The compound Cr 1.4 Fe 0.6 O 3 has been synthesized through mechanical alloying of Cr 2 O 3 and -Fe 2 O 3 powders and subsequent thermal annealing. The XRD spectrum, SEM picture and microanalysis of EDAX spectrum have been used to understand the structural evolution during alloy formation. The alloyed samples have been matched to rhombohedral structure with R3C space group. The observation of a modulated magnetic order confirmed the systematic diffusion of Fe atoms into the Cr sites of lattice structure. A field induced magnetic behaviour has been noted in the field dependence of magnetization data of the annealed samples. This feature is significantly different from that of the mechanical alloyed samples. The experimental results also provided the indications of considering the present material as a potential candidate for opto-electronic applications.

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MgFe 2 O 4 -C composite nanofibers were prepared via electrospinning technique followed by carbonization at 600 8C. Thermogravimetric-differential thermal analysis (TG-DTA) results showed ignition, decomposition and carbonization temperatures of the as-grown fibers. Formation of the nanocrystalline phase of the MgFe 2 O 4 over the amorphous phase of the carbon fibers sample was confirmed from the analysis of the measured XRD results. FE-SEM images of the as-spun and calcined fibers sample showed that the formation of one dimensional (1-D) MgFe 2 O 4 -C composite nanofibers and the formed 1-D nanofibers were well interconnected with high porous structured morphology. The electrochemical properties of the MgFe 2 O 4 -C composite nanofibers sample were tested as an anode material for lithium-ion battery. Lithium-ion battery made up of the newly developed MgFe 2 O 4 -C composite nanofibers sample, used as an anode material, showed discharge capacity of 575 mAh g À1 at a current density of 100 mA g À1 after 20 th cycles. Further, the discharge capacity of the lithium-ion battery also measured at a high current density of 1 A g À1 and it was found to be 433 mAh g À1 even after 85 cycles. Also, the lithium-ion battery showed exceptional reversible capacity with the coulombic efficiency of 99.6% even after 85 cycles at a high current density of 1 A g À1 . Hence the electrochemical properties suggest that the newly developed MgFe 2 O 4 -C composite nanofibers can be used as high capacity anode materials for lithiumion batteries.