Abstract This study is devoted to investigate the effect of Cu ions on the concentration of defect centres like free volume elements (which influence the physical properties of the glasses to a large extent), integrated in exotic lithium magnesium sulphophosphate glasses using positron (e+) annihilation lifetime spectroscopy (PAL) technique. Glasses of a particular composition viz., 20Li2SO4–20MgO–(60-x) P2O5: xCuO (0 ≤x ≤ 1.0 in mol%) were prepared by traditional melt-quenching technique. The analysis of the glass structure by means of spectroscopic studies, indicated that there is a gradual increasing fraction of Cu+ ions with increase of CuO content. The analysis further suggested that Cu2+ ions acted as modifiers in the glass network while Cu+ ions took part network forming position and increased the rigidity of the glass network. Later, positron annihilation decay profiles in the samples were recorded. 22Na isotope (0.1 MBq) was used as the positron source for this study. The obtained decay profiles were resolved in to three components and the corresponding intensity (I) and lifetime (τ) parameters were estimated and their variations with the concentration of CuO were plotted. The plots suggested that among the three intensity components, the third component (even though its contribution to the total intensity is small) exhibited the largest lifetime and further exhibited a decreasing trend with increase of CuO content. Moreover, radius of the cavity (R) and the fraction free volume (fv) entrenched in the glass matrix are found to decrease with increase of CuO concentration. The analysis of results of these studies in combination with the conclusions drawn from dielectric and related studies suggested a gradual decreasing concentration of Oh Cu2+ ions which induce free volume defects by acting as modifiers. Overall analysis of the results of PAL studies suggested increasing content of CuO facilitates the increasing rigidity or increasing corrosion resistance of lithium sulphophosphate glasses.

中文翻译：

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使用正电子湮没光谱法估计在 CuO 掺杂的硫代磷酸锂非晶体系中根深蒂固的纳米级空隙的浓度

摘要 本研究致力于研究 Cu 离子对自由体积元素等缺陷中心浓度的影响（在很大程度上影响玻璃的物理性质），利用正电子 (e+) 湮灭将其整合到奇异的硫代磷酸锂镁玻璃中。寿命光谱（PAL）技术。特定成分的玻璃，即 20Li2SO4–20MgO–(60-x) P2O5: xCuO（0 ≤x ≤ 1.0 mol%）是通过传统的熔融淬火技术制备的。通过光谱研究对玻璃结构的分析表明，随着 CuO 含量的增加，Cu+ 离子的比例逐渐增加。分析进一步表明，Cu2+离子在玻璃网络中起改性剂的作用，而Cu+离子则参与了网络形成位置并增加了玻璃网络的刚性。之后，记录了样品中的正电子湮没衰减曲线。22Na 同位素 (0.1 MBq) 用作本研究的正电子源。将获得的衰变曲线分解为三个分量，并估计相应的强度 (I) 和寿命 (τ) 参数，并绘制它们随 CuO 浓度的变化。该图表明，在三个强度分量中，第三个分量（尽管它对总强度的贡献很小）表现出最大的寿命，并且随着 CuO 含量的增加进一步表现出下降趋势。此外，发现空腔半径 (R) 和固定在玻璃基体中的自由体积分数 (fv) 随着 CuO 浓度的增加而减小。对这些研究结果的分析与从介电和相关研究得出的结论相结合，表明 Oh Cu2+ 离子的浓度逐渐降低，其通过充当改性剂而诱发自由体积缺陷。PAL 研究结果的总体分析表明，增加 CuO 含量有助于增加硫代磷酸锂玻璃的刚度或增加其耐腐蚀性。