SYNTHESIS AND PROPERTIES OF LAFEO3 ULTRAFINE POWDERS

The ultrafine LaFeO3 with particle size of 12 similar to 75nm was prepared by sol-gel method. In the process of gel to ultrafine powder, the weight loss reached 90%. The lowest forming temperature of single phase crystalline LaFeO3 ultrafine powder was ob

H-2-sensing characteristics of nanocrystalline La0.8Pb0.2FeO3 prepared by sol-gel method

Nanocrystalline La0.8Pb0.2FeO3 has been prepared by the sol-gel method. XRD patterns show that the nanocrystalline La0.8Pb0.2FeO3 is a perovskite phase with the orthorhombic structure and its mean crystallite size is about 19 nm. The influence of Pb ions which replaced the La ions on A-sites can be directly observed from the electrical and sensing properties to H-2 gas. The conductance of La0.8Pb0.2FeO3-based sensor is considerably higher than that of LaFeO3-based sensor, and Pb-doping can enhance the sensitivity to H2 gas. An empirical relationship of R = KCH2alpha with alpha = 0.668 was obtained.

静电纺丝法制备LaFeO_3微纳米纤维

采用静电纺丝技术并结合溶胶-凝胶方法制备了LaFeO3微纳米纤维.用差热-热重分析(TG-DTA)、X射线衍射(XRD)、红外光谱(FTIR)、X射线光电子能谱和场发射扫描电镜(FE-SEM)对样品进行了表征.实验结果表明,390℃时钙钛矿结构的LaFeO3晶体开始形成,同时伴有少量微弱的La2O2CO3和Fe2O3杂相存在,600℃煅烧获得正交钙钛矿结构的LaFeO3微纳米纤维,其纤维直径分布在300~600 nm之间,其平均直径约为420 nm,平均晶粒尺寸为28 nm.