尿素均相沉淀法制备纳米粉体Ce0.8Sm0.2O1.9的烧结性能

摘要

Sm3+ doped CeO2 powders (SDC) were prepared by homogeneous precipitation method using Sm2O3 and Ce(NO3)3·6H2O as the raw materials and CO(NH2)2 as the precipitant. The evolution behavior of the precursor in the heating process and the properties of the SDC powders were characterized by TG-DTA, XRD, SEM and BET method,respectively. The effects of calcination temperature on the grain size and sinterability of the SDC powders were studied.The results show that the average grain size increases with increasing temperature. The precursor calcined at 700 ℃ is asingle cubic fluorite-type structure with nearly spherical shape and weakly aggregated. The grain size of the powder is 15 nm. In addition, the SDC powders have good sinterability in the experiment and the sintered specimens with relative density up to over 95％ and average grain size of 0.6 μm can be manufactured at 1 400 ℃ for 2 h under simply processing conditions.%以尿素为沉淀剂,Sm2O3和Ce(NO3)3·6H2O为起始原料,采用均相沉淀法制备Sm3+掺杂CeO2基纳米固溶体Ce0.8Smo.2O1.9(SDC).利用TG-DTA、XRD、SEM和BET等手段对前驱体的热分解行为和SDC粉体的性能进行表征,研究焙烧温度对SDC粉体粒径和烧结性能的影响.结果表明:随焙烧温度的升高,晶粒尺寸逐渐增大;700℃焙烧的前驱体是具有良好结晶性能的类球形萤石型结构固溶体,晶粒尺寸为15 nm,粒子间仪有较弱的软团聚;该粉体具有较好的成型和烧结性能,将素坯在1 400℃保温2 h,得到相对密度高于95%、平均粒径约为0.6 μm的固体电解质陶瓷体.