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Stricter regulatory standards are continuously adopted worldwide to control heavy duty emissions, and at the same time, fuel economy requirements have significantly lowered exhaust temperatures. The net result is a significant increase in Precious Group Metal (PGM) usage with current Diesel Oxidation Catalyst (DOC) technology. Therefore, the design and development of advanced DOC with ultra-low PGM to achieve highly beneficial emission performance improvement is necessary. The advanced DOC is synergized PGM (SPGM) with Mixed Metal Oxide (MMO). The presence of MMO in SPGM is responsible for NO oxidation to NO2 which is critical for the passive regeneration of the downstream filter and SCR function. This paper outlines the development of MMO for application in modern DOCs and addresses some specific challenges underlying this application. Lab and flow reactor data demonstrates MMO by itself owns great oxidation properties with high surface area available for NO oxidation reaction.

In the context of evolving market conditions, the three-way catalyst (TWC) design is entering an exciting new phase. It remains the main emission control strategy for gasoline powered vehicles; in the meantime a rapid period of evolving engine developments, the constrained tailpipe regulations and the material supply issues present a unique challenge to the catalyst developers. A key approach here is to achieve highly beneficial emission performance based on the ultra-low PGM levels. In this regard, we mainly focus on the materials design and have developed the advanced spinel oxides for zero precious metals (ZPGM) and synergized precious metals (SPGM) TWCs. These advanced spinel materials showed improved thermal stability compared to that of PGM based standard materials. Fundamental studies on the microstructure of spinel oxide with newly developed composition confirm the aging stability.