纳米Ce_(0.8)Gd_(0.2)O_(2-δ)粉体的制备与低温烧结  

Synthesis and Low Temperature Sintering of Nanocrystalline Ce_(0.8)Gd_(0.2)O_(2-δ)

作　　者：梁金[1] 朱庆山[1] 

机构地区：[1]中国科学院过程工程研究所多相反应实验室,北京100080

出　　处：《过程工程学报》2005年第6期688-692,共5页The Chinese Journal of Process Engineering

基　　金：国家863计划资助项目(编号:2003AA323010)

摘　　要：采用正丁醇共沸蒸馏,对碳酸氢氨共沉淀法合成Ce0.8Gd0.2O2-δ(GDC)的前驱体羟基碳酸盐进行脱水处理,以减少合成粉体的团聚.前驱体及煅烧后粉体的性能用XRD,TG-DSC,BET,FESEM表征.经共沸蒸馏处理的前驱体600℃煅烧2h后比表面积达到49.0m2/g,比未经共沸蒸馏处理的高.煅烧得到的GDC粉体的烧结性能用非等温烧结与等温烧结实验进行表征,并与未共沸蒸馏处理的粉体进行比较.结果表明,对碳酸氢氨共沉淀的前驱体进行共沸蒸馏脱水预处理,可提高粉体的烧结活性,粉体在1100℃烧结10h后实现完全致密化,相对密度大于98%.Reactive nanocrystalline Ce0.8Gd0.2O2-δ （GDC） nanopowder has been successfully synthesized via a modified carbonate coprecipitation method. Azeotropic distillation treatment was applied to dry the carbonate precipitates, where the dehydration process was proved to be effective to alleviate hard agglomerate formation during high temperature calcination, as confirmed by the BET and FESEM characterizations. The results showed that after calcination at 600 ℃, the powder from the precursor with the azeotropic distillation treatment has a specific surface area of 49.0 m^2/g, which is substantially higher than that of the powder from the precursor without the azeotropic distillation treatment. Smterting behavior of these two kinds of powder was investigated via dilatometry and isothermal sintermg, and revealed that the powder from the precursor with the azeotropic distillation treatment showed better sintermg activity, where uniaxiully pressed compacts were sintered to over 98% of theoretical density at 1100 ℃ for 10 h. The superior smterability was mainly attributed to the fact that azeotropic distillation treatment reduced the tendency of hard agglomeration formation for the as-synthesized powders, which allows to form green compacts m high green density with high homogeneity.

关 键 词：Ce0.8Gd0.2O2-δ 共沸蒸馏2005-12-19烧结 纳米晶粒 

分 类 号：TG148[一般工业技术—材料科学与工程]