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采用共沉淀法制备了一系列Nd2O3含量为0～13wt%的CeO2-ZrO2-A12O3(CZA)复合氧化物,并通过X射线衍射(XRD)、低温N2吸附–脱附、氧脉冲吸附(OSC)、H2–程序升温还原(H2-TPR)及扫描电子显微镜(SEM)等方法对所制备的材料进行了表征.研究结果表明,Nd2O3在CZA固溶体中的溶解限约为10wt%,过量Nd的添加会出现分相形成Nd0.5Ce0.5O1.75氧化物.掺杂适量Nd能有效抑制氧化物晶粒的长大,提高材料的热稳定性和氧化还原性能.Nd2O3的掺杂量为10wt%时,样品的织构稳定性最好,1000℃老化5 h后,比表面积和孔容分别达97.14 m2/g和0.44 mL/g.Nd2O3的掺杂量为7wt%时,样品有高的储氧量,经600℃和1000℃焙烧后储氧量分别为938.01μmol/g和821.72μmol/g;体相氧的移动能力最强,还原性能最佳,老化后还原峰温由465℃升高到483℃.SEM结果表明,所制备的材料均为球形颗粒,Nd2O3的添加可以有效阻止高温焙烧过程中粒子的团聚.
A series of CeO2-ZrO2-A12O3 (CZA) composite oxides with Nd2O3 content of 0-13wt% were prepared by coprecipitation method and characterized by XRD, N2 adsorption-desorption, OSC, , H2-temperature-programmed reduction (H2-TPR) and scanning electron microscopy (SEM) were used to characterize the prepared materials.The results show that the dissolution limit of Nd2O3 in CZA solid solution is about 10wt% Will appear in phase to form Nd0.5Ce0.5O1.75 oxide.Doping appropriate amount of Nd can effectively inhibit the growth of oxide grains and improve the thermal stability and redox properties of the material.When the doping amount of Nd2O3 is 10wt% , The texture stability of the sample is the best, and the specific surface area and pore volume are 97.14 m2 / g and 0.44 mL / g respectively after being aged at 1000 ℃ for 5 h.When the content of Nd2O3 is 7wt%, the samples have high oxygen storage , The oxygen storage capacity after calcination at 600 ℃ and 1000 ℃ was 938.01μmol / g and 821.72μmol / g, respectively. The bulk oxygen possessed the strongest ability to move and the best reduction performance. After the aging, the peak temperature decreased from 465 ℃ to 483 ℃ .SEM results show that the prepared materials are spherical particles, Nd2O3 addition can effectively prevent the high temperature calcination process particle agglomeration.