在密闭容器中,用爆轰分解掺杂含有镍离子的混合炸药前驱体合成了核壳结构石墨包覆镍纳米颗粒。调整混合炸药前驱体中碳源材料和金属源材料的有效摩尔比合成了球形、不同尺寸、核壳结构的磁性石墨包覆纳米镍颗粒。采用X射线衍射仪(XRD)、透射电镜(TEM)、能谱分析仪(EDX)和振动样品磁强计(VSM)表征化学构成、结构形貌及磁性能。结果表明:颗粒大小主要分布在10~55 nm之间,复合纳米颗粒主要由面心立方镍纳米晶体和石墨碳构成,常温下这些复合纳米颗粒主要表现出超顺磁性和铁磁性能。
Aimed at synthesizing the encapsulation of nickel nanocrystal within graphitic carbon,effective experiments were carried out by adjusting the mole ratio of carbon source and metal source in these precursors.The chemical composition,nanostructures and magnetic properties of the composite particles were analyzed by using X-ray diffraction(XRD),transmission electron microscopy(TEM),energy dispersive X-ray detector(EDX) and vibrating sample magnetometer(VSM).The results showed that the different size and spherical graphite-encapsulated nickel nanoparticles with a perfect core-shell structure had been prepared and that these magnetic composite particles mainly distributed in 10-55 nm.The magnetic measurements demonstrated that the as-prepared CENNPs took on superparamagnetic or ferromagnetic behaviors at room temperature.