Li2O-P205O-V2O5系统非晶材料电学性质与磁共振研究

本文对Li₂O-P₂O₅-V₂O₅系统非晶态中的几组试样进行了电导率、核磁共振及顺磁共振测试。实验分析表明非晶态的log(σΤ)-1/Τ曲线都是由两个直线段构成。电导率在转变温度以后的“晶化前期”异常增大,这归因于该阶段非晶态结构有序化程度增加所致,利用ESR实验结果对非晶态进行钒离子价态分析表明,该系统非晶态中钒离子仅以V⁴⁺和V⁵⁺状态存在。固定P< 关键词：

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

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.