Structural and microstructural study of the formation of the solid solution LixNi1-xO

Scanning electron microscopy and X-ray powder diffractometry have been used to characterize solid solutions of the type LixNi1-xO. Structural and profile parameters were refined from X-ray data to study both the composition and the homogeneity of the mixed oxides. It is shown that non-homogeneity is responsible for the appearance of broad and asymmetrical diffraction peaks and that better agreement between calculated and observed patterns is obtained if non-homogeneous mixed oxides are treated as if they consisted of solid solutions of different composition. The morphology, the mean composition and the homogeneity of the solid solutions as well change (in a non-monotonous way) as a function of the time of the isothermal treatment (T=800 degC) after which the samples were obtained. (author). 15 refs.; 5 figs.; 2 tabs