Combustion synthesis of Ni–Zn ferrite powder—influence of oxygen balance value

In this study, Ni0.5Zn0.5Fe2O4 powder was synthesized via an exothermic reaction between nitrates [Ni(NO3)2·6H2O, Zn(NO3)2·6H2O, Fe(NO3)3·9H2O, and NH4NO3] and glycine [NH2CH2COOH]. By adjusting the glycine-to-nitrates ratio, the oxygen balance (OB) values of the reactant mixtures can be varied in which the combustion phenomena is altered and thereby the as-synthesized products with different characteristics are obtained. An interpretation based on the measurement of maximum combustion temperature (Tc) and the amounts of gas evolved during reaction for various OB values has been proposed regarding the nature of combustion and its correlation with the characteristics of as-synthesized products. After instrumental analyses, it is shown that the as-synthesized powders are nanoscale crystallites with a large specific surface area and they inherit a superparamagnetic behavior.