous catalysts used for meeting the needs for energy, materials and fuels. Three way catalysts in automotive exhaust (especially those in the close coupled position) are subjected to elevated temperatures that lead to growth of nanoparticle size and loss of activity. The research will address Ostwald ripening of nanoparticles, investigating the key steps of atom emission and capture, by using model catalysts. Industrial supported metal catalysts do not lend themselves to direct measurements of processes such as atom emission or capture, which are critical to understanding catalyst sintering. This research program uses novel forms of model catalysts that can be heated to temperatures and gas atmospheres encountered in automotive exhaust. The model catalysts allow obtaining time-lapsed electron micrographic images of the same region of the sample, so that rates of atom transport can be inferred. These rates, coupled with a robust physics-based model, will help improve predictions of catalyst sintering. Methods will be developed to modify the rates of emission and novel approaches developed to capture mobile species. Concepts developed using model catalysts will be translated to powder catalysts and tested under realistic conditions using the facilities of the industry partner. The close participation of industry and university researchers is critical for validating the concepts and models. GM has committed significant resources in terms of people time and access to facilities, to enable this research to be successful. The partnership will help address significant unknowns in the understanding of catalyst sintering, and will lead to advances in the synthesis of novel catalysts with improved reactivity.