Thermally Induced Deactivation and the Corresponding Strategies for Improving Durability in Automotive Three-Way Catalysts

Abstract

Increasingly demanding exhaust emissions regulations require that automotive three-way catalysts (TWC) must exhibit excellent catalytic activity and durability. Thus, developing TWC based on an accurate understanding of deactivation mechanisms is critical. This work briefly reviews thermally induced deactivation mechanisms, which are the major contributor to deactivation, and provides an overview of the common strategies for improving durability and preventing deactivation. It highlights the interaction of metals with supports and the diffusion inhibition of atoms and crystallites in both washcoats and metal nanoparticles and concludes with some recommendations for future research directions towards ever more challenging catalyst manufacture to meet increasing durability requirements both now and in the future.

Recent advances in gasoline three-way catalyst formulation: A review

“…During this start-up period, the low engine exhaust temperature (typically \ 250°C) only slowly raises the temperature of the catalyst itself. 9 However, good conversions are typically only achieved at temperatures . 300°C.…”

Atomic Layer Deposition on Porous Materials: Problems with Conventional Approaches to Catalyst and Fuel Cell Electrode Preparation

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In Situ Investigations on the Facile Synthesis and Catalytic Performance of CeO2-Pt/Al2O3 Catalyst

“…Platinum-based catalysts have been widely used in the chemical industry for the catalytic dehydrogenation of light alkanes, such as ethane and propane [1,2], as well as the automotive industry to catalytically oxidize harmful pollutants, including CO, NO, and hydrocarbons [3][4][5][6]. Ceria has been used in automotive catalysts, due to its oxygen storage capacity and the ability to stabilize active metals [7][8][9]. The recognized ability of ceria to undergo rapid reduction/oxidation cycles (4CeO 2 2Ce 2 O 3 + O 2 ) plays a significant role in providing oxygen mobility and oxygen storage/release [8].…”

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