Abstract This paper reports on the preparation of nanocomposites containing mesoporous carbon with different molar ratios of Ni or CoFe2O4 nanoparticles as magnetically separable absorbents by facile, reproducible and economical processes including self-assembly soft template hydrothermal route and Pechini-type sol-gel techniques. Accordingly, structural, morphological and magnetic properties of the samples were studied using XRD, FT-IR, FE-SEM, HR-TEM, N2 adsorption-desorption and VSM methods. Based on the VSM results, two different types of magnetic behavior were observed. Composites containing nickel had typical S-shaped hysteresis curves with a very low coercivity (Hc ≈ 84, 97 Oe) and retentivity (Mr ≈ 1.1, 2.4 emu/g), as compared to their relatively high saturation magnetization value (Ms ≈ 3.9, 8.6 emu/g), while the other samples were ferromagnetic. The M − H curves have also revealed that saturation and remnant magnetization, as well as coercivity, were increased by enhancing the magnetic phase content in all nanocomposites. Also, the MC-Ni/CFO nanocomposites performance as the magnetically separable adsorbents for vitamin B12 adsorption was evaluated. The MC-5CFO adsorbent illustrated higher adsorption capacity (325.66 mg/g) than MC-2Ni (139.25 mg/g) in 250 ppm due to the higher BET surface area (589 m2/g) and pore volume (0.71 cm3/g).

中文翻译：

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磁性可分离介孔碳的结构、形态和磁性研究

摘要 本文报道了通过包括自组装软模板水热路线和 Pechini 型溶胶-凝胶技术在内的简便、可重复和经济的方法制备含有具有不同摩尔比的 Ni 或 CoFe2O4 纳米颗粒的介孔碳的纳米复合材料作为可磁分离的吸收剂。因此，使用 XRD、FT-IR、FE-SEM、HR-TEM、N2 吸附-解吸和 VSM 方法研究了样品的结构、形态和磁性。根据 VSM 结果，观察到两种不同类型的磁行为。含有镍的复合材料具有典型的 S 形磁滞曲线，具有非常低的矫顽力 (Hc ≈ 84, 97 Oe) 和保持性 (Mr ≈ 1.1, 2.4 emu/g)，与其相对较高的饱和磁化强度值 (Ms ≈ 3.9, 8.6 鸸鹋/克), 而其他样品是铁磁性的。M - H 曲线还表明，通过提高所有纳米复合材料中的磁相含量，饱和度和剩余磁化强度以及矫顽力都增加了。此外，还评估了 MC-Ni/CFO 纳米复合材料作为维生素 B12 吸附的磁分离吸附剂的性能。由于更高的 BET 表面积 (589 m2/g) 和孔体积 (0.71 cm3/g)，MC-5CFO 吸附剂在 250 ppm 时表现出比 MC-2Ni (139.25 mg/g) 更高的吸附容量 (325.66 mg/g) .