Structure characterisation and lithium insertion in La0.33NbO3 perovskite

The A-site La0.33NbO3 perovskite was prepared by a solid-state reaction at high temperature. A superstructure was observed in both the XRD and electro n diffraction patterns of La0.33NbO3, which is related to the ordering of L a3+ ions and vacancies in the A sites. The La0.33NbO3 was used as the elect rode material in lithium cells. Approximately 0.67 lithiums can be electroc hemically inserted per La0.33NbO3 formula, which confirms the structural an alysis. The kinetic process of lithium insertion/extraction in a La0.33NbO3 electrode was determined by electrochemical impedance spectroscopy (EIS). he charge-transfer resistance (R-CT) decreases and the diffusion coefficien t increases with lithium insertion into La0.33NbO3 structure. (C) 1999 Else vier Science BN. All rights reserved.