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

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

1554112 Christopher, Phillip Promoting Catalytic Reactions Via Isolated Metal Atoms Supported 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.