Department of Physics, Peking University, Beijing 100871, People's Republic of China.
J Phys Condens Matter. 2010 Mar 31;22(12):126003. doi: 10.1088/0953-8984/22/12/126003. Epub 2010 Mar 8.
Three powder samples of Ni nanochains formed of polycrystalline Ni nanoparticles with an estimated diameter of about 30 nm have been synthesized by a wet chemical method using different organic surfactants. These samples, having magnetically/structurally core-shell structures, all with a ferromagnetic Ni core, are Ni@Ni(3)C nanochains, Ni@Ni(SG) nanochains with a spin glass (SG) surface layer, and Ni@Ni(NM) nanochains with a nonmagnetic (NM) surface layer. The average thickness of the shell for these three samples is determined as about 2 nm. Magnetic properties tailored by the different surface magnetism are studied. In particular, suppression in the saturation magnetization, usually observed with magnetic nanoparticles, is revealed to arise from the surface magnetic states with the present samples.
已经通过湿化学方法使用不同的有机表面活性剂合成了三种由估计直径约为 30nm 的多晶 Ni 纳米颗粒组成的 Ni 纳米链粉末样品。这些具有磁/结构核壳结构的样品均具有铁磁 Ni 核，分别是 Ni@Ni(3)C 纳米链、具有自旋玻璃（SG）表面层的 Ni@Ni(SG)纳米链和具有非磁性（NM）表面层的 Ni@Ni(NM)纳米链。这三种样品的壳层平均厚度确定为约 2nm。研究了通过不同表面磁性定制的磁性特性。特别地，本样品中表面磁性状态导致通常在磁性纳米颗粒中观察到的饱和磁化强度的抑制。
