Structural, morphological and magnetic parameters investigation of multiferroic (1-x)Bi2Fe4O9- xCoFe2O4 nanocomposite ceramics

(1-x)Bi2Fe4O9- xCoFe2O4 (0.0≤ x ≤1.0) multiferroic nanocomposites were prepared by wet chemical procedures combining reverse chemical co-precipitation and Pechini-type sol-gel techniques followed by mechanical blending process. The XRD and SAED results showed that the diffraction patterns are perfectly indexed to the constituent phases present in composite samples. The crystallite sizes of the constituent phases were 35.4 and 39.4 nm for cobalt and bismuth ferrites, respectively. The characteristic peaks in FT-IR spectra confirmed formation and purity of all specimens. FESEM micrographs revealed the uniform phase distribution with the mean grain size of approximately 40 and 230 nm for CoFe2O4 and Bi2Fe4O9, respectively. TEM micrograph indicated suitable distribution in the as-prepared composite sample. The VSM results revealed that saturation and remnant magnetization increase by increasing CFO content in composites. Based on the results obtained from M-H curves, magnetic properties of composites did not originate only from linear combination of parent phases. The recorded coercivity values of all nanocomposites, for example 1443 Oe for x = 0.4 were higher than those of each parent phase i.e. 708 Oe for CoFe2O4 and 149 Oe for Bi2Fe4O9, showing a noticeable improvement in magnetic properties.