CHARACTERIZATION OF SPINEL LITHIUM MANGANITE PREPARED BY CITRATE SOL-GEL METHOD

The powder characteristics of LiMn2O4 prepared by the citrate sol-gel method have been investigated. The optimum pH for the preparation of h omogeneous citrate gel was calculated by the theoretical consideration of thermodynamic equilibrium constants for metal-citrate complexes an d metal salts. The obtained citrate gel was prefired at 300 degrees C and calcined at 300-700 degrees C for 1 h. The obtained powders were c haracterized by TG/DSC, FT-IR spectrometer, X-ray diffractometer, SQUI D magnetometer, SEM, and particle size analyzer. It was observed that the mixed phases of spinel LiMn2O4 and Mn3O4 were transformed into spi nel LiMn2O4 phase and the vibrational bands due to the carbonate and n itrate were also disappeared over 400 degrees C. At temperatures below 150 K, inverse molar susceptibilities of every sample began to show a n antiferromagnetic ordering of Mn magnetic moments.