Some magnetic properties of γ-Fe2O3 synthesized from ferrous fumarate half-hydrate
Abstractγ-Fe2O3 synthesized from ferrous fumarate half-hydrate was studied by measurements of D.c. electrical conductivity, Seebeck coefficient, initial magnetization and magnetic hysteresis, and by Mössbauer spectroscopy and scanning electron microscopy. The phase transformation observed by electrical conductivity measurements matched well with the phase transformation observed by the variation with temperature of initial magnetization measurements of γ-Fe2O3; this magnetic study also established the single-domain character of γ-Fe2O3. The magnetic hysteresis values of the γ-Fe2O3 synthesized indicated improved values over that of a γ-Fe2O3 sample synthesized by established procedures. The scanning electron micrographs showed that the γ-Fe2O3 particles were acicular in shape and the Mössbauer spectrum showed a well-resolved six-band spectrum. The presence of a hydrogen ferrite phase was also confirmed by the electrical and magnetic measurements.