| Using catalysts to purify automotive exhaust gas has more and more been regarded by human society. It is generally accepted that the most important factor in the catalyst is the oxygen storage materials, which have a direct relation to the puring performance. In present paper, the influence of additives and preparation methods on the performance of oxygen storage materials was studied in detail. Oxygen pulse technique, XRD, H2-TPR, and BET surface area analysis methods were used to characterize the oxygen storage capacity (OSC), textual property, reduction behavior and surface area of the materials above respectively.The results indicate that the OSC and reductibility of the CeO2-ZrO2 solid solution are not improved after adding E ions. While after incorporating M ions into the CeO2-ZrO2, the samples exhibit high OSC probably by reason that M-O itself also has good capability of oxygen adsorption. After aged at high temperature, the OSC of these samples decreased dramatically for the formation of M2O3 and MO2 and for the separation of tetragonal phase of CeO2-ZrO2.The appropriate addition of polymers into oxygen storage materials can improve the OSC obviously and can make the samples become high-temperature-resistant materials with favorable surface area even after aged at high temperature. When 20%(wt) PolymerB was added, the oxygen storage materials get the most ideal synthesis properties.The materials prepared by various methods show different properties. The studies imply that the samples prepared by sol-gel method have the highest OSC and special surface area, but after calcinated at 1000? for 2h, the OSC and special surface area decreased sharply, meaning a bad thermal stability. The OSC and special surface area of the samples prepared by precipitation keep very well after aged, exhibiting a promising thermal resistance. While the samples prepared by dipping method have a much more stable OSC at different temperature, that is, they have a good thermal stability.
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