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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.

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A series of lithium-based lean-burn NO x trap catalysts Pt/Li/TiO 2 -Al 2 O 3 were prepared by sequential impregnation. The doping of TiO 2 into the support Al 2 O 3 significantly enhances the sulfur-resistance performance of the catalyst Pt/Li/Al 2 O 3 . On TiO 2 -Al 2 O 3 mixed oxides, the Pt and lithium species are more highly dispersed, giving higher NO x storage capacity, as compared with those on Al 2 O 3 and TiO 2 . In situ DRIFTS reveals that the NO x storage on Pt/Li/TiO 2 -Al 2 O 3 mainly proceeds on -OLi sites forming bidentate nitrate species at 500°C. The catalyst Pt/Li/TiO 2 -Al 2 O 3 with 40% TiO 2 in the support is the most promising one applicable to the lean-burn NO x abatement.