High-efficiency plasma surface modification of graphite-encapsulated magnetic nanoparticles using a pulsed particle explosion technique
High-efficiency plasma surface modification of graphite-encapsulated magnetic nanoparticles using a pulsed particle explosion technique
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DOI：
10.7567/jjap.53.010205
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发表时间：
2013
影响因子：
1.5
通讯作者：
T. Saraswati;Shun Tsumura;M. Nagatsu
中科院分区：
文献类型：
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作者：
T. Saraswati;Shun Tsumura;M. Nagatsu
研究了一种利用电感耦合射频等离子体结合脉冲粒子爆炸技术对石墨包覆铁化合物磁性纳米粒子进行高效表面改性的方法。通过在氨等离子体中以1 kHz的重复频率和50%的占空比向衬底台施加-1kV的负脉冲偏压15秒或更短时间，获得了X射线光电子能谱中的N1s峰强度的显著增加。在脉冲粒子爆炸系统中处理的纳米粒子的N1s峰的强度和N/C比无偏压处理的粒子高3-4倍。使用本技术处理的纳米颗粒的氨基群体被确定为每个纳米颗粒约8.2 × 104个分子，比无偏差处理的颗粒高大约4倍。等离子体处理的纳米粒子的分散性显着改善相比，未经处理和处理的粒子在非偏压系统。通过透射电子显微镜对表面结构的分析表明，处理后的纳米粒子的结构或形貌没有明显的损伤，表明本技术适用于高效的磁性纳米粒子的表面改性。
A high-efficiency surface modification of graphite-encapsulated iron compounds magnetic nanoparticles using an inductively coupled radio-frequency plasma with a pulsed particle explosion technique was studied. A significant increase in N 1s peak intensity in the X-ray photoelectron spectroscopy spectra was obtained by applying a negative pulsed bias voltage of −1 kV to the substrate stage for 15 s or less at a repetition frequency of 1 kHz and a duty ratio of 50% in ammonia plasma. The intensity of the N 1s peak and the N/C ratio of the nanoparticles treated in a pulsed particle explosion system were 3–4 times higher than those of the particles treated without bias. The amino group population of nanoparticles treated using the present technique was determined to be about 8.2 × 104 molecules per nanoparticle, roughly four times higher than that of particles treated without bias. The dispersion of the plasma-treated nanoparticles was significantly improved compared with those of the untreated and treated particles in the nonbiasing system. The surface structure analysis by transmission electron microscopy showed no significant damage on the structure or morphology of the treated nanoparticles, indicating that the present technique is applicable to the high-efficiency surface modification of magnetic nanoparticles.