非晶锂离子导体B2O3-0.7Li2O—0.7LiCl-xAl2O3晶化过程的正电子湮没一维角关联辐射研究

本文用中国第一台正电子湮没辐射一维角关联实验装置,测量了非晶锂离子导体B₂O-0.7Li₂O-0.7LiCl-xAl₂O₃(x=0.15;0.10;0.05)晶化过程中各条正电子湮没辐射的一维角关联曲线,并对归一化的电子动量分布进行了线形参数的计算,从其S参数同样能推测出该离子导体在晶化过程中缺陷浓度的变化。非晶离子导体B₂O₃-0.7Li₂O-0.7LiCl-xAl₂O₃的实验结果表明,Al₂O₃组分不同,对非晶态样品在室温下一维角关联曲线的S参数亦无较大影响。完全晶化后,一维角关联曲线的S参数均有很大下降。在晶化过程最初期,无论Al₂O₃含量多少,S参数都明显略增;到晶化温度附近,仅对Al₂O₃含量较多的非晶,S参数反常增高。这些结果验证和补充了测正电子平均寿命得出的结论。由此初步证实了界面层有大量缺陷的物理图象。 关键词：

INVESTIGATION ON CRYSTALLIZATION PROCESS OF AMORPHOUS LITHIUM IONIC CONDUCTOR B2O3-0.7Li2 O-0.7LiCl-xAl2O3 WITH ONE DIMENSION ANGULAR CORRELATED POSITRON ANNIHILATION RADIATION

One dimension angular correlated positron annihilation radiation curves of amorphous lithium ionic conductor B₂O₃-0.7Li₂O-0.7LiCl-xAl₂O₃ (x = 0.15, 0.10, 0.05) during the crystallization process have been measured, and the linear parameters S in normalized dispersion of electron momentum have been calculated. From the parameters S we can also disclose the variations in defect-density during the crystallization process.Experimental results show that the parameters S at room temperature are not Largely affected by the content of Al₂O₃, each and all greatly decrease after full crystallization process, each and all slighly increase at the beginning of crystallization, but then increase anomalously at about 400-450℃ only when x= 0.15. These results verify and complement the results obtained from measuring average positron lifetime. From them we are convinced of the physical picture that the boundary layer contains a lot of defects.