Strontium-doped perovskites rival platinum catalysts for treating NOx in simulated diesel exhaust

Science. 2010 Mar 26;327(5973):1624-7. doi: 10.1126/science.1184087.

Abstract

The high cost and poor thermal durability of current lean nitrogen oxides (NOx) aftertreatment catalysts are two of the major barriers to widespread adoption of highly fuel-efficient diesel engines. We demonstrated the use of strontium-doped perovskite oxides as efficient platinum substitutes in diesel oxidation (DOC) and lean NOx trap (LNT) catalysts. The lanthanum-based perovskite catalysts coated on monolith substrates showed excellent activities for the NO oxidation reaction, a critical step that demands heavy usage of platinum in a current diesel aftertreatment system. Under realistic conditions, La(1-x)SrxCoO3 catalysts achieved higher NO-to-NO2 conversions than a commercial platinum-based DOC catalyst. Similarly, a La(0.9)Sr(0.1)MnO3-based LNT catalyst achieved NOx reduction performance comparable to that of a commercial platinum-based counterpart. The results show promise for a considerably lower-cost diesel exhaust treatment system.

Publication types

  • Research Support, Non-U.S. Gov't