In-situ infrared spectroscopy of base metal catalysts for automotive applications

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Eliminating precious metals in catalytic converters is a highly sought-after goal in the automotive industry.Catalytic converters consist of a ceramic plug that is coated with a catalyst layer. The plug is incorporated intothe exhaust system of an automobile and is used to passively convert carbon monoxide, unburnedhydrocarbons, and nitrogen oxides into less toxic products like carbon dioxide, water, and diatomic nitrogen.The current generation of catalyst materials use precious metals like platinum, palladium, and rhodium toaccomplish the reduction and oxidation reactions at temperatures of several hundred degrees Celsius. Thedevelopment of catalysts made from earth abundant metals like iron, cobalt, copper, and magnesium wouldprovide a significant reduction in the cost of a catalytic converter. However, a major challenge to thewidespread application of base metal catalysts is the harmful effect of water and extended aging on theefficiency of the catalyst. Understanding the mechanistic details of water adsorption/desorption and theformation of metal hydroxides is critical in the design of more robust materials. Moreover, a clearunderstanding of the chemical composition and crystal structure of high performance catalyst materials isimportant in the development of intellectual property. In order to address these challenges, we will performinfrared spectroscopy on base metal catalysts that were prepared and tested under different conditions, andthrough careful analysis of the resulting spectra, identify key chemical components that either harm or help theefficiency of the catalyst material. In addition, we will watch material aging in real time and monitor reactants,products, and any intermediates as the catalysts perform reactions at several hundred degrees Celsius using ahome-built in-situ infrared spectroscopic experiment.