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The present work investigates the catalytic performances of two types of CeO2 (S,I) NOxstoragecatalysts at low temperatures (≤300℃),where 2 wt.%Pt/Al2O3 was mechanically blended in.The interests were concentrated on the difference between these two CeO2 for the physical-chemical properties and lean NOx trapping capacity.XRD,BET and SEM were used to characterize the physical properties.XPS and H2-TPR were used to characterize the surface Ce3+ concentration and the surface-active oxygen.DRIFTS were used to characterize the NOx adsorbed species.CeO2-S catalyst presents outstanding NOx trapping capacity and higher thermal stability than CeO2-I catalysts,and CeO2-S catalysts present richer physical properties and higher content of active [O] species.The interaction between Pt/Al2O3 and CeO2-S results in easier surface oxygen utilization of CeO2 and more NO2 formation,which benefits for the NOx trapping process at low temperature.Direct loading Pt on aged CeO2 supports can enhance the NO2 formation and improve NOx adsorbed species formation and NOx trapping capacity,which is comparable with fresh CeO2 catalysts.