STUDY ON THE ELECTRICAL PROPERTIES AND MAGNETIC RESONANCE OF NONCRYSTALLINE MATERIALS IN THE Li2O-P2O5-V2O5 SYSTEM

Abstract

The conductivity, NMR and ESR spectra of the specimens in the Li2O-P2O5-V2O5 system are measured. Conductivity measurements on these materials reveal a sharp break in the slope of the curve of log conductivity vs reciprocal temperature in the vicinity of transformation temperature. And the conductivity shows abnormal increasemant during pre-crystallization process above the break point, this is caused by the increase of degree of ordering during that process. Valency state analysis of vanadium ions by ESR show that only V4+ and V5+ ions exist in these materials. When P2O5/V2O5 mote ratio is fixed, the 7Li-NMR and V4+-ESR line width narrow clown continonsly with increasing lithia content, this indicates that ionic conductivity increases and electronic conductivity decreases continously in these materials. At first, conductivity de-creases with the increasement of lthia content, but it increases when lithia content exceeds 30 mol%. The conduction mechanism of these materials was also discussed.