Premium
Elaboration of superparamagnetic cobalt–ferrite nanocomposites from films of chitosan chelates
Author(s) -
GarzaNavarro M. A.,
GonzálezGonzález V. A.,
TorresCastro A.,
Hinojosa M.,
GarcíaLoera A.,
JoséYacamán M.
Publication year - 2010
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.31043
Subject(s) - superparamagnetism , materials science , coprecipitation , nanocomposite , cobalt , ferrite (magnet) , magnetization , spinel , transmission electron microscopy , chemical engineering , nanoparticle , composite material , nanotechnology , magnetic field , metallurgy , physics , quantum mechanics , engineering
Cobalt–ferrite nanocomposites were synthesized from polymeric films of chelates of Co(II) and Fe(III) ions within a chitosan matrix by a solid‐state coprecipitation reaction with weight content ratios of chitosan to cobalt–ferrite of 50/50 and 25/75 w/w. Morphological and crystalline studies of the composites were performed by high‐resolution transmission electron microscopy, X‐ray diffraction, and selected area electron diffraction with a nanobeam diffraction probe. The results show nanoparticles around 4 nm with a spinel structure, consistent with the cobalt–ferrite phase. The magnetic behavior was evaluated with curves of the applied‐field‐dependent magnetization [ M ( H )] and the temperature‐dependent magnetization [ M ( T )]. Both the M ( H ) and M ( T ) curves showed typical superparamagnetic behavior, depicting an absence of hysteretic characteristics and the characteristic peak at blocking temperature in the zero‐field‐cooled curve. There was also evidence of strong interparticle and intraparticle interactions, which suggested magnetic frustration in the particle magnetic moment alignment with the applied field. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010