Probing metal catalyst-support interactions using small cluster models: Gas-phase reactivity studies, anion photoelectron spectroscopy, and DFT calculations

化学催化项目支持来自印第安纳大学的Caroline C. Jarrold教授的努力，研究电子和结构特性之间的相互作用，这些良好定义的簇模型用于研究催化剂-载体和催化剂-载体-底物相互作用的固有局部现象。一种三管齐下的方法被用于表征新催化剂的簇模型，这些催化剂已被确定为对工业上重要的水气转换反应特别活跃。（水气转换反应催化水和一氧化碳结合，产生二氢和二氧化碳。）对模型团簇的阴离子光电子（PE）光谱测量提供了团簇作为金属成分和氧含量函数的质量特异性电子谱。通过将实验PE光谱与计算结果相协调来确定团簇结构，并且对团簇的气相反应性研究允许团簇反应性与团簇分子和电子结构之间的相关性。第一个系列的研究集中在含铂的星团系统受到最近的文献启发。还探索了具有类似（可能改进的）属性的替代和更便宜的集群模型，并将其与已知的工业催化剂进行了比较。这些研究的广泛影响包括为设计用于水煤气转换反应的改进、低成本和更节能的催化剂提供知识，以及评估用于研究非传统氧化态金属氧化物的新计算方法。此外，新一代科学家接受培训，了解工业相关的催化反应。金属氧化物常被用作工业催化剂。它们的组成通常经过优化，以便催化剂在更低的温度下或使用更便宜、更容易获得的材料。本研究项目旨在确定控制水气转换反应中使用的催化剂的基本分子尺度特征。水气转换反应将水和一氧化碳结合，生成二氢和二氧化碳。实验和计算工具用于创建和研究在工业上重要的反应中使用的定义良好的纳米和亚纳米级金属氧化物的性质。这个项目的更广泛的技术影响包括减少这个工业过程的能源消耗。这个项目的一个更直接和直接的成果是利用计算和实验平台对青年男女进行科学方法方面的培训，其中心是一个由实际工业问题推动的项目。

The Chemical Catalysis Program supports the efforts of Professor Caroline C. Jarrold from Indiana University to study the interplay between electronic and structural properties of well-defined cluster models used to study the inherently local phenomenon of catalyst-support and catalyst-support-substrate interactions. A three-pronged approach is used to characterize cluster models of new catalysts that have been identified as particularly active toward the industrially-important water-gas shift reaction. (The water gas shift reaction catalytically combines water and carbon monoxide to produce dihydrogen and carbon dioxide.) Anion photoelectron (PE) spectroscopy measurements on model clusters provide a mass-specific electronic profile of the clusters as a function of both metal composition and oxygen content. Cluster structures are determined by reconciling experimental PE spectra with computational results and gas-phase reactivity studies on the clusters allow for the correlation between cluster reactivity and cluster molecular and electronic structures. The first series of studies focus on platinum-containing cluster systems inspired by recent literature. Alternative and less expensive cluster models rationalized to have similar (and possibly improved) attributes are also explored and compared to known industrial catalysts. The broader impacts of these studies include the generation of knowledge that can inform the design of improved, lower-cost and more energy-efficient catalysts for water gas shift reactions and the evaluation of new computational approaches used to study metal oxides in non-traditional oxidation states. In addition, a new generation of scientists are trained to understand industrially-relevant catalysis reactions.Metal oxides are often used as industrial catalysts. Their composition is often optimized so that the catalysts operate at lower temperatures or with cheaper and more readily available materials. This research project is designed to determine the essential molecular-scale features that govern catalysts used in the water gas shift reaction. The water gas shift reaction combines water and carbon monoxide to make dihydrogen and carbon dioxide. Experimental and computational tools are used to create and study the properties of well-defined nano- and sub-nanometer scale bits of metal oxides used in this industrially important reaction. The technical broader implications of this project include a reduced energy consumption for this industrial process. A more immediate and direct outcome of this project is the training of young women and men in the scientific method using computational and experimental platforms centered on a project that motivated by practical industrial concerns.