One-step synthesis of core(Cr)/shell(gamma-Fe(2)O(3)) nanoparticles

Jriuan Lai; Kurikka V P M Shafi; Abraham Ulman; Katja Loos; Ronit Popovitz-Biro; Yongjae Lee; Thomas Vogt; Claude Estournès

doi:10.1021/ja0443225

One-step synthesis of core(Cr)/shell(gamma-Fe(2)O(3)) nanoparticles

J Am Chem Soc. 2005 Apr 27;127(16):5730-1. doi: 10.1021/ja0443225.

Authors

Jriuan Lai¹, Kurikka V P M Shafi, Abraham Ulman, Katja Loos, Ronit Popovitz-Biro, Yongjae Lee, Thomas Vogt, Claude Estournès

Affiliation

¹ Othmer Department of Chemical and Biological Sciences and Engineering, Polytechnic University, 6 Metrotech Center Brooklyn, New York 11201, USA.

PMID: 15839638
DOI: 10.1021/ja0443225

Abstract

Core(Cr)/shell(gamma-Fe(2)O(3)) nanoparticles were synthesized by mixing Fe(CO)(5) and Cr(CO)(6) in the 9:1 ratio. These particles exhibit narrow size distribution with 13.5 nm as mean diameter and uniform spherical shape. The TEM image, which is in good agreement with the synchrotron powder XRD pattern, reveals the heterogeneous nature (core/shell structure). The analysis of the pattern reveals gamma-Fe(2)O(3) structure and a metal crystal structure. Mossbauer spectra, which support the superparamagnetic behavior determined by H-M measurement, do not show any traceable amount of Fe(0). This suggests that the metal component is Cr. EELS analysis and iron mapping suggest controlled stoichiometry and also confirm a core made of Cr and a shell made of gamma-Fe(2)O(3).