纳米镍/炭复合材料的制备与磁性表征

以废弱酸型聚丙烯酸系阳离子交换树脂为炭前驱体,经过与镍离子交换后,再经热解制备纳米镍粒子均匀分散于炭基体的纳米镍/炭(Ni/C)复合材料.以XRD、TEM为主要分析手段研究了热解条件对纳米镍粒子在Ni/C复合材料中的形貌、大小的影响.结果表明:通过热解条件可以控制Ni/C复合材料中纳米镍粒子的平均粒径;热解温度的升高和热解保温时间的增加都可使Ni/C中纳米镍粒径增大.磁性能测试结果表明: Ni/C-500表现为超顺磁特性,而Ni/C-600、Ni/C-700为铁磁性;Ni/C-600、Ni/C-700的比剩磁化强度、矫顽力都要大于微米镍粉与块体镍,但其比饱和磁化强度要小于微米镍粉和块体镍.

Preparation and magnetic behavior of nano-Ni/C composite material

A kind of Ni/C composite material,in which nano nickle particles were uniformly distributed in carbon matrix,was prepared by pyrolysis of Ni-exchanged cation exchange resin(Ni-PAA).The effect of pyrolytic conditions on the morphology,size of nano nickel particles in Ni/C composite material was studied by means of X-ray diffraction(XRD),Transmission Electron Microscope(TEM).The results show the particle size of nano nickel in Ni/C can be controlled by pyrolytic conditions;the particle size increases as the pyrolytic temperature and the holding time increase.Magnetic tests show that Ni/C-500 is superparamagnetic,while Ni/C-600,Ni/C-700 are ferromagnetic.The remanence and the coercivity at room temperature of Ni/C-600 and Ni/C-700 are higher than those of the corresponding micrometer nickel powders and bulk nickle,while the saturation magnetization is lower than those of micrometer nickel powders and bulk nickel.