摘要
在无稀土永磁的备选材料中,钴铁氧体由于其显著的优势,如储量高成本低,化学性能稳定,绿色环保等特点而备受关注。因此虽然其磁性不是很高,但其磁性的调节增强是近年来重要的研究方向之一。采用设备操作都很简单的化学共沉淀法,制备了不同含量铈离子(Ce^(3+))掺杂的钴铁氧体纳米材料CoFe_(2-x)Ce_(x)O_(4)(x=0,0.05,0.10,0.15;摩尔分数),并研究了铈离子含量对钴铁氧体结构和磁性的影响。X射线衍射(XRD)结果表明掺杂前后钴铁氧体均是立方尖晶石结构,其晶格参数和晶粒尺寸随x的增加先增大后减小,并在x≥0.10的样品中出现明显的氧化铈衍射峰;X射线光电子能谱(XPS)结果进一步验证氧化铈的存在。磁性测量结果表明,钴铁氧体的饱和磁化强度(Ms)随x的增加先增加而后稍微减小,而矫顽力(Hc)则是出现先降低后增加而后再降低的震荡变化;分析后发现造成这种变化的原因是钴铁氧体的磁性变化受Ce^(3+)的掺杂和晶粒尺寸的双重影响造成的。Ce^(3+)掺杂取代Fe^(3+)会使Ms降低而Hc增大,而晶粒尺寸对磁性的影响正好相反。对最大磁能积((BH)_(max))进行分析发现掺杂Ce^(3+)后(BH)_(max)都有所增加。x=0.10的样品由于Ms和Hc都相对较大,因此(BH)_(max)达到最大,为4.38 kJ·m^(3);而此掺杂量的样品中有少量氧化铈出现,说明Ce^(3+)掺杂时钴铁氧体中少量氧化铈的存在对磁性的负面影响可忽略不计。
In modern technologies,rare earth permanent magnetic materials with high coercivity and magnetic energy product are becoming increasingly important because of their great application in many emerging industries,such as electro-motors,wind generators,and so on.While the rare earth materials are non-renewable resources,the long-term availability and price stability could not be guaranteed.So,the development of new rare-earth-free hard magnetic materials is of paramount importance in materials science.For this purpose,various substitute magnetic materials without rare earth element while have great potential using for hard magnetism have been studied,such as MnGa,MnBi,FePt,CoPt,and so on.Among the various alternative substitute materials,cobalt ferrite attracts much attention for its significant advantages,such as the high reserves,low cost,stable chemical performance,and green environmental protection,and so on.Although its magnetic properties are not very high,the enhancement of its magnetic properties is one of the important research directions in recent years.There have been many reports that rare earth element doping can effectively improve the magnetic properties of cobalt ferrite,such as neodymium,terbium,gadolinium,and so on.Here,the light rare earth cerium element was selected,which has high reserves but low price,as the dopant and studied the change of the magnetism of the cobalt ferrite after doping.Using chemical coprecipitation method rare earth Ce^(3+)doped cobalt ferrites of nominal composition CoFe_(2-x)Ce_(x )O_(4 )(x=0,0.05,0.10,0.15) nanoparticles were prepared,and the effect of Ce^(3+)doping on structural,morphological and magnetic properties was analyzed using X-ray diffraction (XRD),Fourier transform infrared spectroscopy (FTIR),field emission scanning election microscopy (FESEM) and vibrating sample magnetometer (VSM).The results showed that the structural property was related to Ce^(3+)contents directly and the magnetic properties of the cobalt ferrite after Ce^(3+)doping were improved.XRD re
作者
秦秀芳
赵睿
张婷
马源莉
Qin xiufang;Zhao Rui;Zhang Ting;Ma Yuanli(Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education,Research Institute of Materials Science,School of Chemistry and Materials Science,Shanxi Normal University,Linfen 041004,China)
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2023年第10期1380-1388,共9页
Chinese Journal of Rare Metals
基金
国家自然科学基金青年基金项目(51701106)资助。
关键词
钴铁氧体
磁性
最大磁能积
稀土元素
掺杂
cobalt ferrite
magnetic properties
maximum energy product
rare earth
doping
