The invention discloses a low-temperature preparation method of Co ferrite Nano
powder. Co(CH3CO2)2.4H2O, Fe(NO3)3.9H2O and poly-hydroxyl
carboxylic acid are used as raw materials, and analytically pure
ethylene glycol methyl
ether and water are mixed to be used as a
solvent, wherein the volume ratio of the analytically pure
ethylene glycol methyl
ether to water is (7-9):1. The preparation method comprises the following steps of: firstly, dissolving Co(CH3CO2)2.4H2O and Fe(NO3)3.9H2O in the mixed
solvent; secondly, adding poly-hydroxyl
carboxylic acid to the solution, slowly dropping analytically pure
ammonia water to the solution under a stirring condition, adjusting the pH value to approximate 6, and slowly evaporating the solution to form the brown
sol in a water bath at 70 DEG C; thirdly, heating the
sol to 130 DEG C or refluxing for 12h till the
sol forms the brownish black xerogel, transferring the xerogel to an oven at 250 DEG C, wherein the xerogel can combust automatically to produce the dendritic and bulking products, and
grinding the products to obtain the Co ferrite Nano
powder. The low-temperature preparation method of the Co ferrite Nano
powder has simple process, low cost, easily controllable chemical constituent, good repetition and easy
doping; and the particle of the prepared product has good dispersibility,
uniform size and good magnetic properties.