Effect of Calcination Temperature on the Physical Properties of Layered LiNiO₂ Prepared by Solid-State Reaction Method

Abstract

A layered structure compound LiNiO2 material is synthesized by the solid-state reaction method under air atmosphere in the temperature range from 750 °C to 850 °C using Li2CO3 and NiO as the starting materials for 20 hours. The physical properties of the synthesized powder are investigated by X-ray diffraction (XRD), Field effect scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopic (FT-IR) techniques. The results of XRD patterns possessed the α-NaFeO2 structure of the rhombohedral system (space group, ) with no evidence of any impurities. The morphological features of the powders are characterized by field effect scanning electron microscopy (FESEM). The particles of LiNiO2 powder are generally in the form of a smoothly edged polyhedron and their average grain size is approximately 2 - 3 μm. The FT-IR spectroscopic data of LiNiO2 reveal the structure of the oxide lattice constituted by LiO6 and NiO6 octahedra. In general, from this study, we conclude that the LiNiO2 synthesized by solid state reaction method at different temperatures to increase in the sintering temperature. The lattice constant is increased, while the sintering temperature is increased. The maximum and minimum intensity ratios of XRD spectra shows that the optimum calcination condition is 800°C for 20 h. At 750-850°C, the particle size distribution is in the range of 2 - 3 μm.