Oxygen Store and Release of CeO_2-ZrO_2-MO_(1.5) (M = La,Nd) Powders Prepared by Co-Precipitation Method

摘要

CeO_2-ZrO_2-MO_(1.5) (M = La,Nd) powders to be used as three way catalysts for automotive exhaust gases were prepared from nitrate solutions by co-precipitation method.As a catalyst exposed to high temperature gas,a high thermal stability is required to keep high surface area.High oxygen storage capacity is also required.In this study,their oxygen storage capacity (OSC) ,surface area (SA) and temperature programmed reduction behavior (TPR) of CeO_2-ZrO_2-MO_(1.5) powders were measured.The substitution of ZrO_2 by MO_(1.5) increased the OSC value at calcination temperature 1000 C.SA values decreased as the calcination temperature increased,and SA was suppressed by the addition of MO_(1.5).In both cases,the effect of LaO_(1.5) addition was higher than that of NdO_1.5.