Annealing temperature Dependent on Morphology and Electrochemical Properties of ZnFe2O4 Nanoparticles Synthesized by Sol-Gel Method

A series of ZnFe2O4 nanocrystals were synthesized by sol-gel method. The surface morphology, structure and the electrochemical performace of the materials annealed in the temperature range of 500-800 degrees C were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), Multipoint N-2 adsorption-desorption experiment, constant current charging-discharging test, cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS) techniques. Consequently, the morphology and electrochemical performance of these materials are very sensitive to the sintering temperature. ZnFe2O4 material treated at 600 degrees C exhibits the initial reversible capacity of 1384.4 mAh g r and retains the highest capacity of 622 mAh g(-1) after 50 cycles. The superior electrochemical performance is attributed to its smaller charge transfer resistance of 43.9 Omega and higher lithium ion diffusion coefficient of 2.01 x 10(-15) cm(2) s(-)1, which due to the morphology with the smaller particle size and higher dispersibility.