CAS: Heteroatom Dimer and Cluster Catalysis

在化学系化学催化项目的支持下，亚利桑那州立大学刘静月(Jimmy)教授将研究用于重要分子化学转化的杂原子-二聚体催化剂。催化在能源、环境和可持续发展应用中发挥着重要作用。许多化学制造和排放控制过程使用昂贵的贵金属作为催化剂，以加速所需的化学反应。目前工业上使用的贵金属催化剂由于丰度低、成本高，难以持续发展。开发更有效地利用这些金属的催化剂可能会解决这一实际问题。单原子催化剂已被证明可用于各种化学反应，但仍有许多理想的化学反应不能提供最佳性能。刘教授和他的研究团队正在开发精确设计的双原子催化剂，这种催化剂可能会提供单原子催化剂无法提供的化学反应所需的增强催化性能。该项目正在研究支配催化剂催化性能的基本原则，并为其进一步开发提供设计工具，具有潜在的长期经济和环境效益的实际应用。更广泛的影响包括将研究成果纳入一年一度的高分辨率电子显微镜冬季研讨会(主要由来自美国各地的研究生参加)，培训研究生和本科生，并通过致力于向高中生提供尖端科学研究经验的科学和工程体验(SCEAM)计划指导高中生。这项由亚利桑那州立大学刘静月教授领导的研究旨在加深对支撑杂原子二聚体(例如PtPd、PtRh、PtCo、PtNi、PdCu、PtBi、PtSnn和CoCu)协同催化的基本理解。这些双原子被定位在孤立的、超小的金属氧化物岛上(例如CeOx或CoOx)，这些岛均匀地分散在高比表面积、坚固的载体上。有了这样的催化剂设计，可以预期，两个不同金属原子之间的相互作用，如果放置得很近，可以提供独特的催化性能，可以显著提高催化活性和/或提高所需反应产物的选择性。使用稳定的杂原子二聚体作为催化活性中心，不仅可以最大限度地提高金属的利用效率，还可以调节它们的催化性能，以实现所需的化学转化。这种催化剂设计策略使两个不同金属原子之间的相互作用成为可能，并为开发具有良好催化性能的稳定且定义良好的杂原子二聚体或双原子催化剂开辟了设计空间。杂原子二聚体和双原子催化剂正在接受CO氧化、水-气变换、重整和加氢反应的测试。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Chemical Catalysis program in the Division of Chemistry, Professor Jingyue (Jimmy) Liu of Arizona State University will study heteroatom-dimer catalysts for chemical transformations of important molecules. Catalysis plays a significant role in energy, environment, and sustainability applications. Many chemical manufacturing and emission control processes use expensive precious metals as catalysts to accelerate desired chemical reactions. Because of their low abundance and high cost, the current industrial precious metal catalysts are not sustainable. The development of catalysts that make more efficient use of these metals may address this practical problem. Single-atom catalysts have been demonstrated for a variety of chemical reactions, but there remain many desired chemical reactions for which these catalysts do not provide optimum performance. Professor Liu and his research team are developing precision-designed dual atom catalysts that may provide the enhanced catalytic performance needed for those chemical reactions where single-atom catalysts do not. This project is addressing fundamental principles that govern the catalytic properties of catalysts and providing design tools for their further development, with potential long term practical applications of economic and environmental benefit. Broader impacts include incorporating research results in an annual Winter Workshop of High Resolution Electron Microscopy (attended primarily by graduate students from across the US), training of graduate and undergraduate research students, and mentoring of high school students through the SCience and ENgineering Experience (SCENE) program dedicated to providing cutting-edge science research experiences to high school students.This research led by Professor Jingyue Liu of Arizona State University aims to develop a fundamental understanding of synergistic catalysis by supported heteroatom dimers ( for example PtPd, PtRh, PtCo, PtNi, PdCu, PtBi, PtSn, and CoCu). These dual atoms are localized to isolated, ultra-small metal oxide islands (for example CeOx or CoOx) which are uniformly dispersed on high-surface-area, robust supports. With such a catalyst design, it is expected that the interaction between two different metal atoms, placed in close proximity, can provide for unique catalytic properties that may significantly enhance catalytic activity and/or increase selectivity of the desired reaction products. The use of stable heteroatom-dimers as catalytically-active centers not only maximizes metal usage efficiency but also makes it possible to tune their catalytic properties for desired chemical transformations. This catalyst design strategy enables interactions between two different metal atoms and opens up design space for developing stable and well-defined heteroatom-dimer or dual-atom catalysts that possess advantageous catalytic properties. The heteroatom-dimer and dual-atom catalysts are being tested for CO oxidation, water-gas shift, reforming, and hydrogenation reactions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.