【摘 要】
：
Cerium zirconium-based(CZ)oxygen storage materials(OSMs)play a crucial role in three-way catalysts(TWCs),while CZ needs to be modified to satisfy more rigorous
【机 构】
：
National Engineering Research Center for Rare Earth Materials,GRINM Group Corporation Limited,Beijin
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Cerium zirconium-based(CZ)oxygen storage materials(OSMs)play a crucial role in three-way catalysts(TWCs),while CZ needs to be modified to satisfy more rigorous emission standard.In this study,tran-sition metal(TMs＝Mn,Cr,Fe,Cu)oxides modified CZ were prepared by incipient wetness impregnation method to improve the oxygen storage capacity of CZ-based materials.To clearly illustrate the influence of TM oxides,N2 adsorption-desorption,X-ray diffraction(XRD),oxygen storage capacity(OSC),tem-perature programmed reduction by H2(H2-TPR)and X-ray photoelectron spectroscopy(XPS)were used to characterize the physical and chemical properties of samples.It is found that,all modified CZ have higher OSC,lower reduction temperatures than those of pristine CZ.Interaction between TMOs and CZ take precedence over specific surface to influence OSC.Notably,FeOx/CZ has the highest OSC,which is about 1.9 times that of CZ and it could be attributed to synergistic effect between FeOx and CZ; CuOx/CZ has the lowest reduction temperature which is 168 C lower than that of CZ,and it can be explained by hydrogen spillover effect.
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