Crystalline silicon (Si) nanoparticles (NPs) doped with iron (Fe) in the range from 0.02 to 2.5 at.% were prepared by plasma-ablative synthesis and were investigated by means of the transmission electron microscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), infrared spectroscopy and nuclear magnetic resonance relaxometry. While the nanocrystal size in Si:Fe NPs did not depend significantly on Fe content, the hydrodynamic diameter of NPs in aqueous suspensions increases from 50 to 180[Formula: see text]nm. Both the transverse and longitudinal proton relaxation time were found to decrease in the prepared suspensions of Si:Fe NPs. Maximal shortening of the transverse relaxion was observed for Si:Fe NPs with 0.2 at.% of Fe and the relaxation rate was almost linearly proportional to the NP concentration. Both these findings and in vivo tests indicate that Si:Fe NPs are promising for biomedical applications in magnetic resonance imaging (MRI) and therapy of cancer.

中文翻译：

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用于多功能应用的含铁杂质的硅纳米粒子

通过等离子体烧蚀合成制备了掺杂有 0.02 至 2.5 at.% 的铁 (Fe) 的结晶硅 (Si) 纳米粒子 (NPs)，并通过透射电子显微镜、X 射线衍射 (XRD) 进行了研究。 、动态光散射 (DLS)、红外光谱和核磁共振弛豫测量。虽然 Si:Fe NPs 中的纳米晶体尺寸不显着取决于 Fe 含量，但水悬浮液中 NPs 的流体动力学直径从 50 增加到 180[公式：见文本]nm。在制备的 Si:Fe NPs 悬浮液中，发现横向和纵向质子弛豫时间都减少了。对于具有 0.2 at.% Fe 的 Si:Fe NPs，观察到横向弛豫的最大缩短，弛豫率几乎与 NP 浓度成线性比例。