Effect of carbon coating on improved electrical and electrochemical performance of Li ₃ Co ₂ SbO ₆

Abstract We reported a novel high voltage cathode having layered structure and manifold improvement (144%) in electrochemical performance on carbon coating Li 3 Co 2 SbO 6 . The carbon-coated Li 3 Co 2 SbO 6 has been prepared using a high temperature solid-state method in an air medium with appropriate stoichiometry of the oxide and carbon source (sucrose). The x-ray diffraction and high-resolution transmission electron microscopy results have confirmed homogeneous carbon coating on oxide (Li 3 Co 2 SbO 6 ) surface without disturbing phase, structure and morphology. The immediate effect of carbon coating resulted in electrical conductivity enhancement of the carbon coated Li 3 Co 2 SbO 6 by four order of magnitudes ∼2.79 × 10 −4 Scm −1 at room temperature vis-a-vis pristine Li 3 Co 2 SbO 6 . The electrochemical performance of the carbon coated Li 3 Co 2 SbO 6 has shown sustainable improvement indicating redox activity by more than one Li + transaction. The carbon coated Li 3 Co 2 SbO 6 cathode exhibited an initial discharge capacity of 110 mAhg −1 compared to 45 mAhg −1 for its pristine counterpart. The improvement in electrochemical capacity on carbon coating, as reported in this work, is the highest ever compared to prior literature reports on Li 3 Co 2 SbO 6 .