Izydorzak-Wozniak M, Leonowicz M
J Nanosci Nanotechnol. 2014 Mar;14(3):2258-67. doi: 10.1166/jnn.2014.8516.
It was found that by varying the pyrolysis temperature of the polymeric precursor, carbon matrix magnetic nanocomposites with different constitution and fractions of magnetic component were made. X-ray diffraction, transmission electron microscopy and Raman spectroscopy revealed the presence of nanocrystallites (NCs) of Co, Fe3C and Ni embedded in porous, partially-graphitized carbon matrix. Vibrating sample magnetometer measurements enabled to determine the correlation between NCs size distribution and magnetic properties. The magnetic studies confirmed that the coercivity, saturation and remanent magnetizations, as well as fraction of the magnetic component depend on the pyrolysis temperature. The Co#C and Fe3C#C composites exhibited ferromagnetic behavior with a remanent to saturation magnetization (M(R)/M(S)) ratio ranging from 0.25 to 0.3, whereas in the Ni containing samples a relatively small M(R)/M(S) ratio point to significant contribution of superparamagnetic interactions. As the carbon matrix magnetic nanocomposites are proposed for biomedical application the basic cytotoxicity test were performed to evaluate a potential toxic effect of the materials on MG-63 cells line.
研究发现，通过改变聚合物前驱体的热解温度，可以制备出具有不同磁性组分组成和比例的碳基磁性纳米复合材料。X射线衍射、透射电子显微镜和拉曼光谱表明，在多孔、部分石墨化的碳基体中存在嵌入的Co、Fe3C和Ni纳米微晶（NCs）。振动样品磁强计测量能够确定NCs尺寸分布与磁性之间的相关性。磁性研究证实，矫顽力、饱和磁化强度和剩余磁化强度以及磁性组分的比例取决于热解温度。Co#C和Fe3C#C复合材料表现出铁磁行为，剩余磁化强度与饱和磁化强度之比（M(R)/M(S)）在0.25至0.3之间，而在含Ni样品中，相对较小的M(R)/M(S)比值表明超顺磁相互作用的贡献显著。由于碳基磁性纳米复合材料被提议用于生物医学应用，因此进行了基本的细胞毒性测试，以评估该材料对MG-63细胞系的潜在毒性作用。
