自燃烧法制备CoFe_2O_4纳米颗粒及其磁性研究

用柠檬酸自燃烧法制备出CoFe_2O_4纳米粉末,对燃烧产物在不同温度下热处理,用扫描电镜(SEM),x射线光电子能谱(XPS),红外吸收谱(IR)对燃烧产物进行形貌,成分以及化学键分析,用x射线衍射(XRD)对燃烧产物及热处理产物进行晶体结构分析,结果显示燃烧产物为CoFe_2O_4纯相,尺寸在40～80nm之间,且有较高的分散性和低的团聚。用振动样品测磁计(VSM)在室温下测量了燃烧产物及热处理产物的磁滞回线,发现测得的比饱和磁化强度(Ms),矫顽力(Hc)以及剩磁比(Mr/Ms)均强烈依赖于热处理温度,Ms随热处理温度升高而增大,而样品的Hc与Mr/Ms均当热处理温度为400℃时达到最大,并且Hc达到了3180Oe。

Synthesis and Magnetic Propertise of CoFe2O4 Nanoparticles by Auto-Combustion Method

CoFe_2O_4 nanopartieles were prepared by citric acid auto-combustion method,the as-burnt powders were calcined at different temperature,the morphology,component,and chemical bond were respectively studied by Scanning E- lectron Microscopy(SEM),x-ray Photoolectron Spectroscopy(XPS),and Infrared spectroscopy(IR),the crystal struc- ture of the as-burnt powders and products calcined at different temperature was characterized by X-Ray Diffraction(XRD), the results shows that the as-burnt powders were pure CoFe_2O_4 phase with high dispersibility and relatively low agglomera- tion,and the particle size is between 40 and 80nm,The magnetic hysteresis loops of the as-burnt powders and products cal- cined at different temperature were collected at room temperature(RT)using a vibrating sample magnetometer(VSM), the results shows that saturation magnetization(Ms),coercivity(He) and remanence ratio(Mr/Ms)were drastically de- pending upon the annealing temperature,Ms increased with increasing temperature,while Hc and Mr/Ms both reached maximum values as the as-burnt powders were calcined at 400℃,and Hc reached 3180Oe.