CAREER: Supports as steric and electronic modifiers of catalysis at single atom metal active sites

1554112 Christopher，Philli通过孤立的金属原子促进催化反应支持的金属催化剂，特别是那些使用昂贵的贵金属(如Rh)的催化剂，当贵金属以极小的颗粒分散时通常是最有效的-在有限的情况下，作为孤立的金属原子。这项研究从根本上考察了如何设计支持氧化物材料和活性贵金属之间的相互作用，以控制孤立的Rh原子的稳定性和活性。这项工作的成果将被用于设计丙烯氢甲酰化反应的高选择性催化剂--这是一种重要的工业反应，目前在均相液相催化条件下操作。一种异质的气相模拟物--就像这里所寻求的--将提供一种成本更低、环境友好的替代方案。此外，这项研究将为加州大学河滨分校广泛的学生群体提供机会，发展成功的技术职业所需的分析和沟通技能。该项目重点控制孤立金属原子催化剂的选择性、反应性和稳定性，方法是改变氧化物载体，并通过创建电子和空间结构来复制单金属原子均相催化剂的电子和空间结构。这项研究的中心是一系列涉及合成、原位催化剂转化和分析方法的技术，这些方法将被用来创建、确认和表征孤立的原子位置，并控制它们的活性和稳定性。基础实验将使用探针分子光谱、探针反应动力学、原位光谱和显微镜以及密度泛函理论计算进行。虽然目前的重点将是丙烯氢甲酰化，但相关的基本理解将通过设计比均相工艺更节能、更环保的多相催化工艺来造福社会。该项目的高度多学科性质将为这个拉美裔服务机构的学生提供大量机会，让他们发展基于精心推理和结构化的科学论证来展示技术信息的技能。

1554112 Christopher, PhillipPromoting Catalytic Reactions Via Isolated Metal AtomsSupported metal catalysts, especially those utilizing expensive noble metals such as rhodium (Rh), are often most effectively utilized when the noble metal is dispersed as extremely small particles - and in the limit as isolated metal atoms. This study examines at a fundamental level how interactions between the supporting oxide material and the active noble metal can be engineered to control the stability and activity of isolated Rh atoms. Insights from the work will be used to design catalysts with high selectivity in propylene hydroformylation - an important industrial reaction currently operated under homogeneous liquid-phase catalytic conditions. A heterogeneous, gas-phase analog - as sought here - would offer a lower cost, environmentally friendly alternative. Additionally, the research will provide opportunities for a broadly diverse student body at UC Riverside to develop both the analytical and communication skills needed for successful technical careers.The project focuses on controlling the selectivity, reactivity, and stability of isolated metal atom catalysts by varying the oxide support and by functionalizing the support with organosilane moieties in ways that create electronic and steric structures that replicate those of single-metal-atom homogeneous catalysts. Central to the study are a host of techniques involving synthesis, in-situ catalyst transformations, and analytical methods that will be utilized to create, confirm, and characterize the isolated atom sites and control their activity and stability. Fundamental experiments will be carried out using probe molecule spectroscopy, probe reaction kinetics, in-situ spectroscopy and microscopy, and density functional theory calculations. While the immediate focus will be on propylene hydroformylation, the associated fundamental understanding will benefit society through the design of heterogeneous catalytic processes that are more energy and environmentally friendly than homogeneous processes. The highly multidisciplinary nature of the project will provide plentiful opportunities for students at this Hispanic serving institution to develop skills in presenting technical information based on carefully reasoned and structured scientific arguments.