Chemically ordered decahedral FePt nanocrystals observed by electron microscopy
Chemically ordered decahedral FePt nanocrystals observed by electron microscopy
复制标题
DOI：
10.1103/physrevb.89.161406
复制
发表时间：
2014-04-24
影响因子：
3.7
通讯作者：
Farle, M.
中科院分区：
文献类型：
--
作者：
Li, Zi-An;Spasova, M.;Farle, M.
采用高分辨率透射电子显微镜（HRTEM）和扫描透射电子显微镜（STEM）高角度环形暗场（HAADF）成像技术，对气相缩合法制备的平均尺寸为6 nm的FePt纳米颗粒的晶体结构进行了表征。这些FePt纳米颗粒被发现是化学有序的，十面体形状的，并且在表面富集Pt。将实验测定的Fe和Pt原子的晶格常数和分布与有序十面体FePt纳米粒子的第一性原理计算结果进行了比较，证实了具有Fe/Pt有序和Pt表面偏析的独特十面体结构的发现。
The crystal structure of FePt nanoparticles of mean size of 6 nm produced by gas-phase condensation is characterized using a combination of high-resolution transmission electron microscopy (HRTEM) and high-angle annular dark field (HAADF) imaging in scanning transmission electron microscopy (STEM). These FePt nanoparticles are found to be chemically ordered, decahedral shaped, and Pt enriched at the surfaces. The experimentally determined crystallographic lattice constants and distribution of Fe and Pt atoms are compared with first-principles calculations of ordered decahedral FePt nanoparticles to confirm the discovery of a unique decahedral structure with Fe/Pt ordering and Pt surface segregation.