Morphological study of graphite-encapsulated iron composite nanoparticles fabricated by a one-step arc discharge method
Morphological study of graphite-encapsulated iron composite nanoparticles fabricated by a one-step arc discharge method
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DOI：
10.1016/j.apsusc.2017.04.231
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发表时间：
2017-09
影响因子：
6.7
通讯作者：
Rui Hu;Taiki Furukawa;Xiangke Wang;M. Nagatsu
中科院分区：
文献类型：
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作者：
Rui Hu;Taiki Furukawa;Xiangke Wang;M. Nagatsu
弧光放电是制备石墨包裹磁性纳米粒子的最有效方法之一。然而，考虑到超快的合成过程，了解在磁芯上量身定做贝壳的形态和质量一直是一个长期的挑战。为了更好地了解包覆层在等离子体中生长的机理，本研究对一系列合成参数进行了系统的研究。具体地说，(1)在背景气体中添加CH4浓度从0%到50%时，外壳的表面形貌演变得非常完整；(2)通过改变收集区靠近弧心，获得了更光滑的石墨化度更高的表面；(3)随着工作气体压力从100℃降低到25℃，外壳上的碳纳米环体积膨胀为连续的无定形覆盖物。并用XPS技术对其表面性质(Zeta电位和酸碱性质)进行了评价和解释。
Arc discharge is one of the most efficient approaches to fabricate graphite-encapsulated magnetic nanoparticles. However, given the ultra-fast synthetic procedure, the understanding of tailoring shell morphology and quality over magnetic core has been a long standing challenge. To better comprehend the mechanism of the encapsulating shell growth in plasma, a series of synthetic parameters were investigated systematically in this study. Specifically, (1) the surface morphology of the outmost shell evolved with high integrity by adding CH4concentration from 0% to 50% to He background gas; (2) a smooth surface with higher graphitization degree was achieved by changing collecting zone closer to the arc center; (3) carbon nano loops on the outmost shell expanded volumetrically to be continuous amorphous cover as the working gas pressure decreases from 100 to 25 Torr. The surface properties (i.e., zeta potential and acid-base character) were also evaluated and explained through XPS technique.