Lithiation-delithiation properties of new compound LiNi0.5Ti0.5O2 with cubic structure

A new compound Li-Ni-Ti oxide-based material (LiNi0.5Ti0.5O2) with cubic structure was prepared by solid state reaction at 900 degrees C. Powder X-ray diffraction (XRD) was used to determine the phase purity and structure of the material. The Bragg peaks of LiNi0.5Ti0.5O2 can be indexed based on a cubic unit with dimension a = 4.142 angstrom, belonging to space group Fd3m (SG number 225). X-ray photoelectron spectroscopy (XPS) study showed that the chemical valences of Ni and Ti were +2 and +4, respectively. The electrochemical testing indicated that the Li+ ions in LiNi0.5Ti0.5O2 cannot be extracted until 4.8 V. However, two initial Li ions per LiNi0.5Ti0.5O2 can be intercalated into LiNio.5Tio.502 and one Li+ ion can be extracted reversibly. (c) 2005 Elsevier B.V. All rights reserved.