Preparation of polypyrrole-coated CuFe2O4 and their improved electrochemical performance as lithium-ion anodes

CuFe2O4 network, prepared via the electrostatic spray deposition technique, with high reversible capacity and long cycle lifetime for lithium ion battery anode material has been reported. The reversible capacity can be further enhanced by coating high electronic conductive polypyrrole (PPy). At the current density of 100 mA.g(-1), Li/CuFe2O4 electrode delivers a reversible capacity of 842.9 mAh.g(-1) while the reversible capacity of Li/PPy-coated CuFe2O4 electrode increases up to 1106.7 mAh.g-1. A high capacity of 640.7 mAh.g(-1) for the Li/PPy-coated CuFe2O4 electrode is maintained in contrast of 398.9 mAh.g(-1) for Li/CuFe2O4 electrode after 60 cycles, which demonstrates good electrochemical performance of the composite due to the increase of electronic conductivity. The electrochemical impedance spectroscopy (EIS) further reveals that the Li/PPy-coated CuFe2O4 electrode has a lower charge transfer resistance than the Li/CuFe2O4 electrode.