Preparation of ceria-zirconia sub-catalysts for automotive exhaust cleaning

This paper focuses on the development of ceria-zirconia materials which hav e high thermal stability and high catalytic activity. The CeO2-ZrO2 system is very important as a sub-catalyst in the autoexhaust catalytic converters , especially on the oxygen-storage capacity (OSC). The role of the CeO2-ZrO 2 is to adjust the air-fuel ratio to the stoichiometric value to attain the simultaneous conversions of the three main pollutants such as CO, NOx and hydrocarbons, by providing and absorbing oxygen during fuel-rich and fuel-l ean conditions, respectively. In this article, recent advances in the desig n and development of the sub-catalysts in the autoexhaust catalytic convert ers are reviewed. (C) 2000 Elsevier Science S.A. All rights reserved.