A Study of γ-Fe₂O₃ Nanoparticles Modified Using ZnCl₂ during Synthesis

Longlong Chen, Jian Li

School of Physical Science & Technology, Southwest University, Chongqing, China.

DOI: 10.4236/ampc.2013.31A004                

Abstract

Surface modification of γ-Fe₂O₃ nanoparticles synthesized by a chemically induced transition has been attempted by adding ZnCl₂ during synthesis. The structure of the modified particles was studied using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The experimental results showed that ZnFe₂O₄ grew epitaxially on the γ- Fe₂O₃ crystallites to form composite nanoparticles with the spinel structure, on which FeCl₃ might be adsorbed. The apparent grain size d_c estimated by XRD using the Scherrer equation was larger rather than smaller than the average particle size measured by TEM. This paradox can be explained by the effect of absorption in the coating heterolayer.

Keywords

Composite Nanoparticle; Spinel Structure; X-Ray Diffraction; Scherrer Equation

Conflicts of Interest

The authors declare no conflicts of interest.

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