Tunneling Structure and Phase-Transformation Dynamics of Two-PhaseFerrite of ZnFe2O4/Fe2O3

The nanostructure ferrites of two-phase ZnFe2O4/Fe2O3 were prepared by the sol-gel method. The structure was analyzed by X-ray diffraction (XRD) and high-resolution electron microscope (HREM). The results indicate that two-phase ferrite is the necessary condition to form tunneling structure. Non-Ohmic character ofI-V curve and magnetoresistance effect of two-phase ferrite also show tunneling character. The tunneling structure was directly observed by HR.EM in two-phase ferrite that insulating layer of α-Fe2O3 located in interface between ferrets. Approved deeply by phase-transformation dynamics, crystallization of α-Fe2O3 is controlled by the interface or surface of ZnFe2O4 crystallite.