丙烯酸法制备La_(0.75)Sr_(0.25)MnO_3纳米粉体

采用丙烯酸法合成了La0.75Sr0.25MnO3(LSM)纳米粉体,探讨了合成过程中丙烯酸与交联剂用量、热处理温度等合成条件对合成粉末的物相与形貌的影响,对合成的粉末进行了XRD、SEM、TG-DTA、FTIR分析.结果显示:在丙烯酸:交联剂:LSM粉末质量比为0.3:0.03:1,热处理温度为950℃的条件下,可得到单相、高纯、均匀、少团聚的LSM纳米粉末;电性能测试表明,LSM烧结体在700℃附近电导率达到较高值(约180 S·cm-1).可见,这种新颖的丙烯酸法较其他化学法更绿色环保,制备的粉体电学性能优异,适合用于SOFC单电池阴极.

Synthesis of La0.75Sr0.25MnO3 Nano-powder Prepared via Route of Acrylic Acid as Complexing Agent

La0.75Sr0.25MnO3（LSM） nanocrystalline powders are prepared by a modified sol-gel process using acrylic acid as complexing agent. The influence of the amount of acrylic acid and cross-linker, the calcination temperature on the structure and morphology of the LSM powders is studied. The resultant powders are characterized by conducting XRD, SEM, TG-DTA and FTIR analysis. It is shown that the morphology and structure of the oxide particles are significantly dependent on the preparation conditions. High purity, single phase, homogenous, nanocrystalline LSM powders with slight aggregation are obtained after sintering at 950℃under the optimized ratio of acrylic acid：cross-linker：resultant powder weight being 0.3：0.03：1. The conductivity of the sintered LSM sample prepared from the nanocrystalline powders is measured for about 180 S＆#183;cm-1 in air at 700℃. The results indicate that the proposed acrylic acid method is environmentally greener and has better electrical properties than other chemical methods. Thus, it is suitable for mass synthesis of LSM powders for the cathode of single battery in SOFC.