Abstract The saturation magnetization of composites of carbon nanotubes and CoFe2O4 (CFO) magnetic nanoparticles synthesized through a novel one-step process in the presence of a surfactant (sodium dodecyl-benzene-sulfonate) show significant increase, to 208 emu/g. This value of saturation magnetization of the composite is a factor of 3.3 higher than pristine CFO nanoparticles. This is the first time such a remarkable magnetic behavior of CFO/ carbon nanotubes composite is presented. The increased magnetism is attributed to the proximity effect between uniformly distributed ferromagnetic CFO nanoparticles on the surface of carbon nanotubes and hybridization of the π -electronic states of carbon and the 3d-bands of CFO. Scanning electron microscopy images confirm uniform and dense distribution of CFO nanoparticles on carbon nanotubes. Magnetic force microscopy images confirm the formation of uniformly distributed magnetic stripe domains. The sample was characterized at ambient using X-ray diffraction, Raman Spectroscopy, atomic force microscopy, scanning electron microscopy, scanning transmission electron microscopy, and high-resolution transmission electron microscopy. Magnetic properties were characterized by magnetic force microscopy and magnetometry using vibrating sample magnetometer.

中文翻译：

---

碳纳米管和 CoFe2O4 纳米粒子复合材料中的邻近效应调节磁性能

摘要 在表面活性剂（十二烷基苯磺酸钠）存在下，通过新型一步法合成的碳纳米管和 CoFe2O4 (CFO) 磁性纳米粒子复合材料的饱和磁化强度显着增加，达到 208 emu/g。该复合材料的饱和磁化强度值比原始 CFO 纳米粒子高 3.3 倍。这是第一次展示 CFO/碳纳米管复合材料的如此显着的磁性行为。增加的磁性归因于碳纳米管表面上均匀分布的铁磁 CFO 纳米粒子之间的邻近效应以及碳的 π 电子态和 CFO 的 3d 带的杂化。扫描电子显微镜图像证实了碳纳米管上 CFO 纳米粒子的均匀和密集分布。磁力显微镜图像证实了均匀分布的磁条畴的形成。使用 X 射线衍射、拉曼光谱、原子力显微镜、扫描电子显微镜、扫描透射电子显微镜和高分辨率透射电子显微镜在环境下表征样品。通过磁力显微镜和使用振动样品磁强计的磁力计来表征磁特性。