双晶赤铁矿纳米线。

Bicrystalline hematite nanowires.

作者信息

Wang Rongming, Chen Yaofeng, Fu Yunyi, Zhang Han, Kisielowski Christian

机构信息

State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People's Republic of China.

出版信息

J Phys Chem B. 2005 Jun 30;109(25):12245-9. doi: 10.1021/jp051197q.

DOI:10.1021/jp051197q

PMID:16852510

Abstract

Bicrystalline nanowires of hematite (alpha-Fe(2)O(3)) have been successfully synthesized by the oxidation of pure iron. The product was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM in combination with focal series reconstruction, energy-dispersive X-ray spectroscopy, and electron energy-loss spectroscopy. The bicrystalline nanowires have diameters of 20-80 nm and lengths up to 20 microm. All of the investigated materials are found to be alpha-Fe(2)O(3) with a rhombohedral crystal structure. Investigations indicate that most of the bicrystalline nanowires are nanotwins with ellipsoidal heads. The orientation relationship between the nanotwins can be described as (110)(M)//(110)(T), 110//0. An energy-filtered TEM investigation indicates that the ellipsoidal head is iron-rich. The growth mechanism of such unique nanostructures is considered to be a solid-phase growth via surface and internal diffusions of molecules from base to tip.

摘要

通过纯铁的氧化反应成功合成了赤铁矿（α-Fe₂O₃）双晶纳米线。采用X射线衍射、扫描电子显微镜、透射电子显微镜（TEM）、结合聚焦系列重建的高分辨率TEM、能量色散X射线光谱和电子能量损失光谱对产物进行了表征。双晶纳米线的直径为20-80nm，长度可达20μm。所有研究材料均为具有菱面体晶体结构的α-Fe₂O₃。研究表明，大多数双晶纳米线是具有椭圆形头部的纳米孪晶。纳米孪晶之间的取向关系可描述为(110)(M)//(110)(T)，110//0。能量过滤TEM研究表明，椭圆形头部富含铁。这种独特纳米结构的生长机制被认为是通过分子从底部到尖端的表面和内部扩散进行的固相生长。