Synthesis of NiFe_2O_4 Spinel Nanopowder via Low-Temperature Solid-State Reactions

NiFe2O4 spinel nanopowder was synthesized by low-temperature solid-state reactions where NaCl was taken as dispersant and FeSO4·7H2O,NiSO4·6H2O and NaOH as starting materials.The precursors prepared by grinding the dispersant and reacting substances sufficiently at room temperature were calcined to obtain NiFe2O4 spinel nanopowder.The effects of NaCl content,calcining temperature and holding time on the particle size and powder morphology were investigated emphatically using X-ray diffraction(XRD)and scanning electron microscopy(SEM)to characterize the as-prepared product.The results showed that the NiFe2O4 spinel nanopowder prepared by calcining the precursor with 20wt% NaCl doped in the grinding process at 800 ℃ for 1.5 h is of pure cubic spinel structure with an average particle size about 75 nm.