STRUCTURE AND PHYSICAL-PROPERTIES OF LITHIUM IRON-OXIDE, LIFEO2, SYNTHESIZED BY IONIC EXCHANGE-REACTION

Layered LiFeO2 was synthesized by ionic exchange reactions in molten s alts from alpha-NaFeO2; its structure was determined by X-ray and neut ron diffraction measurements and the magnetic properties were characte rized by magnetization measurements and Mossbauer spectroscopy. The re action conditions were clarified using various molten salts containing lithium, and a ''layered'' sample was obtained by a reaction in LiCl/ KCl molten salt at 400 degrees C for 0.5 h; a slightly higher reaction temperature of 500 degrees C gave an orthorhombic LiFeO2. Neutron dif fraction data of the ''layered'' LiFeO2 was fitted by a two-phase mode l with the alpha-NaFeO2 type and a spinel-related type. The Mossbauer spectroscopy indicated two different iron sites, being consistent with the two-phase model.