Iron-iron oxide core-shell nanoparticles synthesized by laser pyrolysis followed by superficial oxidation

被引：59

作者：

Dumitrache, F

Morjan, I

Alexandrescu, R

Ciupina, V

Prodan, G

Voicu, I

Fleaca, C

Albu, L

Savoiu, M

Sandu, I

Popovici, E

Soare, I

机构：

[1] Natl Inst Lasers, Bucharest 077125, Romania

[2] Ovidius Univ Constanta, Constanta, Romania

来源：

APPLIED SURFACE SCIENCE | 2005年 / 247卷 / 1-4期

关键词：

laser pyrolysis; passivation; iron core-oxide shell nanocomposite; carbon nanotube;

D O I：

10.1016/j.apsusc.2005.01.037

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Iron-based core-shell nanostructures were synthesized by laser pyrolysis in a two-steps procedure. In a first step, using a cross-flow configuration, the laser radiation was heating a gas phase mixture containing iron pentacarbonyl (vapors) entrained by an ethylene flow, which plays also the role of an energy transfer agent. Secondly, a carefully controlled in situ passivation of the freshly formed pyrophoric iron nanoparticles created a protective iron oxide shell. The produced nanoparticles (22 nm size diameters) with core-shell features were analyzed by TEM, XRD, SAED and Raman spectroscopy. Majoritary iron and gamma iron oxide/magnetite and minoritary carbon phases were identified. In laser pyrolysis experiments in which the reaction temperature was increased, the catalyzed homogeneous nucleation and growth of carbon nanotubes in the gas phase was observed and is presented here for the first time. (c) 2005 Elsevier B.V. All rights reserved.

引用

页码：25 / 31

页数：7

共 19 条

[1] Preparation of iron carbide and iron nanoparticles by laser-induced gas phase pyrolysis [J].