热处理温度对NiFe_2O_4纳米粉末红外特性及磁性能的影响  

Effects of Annealing Temperatures on the Infrared Spectrum Character and Magnetic Property of NiFe_2O_4 Nanoparticles

作　　者：孔小东[1,2] 郑家 

机构地区：[1]华中科技大学材料学院 [2]海军工程大学基础部,湖北武汉430033

出　　处：《磁性材料及器件》2003年第2期7-8,46,共3页Journal of Magnetic Materials and Devices

摘　　要：采用溶胶-凝胶法制备了NiFe2O4纳米粉末,并经不同温度处理。测定了样品的X射线衍射谱、红外漫反射光谱和磁性能。结果表明,200℃以上的热处理开始促进粉末的长大和晶化过程,而且随着温度的升高,晶化程度增强,粉末粒径增大。红外漫反射谱可以较好地反映粉末的尺寸效应和形态效应,粉末粒径越小,漫反射函数值越大;当粒径达到一定尺寸时,红外漫反射的尺寸效应和形态效应消失。NiFe2O4纳米粉末的磁性能与热处理温度及粉末的粒径大小有着十分密切的关系。NiFe2O4 nanoparticles were synthesized by sol-gel method, and were annealed at different temperatures. The structural, infrared character and magnetic properties were measured using X-ray diffractometer, diffuse reflectance spectroscopy and vibrating sample magnetometer. The results indicate that NiFe2O4 nanoparticles begin to grow and crystallize annealing at and above 200℃; the higher the annealing temperature is , the stronger the crystallization and the bigger the size of the particles are. And as the annealing temperature increases the K-M values of infrared diffuse reflection decreases and finally are independent to the size of particles and annealing temperature. The magnetic behavior of NiFe2O4 nanoparticle are related closely to the annealing temperature and the size of the nanoparticles.

关 键 词：NiFe2O4纳米粉末 红外漫反射谱 磁性 

分 类 号：TM277.1[一般工业技术—材料科学与工程]