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采用共沉淀方法制备了一系列Ce-Zr-Mn复合氧化物储氧材料,并应用X射线衍射(XRD),BET,氧吸附,以及程序升温还原(TPR)对这些样品进行表征,研究了样品老化前后的结构和织构变化,储氧性能,还原性能以及物相的变化．结果表明,在Ce-Zr固溶体中掺入少量的Mn可以显著提高储氧材料的储氧能力,降低还原温度,而且均形成稳定的立方晶相的CeO_2-ZrO_2固溶体．当Mn含量(摩尔分数)达到0．025时,样品的储氧量达到最高,同时在织构上表现出优越的抗老化性能,经1273K高温老化5h后比表面积可高达57．8m~2/g．
A series of Ce-Zr-Mn composite oxide oxygen storage materials were prepared by coprecipitation method. The samples were characterized by X-ray diffraction (XRD), BET, oxygen adsorption and temperature programmed reduction (TPR) Structure and texture changes before and after aging, oxygen storage performance, reduction performance and phase changes. The results show that adding a small amount of Mn into the Ce-Zr solid solution can significantly increase the oxygen storage capacity of the oxygen storage material, reduce the reduction temperature, and form a stable cubic CeO 2 -ZrO 2 solid solution. When the content of Mn (mole fraction) reached 0.025, the oxygen storage capacity of the samples reached the maximum, meanwhile, it exhibited superior anti-aging property in texture. After aging at 1273K for 5h, the specific surface area was as high as 57.8m 2 / g.