CoZ-Ferrite Fine Powder Prepared by Gel-Combustion

抄録

Gel-combustion synthesis was applied for CoZ-ferrite (Ba3Co2Fe24O41) fine powder. Either citric acid or glycine was added to the mixed aqueous solution of Ba(NO3)2, Co(NO3)2•6H2O and Fe(acac)3. The product gel was ignited at 150^oC and then fired again up to a temperature of 500^oC to 1200^oC. The ignited and fired products were respectively a mixture of CoFe2O4 and Ba(NO3)2 and that of CoZ-, CoY-, M-ferrites and BaFe2O4 when citric acid was used as a gelling agent. The ignited product was a mixture of CoFe2O4 and BaFe2O4 because higher temperature was attained in the ignition of glycine gel than citric acid gel. CoZ-ferrite fine powder was obtained in firing the ignited product at 1000^oC. Crystallite and average particle sizes were 45 and 200nm, respectively. Saturation magnetization was 250G and coercivity was 0.6 to 0.9kOe.