Role of cadmium and cerium substitution on structural, morphological, DC electrical conductivity, and magnetic properties of cobalt (Co1–xCdxCeyFe2–yO4) spinel nanoferrites
摘要
In the present investigation, Co1–xCdxCeyFe2–yO4 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0; y = 0.0 and 0.1) nanoferrites were synthesized by solution combustion method. Typical X-ray diffractograms confirmed the single-phase cubic spinel phase of the synthesized samples. The crystallite size and lattice parameter were found in the ranging from 20.89 nm to 50.98 nm and from 0.8322 nm to 0.8412 nm, respectively. FTIR spectroscopy exhibits two characteristic absorption bands υ1 and υ2 due to stretching frequencies of tetrahedral and octahedral sites, respectively. Scanning electron microscopy and energy-dispersive X-ray spectroscopy revealed well-formed, agglomerated grains with existence of all the components: Co, Cd, Fe, O, and Ce without any impurity. The grains were almost spherical and ranged from 120.8 nm to 211.3 nm. The DC electrical conductivity inferred the semiconducting behavior and distinct phase of conductivity attributed to the magnetic phase change with temperature. The activation energy obtained from conductivity plots in paramagnetic region is found to be more than that in ferrimagnetic region. Vibrating sample magnetometer was employed to probe the magnetic properties of the samples at room temperature confirmed ferrimagnetic ordering and magnetization was explained on the basis of spin canting. The maximum values of saturation magnetization, remnant magnetization, and magnetic moment, respectively, were 108.7 emu/g, 43.861 emu/g, 4.9808, and 1.213 μB observed for x = 0.4; y = 0.0 and 110.71 emu/g, 37.130 emu/g, 4.8454, and 1.1838 μB for x = 0.4; y = 0.1, respectively, thereafter decreased ascribed to change in canting angle. However, in nanoregime, CdFe2O4 exhibits weak ferrimagnetic behavior at 300 K. These nanoferrites are suitable materials for magnetic memories, filters, and transformer cores.