Abstract: CeO2-ZrO2 solid solution is an indispensable oxygen storage material for the three way catalyst to control the pollution gas emission from automobiles. In this paper, three series of Ce-Zr-Al nanocomposite(ACZ) was prepared by citrate acid sol-gel method, sol assistant co-precipitation and sol co-precipitation, respectively. The obtained samples were calcinated at 1000 ℃ for 4 h to test the thermal stability and oxygen storage capacity(OSC). The effect of synthetic methods on these properties was investigated by means of X-ray diffraction(XRD), Brunauer Emmett Teller(BET) specific surface area(SSA) and H2 temperature-programmed reduction(H2-TPR). The results revealed that the thermal stability and oxygen storage capacity of all the ACZ were improved compared to the pure CeO2-ZrO2 solid solution. The molar proportion of Al doped in ACZ is 5, 10, 5 for citrate acid sol-gel method, sol assistant co-precipitation and sol co-precipitation, respectively. ACZ prepared by citrate acid sol-gel method had the highest oxygen storage capacity(717.5 μmol/g-CeO2), account for 49.3% of the theoretical maximum.

Key words: Ce-Zr solid solution, nanocomposite, thermal stability, sol-gel method, oxygen storage capacity