Magnetic Properties for the Single-domain Co Fe_2O_4 Nanoparticles Synthesized by the Hydrothermal Method  

作　　者：杨芝 ZHANG Yue SONG Yu WANG Jiawei CHEN Yuang ZHANG Zhe DUAN Nian 阮学峰 

机构地区：[1]City College, Wuhan University of Science and Technology [2]School of Optical and Electronic Information,Huazhong University of Science and Technology [3]Center of Nanoscience and Nanotechnology and School of Physics and Technology, Wuhan University

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2015年第6期1140-1146,共7页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Natural Science Foundation of China(51172166);the PhD Programs Foundation of City College,Wuhan University of Science and Technology(2014CYBSKY003)

摘　　要：The aim of this work was to investigate the size-related magnetism for the single-domain Co Fe2O4 nano-particles synthesized using the hydrothermal method. The effects of the reaction temperature and the reaction time on the lattice constants, particle morphologies, and the room-temperature magnetic properties were studied from the X-ray diffraction, the transmission electron microscope, and the vibrating-sample magnetometer. The experimental results show that the samples are composed of Co Fe2O4 nano-particles with an average crystallite size（D） smaller than 40 nm, and the magnetic properties of the samples can be manipulated in a wide range： the MS values vary from smaller than 50 emu/g to close to 80 emu/g, and the HC values are between about 200 Oe and 2000 Oe. Additionally, the relationship between HC and 1/D^3/2 satisfi es linearship, showing the characteristic of single-domain structure. These results indicate that the single-domain Co Fe2O4 nano-particles with size controlled between the superparamagnetic critical size and single-domain critical size can be easily prepared using this hydrothermal method.The aim of this work was to investigate the size-related magnetism for the single-domain Co Fe2O4 nano-particles synthesized using the hydrothermal method. The effects of the reaction temperature and the reaction time on the lattice constants, particle morphologies, and the room-temperature magnetic properties were studied from the X-ray diffraction, the transmission electron microscope, and the vibrating-sample magnetometer. The experimental results show that the samples are composed of Co Fe2O4 nano-particles with an average crystallite size（D） smaller than 40 nm, and the magnetic properties of the samples can be manipulated in a wide range： the MS values vary from smaller than 50 emu/g to close to 80 emu/g, and the HC values are between about 200 Oe and 2000 Oe. Additionally, the relationship between HC and 1/D^3/2 satisfi es linearship, showing the characteristic of single-domain structure. These results indicate that the single-domain Co Fe2O4 nano-particles with size controlled between the superparamagnetic critical size and single-domain critical size can be easily prepared using this hydrothermal method.

关 键 词：hydrothermal CoFe2O4 single-domain nano-particles magnetic properties 

分 类 号：TB383.1[一般工业技术—材料科学与工程] O614.812[理学—无机化学]