文献类型：期刊文献

中文题名：强制混合共沉淀法制备纳米Mn_xFe_(1-x)O_4粒子及结构表征

英文题名：Preparation and Characterization of Mn_xFe_(1-x)O_4 Nanoparticles Coprecipitated with Forced Mixing

作者：朱以华[1];胡英[2];罗美芳[1]

机构：[1]华东理工大学超细材料制备与应用教育部重点实验室,上海200237;[2]华东理工大学化学系,上海200237

年份：2004

卷号：4

期号：3

起止页码：233

中文期刊名：过程工程学报

外文期刊名：The Chinese Journal of Process Engineering

收录：CSTPCD;;EI(收录号：2004348325261);Scopus;北大核心:【北大核心2000】；CSCD:【CSCD2011_2012】；

基金：国家自然科学基金资助项目(编号:20276019)

语种：中文

中文关键词：MnxFe1-xO4;共沉淀;Rietveld精修;阳离子分布;磁性能

外文关键词：Mn_xFe_(1-x)O_4; coprecipitation; Rietveld refinement; cation distribution; magnetic properties

摘要：采用强制混合共沉淀方法制备了纳米MnxFe1-xO4粒子.磁性能测试显示,随着Mn含量的增加,产物粒子比饱和磁化强度开始略有下降,而后增加.这与粒子粒径的变化趋势一致.TEM照片显示MnFe2O4的粒径大于Fe3O4的粒径.Rietveld结构精修显示MnFe2O4样品的阳离子分布为Mn0.3Fe0.7[Mn0.7Fe1.3]O4.MnFe2O4样品比Fe3O4样品的氧参数u和A位间隙都大.其平均晶粒大小和微应变也比Fe3O4样品的大.这可能与Mn2+离子的离子半径较大、占位分布处于亚稳态有关.氧化过程的热分析显示MnFe2O4样品氧化增重的温度高于Fe3O4样品.DTG对应的最大增重温度分别为243.7和358.1oC,表明其抗氧化的稳定性增加.
MnxFe1-xO4 nanoparticles were prepared by coprecipitation with forced mixing. The measurement of magnetic properties indicated that with increasing Mn concentration the specific saturation magnetization of the MnxFe1-xFe2O4 samples decreased at first, and then increased again. The variational trend was also found in estimating particle size. The observation of TEM showed that the size of MnFe2O4 particles was larger than that of Fe3O4 particles. The calculation of Rietveld refinement suggested that the cation distribution of the MnFe2O4 sample was Mn0.3Fe0.7[Mn0.7Fe1.3]O4, and the oxygen parameter and the tetrahedral interstices of the MnFe2O4 sample were larger than those of Fe3O4 sample. The crystallite size and the microstrain of the MnFe2O4 sample were also larger than those of Fe3O4 sample, probably due to its larger ion radius and the metastable cation distribution. The thermal analysis of sample oxidation showed that the temperature for weight gaining from oxidation of the MnFe2O4 sample was higher than that of Fe3O4 sample. The temperature for maximum increase in weight shown in DTG curves was 234.7oC for Fe3O4 and 358.1oC for MnFe2O4, respectively, indicating that the stability against oxidation of MnFe2O4 was improved.