Abstract
Glasses of the formula 40Li(2)O center dot xSb(2)O(3)center dot(60-x)B2O3 (0 <= x <= 40 mol%) were prepared using the melt quenching technique. XRD, FTIR spectroscopy, SEM, density and dc conductivity were studied. A phase separation was observed in as-prepared glass samples that contain a concentration of Sb2O3 >= 25 mol%. Moreover, crystalline phases of Li5Sb3O8, Li3SbO4 and LiSbO3 were found in the 40Li(2)O center dot 40Sb(2)O(3)center dot 20B(2)O(3) glass sample after thermal treatment at 600 degrees C for 4 h. N (4) decreased slightly with increasing Sb2O3 content. The contribution to N (4) from Li2O and Sb2O3 was separated. The negative contribution of Sb2O3 to N (4) was due to the association of Sb2O3 and Li2O to form Li5Sb3O8, Li3SbO4 and LiSbO3 phases and acting as a former. The formed Li5Sb3O8, Li3SbO4 phases having low migration energy and rich with Li+ ions exhibited a high mobility. Density and molar volume increased with increasing Sb2O3 content. The abrupt increase in the conductivity by about 4 orders in magnitude for Sb2O3 >= 25 mol% is correlated with the presence of clusters rich by Li+ and Sb+3 ions that have low migration energies and the increase in the free volume.