CuCl_2-石墨层间化合物导电性能及其机理研究

THE ELECTRICAL PROPERTY AND ITS MECHANISM OF INTERCALATION COMPOUNDS OF CuCl 2 

以２—３μｍ石墨作主体材料合成了不同阶结构的ＣｕＣｌ２ＧＩＣｓ，并用四探针法测量其导电性能，所得ＧＩＧｓ电导率是石墨原料的１５—２２倍．阶数升高，电导率递增．微区成分分析发现：氯和铜离子为非计量比例，ＧＩＣｓ中存在氯离子空位，提高了载流子的浓度．ＧＩＣｓ氯离子空位在ｃ轴方向联通形成格架，增加了该方向载流子活动空间；ＸＰＳＥＳＣＡ分析证实：ＧＩＣｓ中阳离子价态有变化．ＧＩＣｓ将良导体的石墨层与绝缘体的氯化物层在分子尺度上结合起来，所形成的阶结构相当于许多导体和绝缘体层组成的“三明治”结构，产生化学键薄弱的通道，提供了垂直ｃ轴方向的载流子通道，隧道效应和格架空间提供了载流子活动空间。

Abstract The electrical property of 1 4 stages of intercalation compounds of CuCl 2,which were synthesized with 2 3μ m graphite powder,was measured by the four probe method.Their conductivity was 1 5 2 2 times as that of their host material,graphite.The higher the stage,the higher the conductivity.The microanalysis of chemical compounds by the X ray energy spectrum scanning analysis of TEM testified that the atom ratio of chlorine and cupric was non stoichoimetric.The vacancy of the chlorine anion in the GICs increased the concentration of the carrier particle.They link up in c axis,and enlarged the activity space of the carrier particle.The exchange of the electrovalence of the cupric ion has been testified by XPS ESCA.Graphite and chloride in the stage structure,seem to be the conductor and insulator,which form the “sandwich” structure.This special structure produced a weak chemical bond belt and provided the carrier space in the perpendicular direction to the c axis.These factors in and vertical to the direction of c axis together increased the electrical properties.