The conduction mechanism of Li–Ga ferrite

Gallium substituted lithium–ferrite having the general formula Li0.5Fe2.5 − xGaxO4 with 0.0 ≤ x ≤ 0.5 in steps of 0.1 were synthesized by the standard ceramic technique. The variation of DC and AC conductivities with temperature have been reported in a wide range of temperature from room temperature 293 K up to 1023 K in static air. AC measurements were carried out in a wide range of frequencies from 100 Hz up to 1 MHz. The values of activation energies for the compositions containing gallium approximately is twice the activation energy of x = 0. The electron mobility in Li0.5Fe2.5O4 shows an activation energy of 0.36 eV, while the activation energy of Li–Ga ferrites are ranging from 0.64 to 0.77 eV. These values are due to a narrow-band conduction mechanism and a formation of small polaron.