The thermal analysis of strontium and barium hexa(formato)ferrates(III), M3[Fe(HCOO)6]2. xH2O, has been carried out from ambient temperature to 800 °C. Various physico-chemical techniques, i.e., TG, DTG, DSC, XRD,
IR, Mössbauer spectroscopy, etc., have been employed to characterize the intermediates/end products. After dehydration, the
anhydrous complexes undergo decomposition to yielda-Fe2O3and metal oxalate in the temperature range of 275-290 °C. A subsequent oxidative decomposition of metal oxalate leads to the
formation of respective alkaline earth metal carbonate in successive stages. Finally, nanosized ferrites of Sr2Fe2O5and BaFe2O4stoichiometry have been obtained as a result of a solid-state reaction betweena-Fe2O3and a fraction of MCO3. The temperature of ferrite formation is much lower than possible in the conventional ceramic method.