The phase ZnFe2O4, franklinite, with spinel structure, has been synthesised
using solid-state reactions from the mechanically mixed powders of several
precursor salts. However, this method requires a high-temperature treatmen
t for some hours to homogenise the whole composition to obtain a single pha
se. In this paper ZnFe2O4 has been prepared by the ceramic method using dif
ferent precursors of Fe and Zn. The spinel has also been prepared by a citr
ate route that allows to prepare a homogeneous single phase at lower temper
ature and shorter annealing time. The citrate method has let to obtain sing
le phase of ZnFe2O4 at 600 degrees C/2h. In addition, this processing incre
ases the inversion grade with respect to the ceramic ones obtained with the
same precursor salts. The samples have been studied and characterised by m
eans of differential thermal analysis (DTA), thermal gravimetric analysis (
TGA), powder X-ray diffraction (XRD), Rietveld refinement method, Mossbauer
spectroscopy, scanning electron microscopy (SEM), energy dispersion of X-r
ay spectrometry (EDX) and magnetic measurements. The inversion grade has be
en detected by means of Rietveld analyses and corroborated by magnetic meas
urements. (C) 1999 Published by Elsevier Science Limited. All rights reserv
ed.