中文摘要：

采用溶胶-凝胶方法成功制备了Sr的替代化合物Y1-xSrxCoO3 （x=0, 0.01, 0.05, 0.10, 0.15, 0.20）, 系统地研究了20–720 K温度范围内Y1-xSrxCoO3的电阻率温度关系. 研究表明, 随着Sr的替代含量的增加, Y1-xSrxCoO3的电阻率迅速地降低, 这主要是由于载流子浓度的增加引起. 样品x=0和0.01在低于330和260 K的温度范围内, 电阻率与温度之间满足指数关系lnρ∝1/T, 获得导电激活能分别为0.2950和0.1461 eV. 然而, 实验显示lnρ∝1/T关系仅成立于重掺杂样品的高温区; 在低温区莫特定律lnρ∝T-1/4成立, 且表明重掺杂引入势垒, 导致大量局域态的形成. 根据莫特T-1/4定律拟合实验数据, 评估了局域态密度N（EF）, 它随着掺杂量的增加而增加.

英文摘要：

The temperature dependences of electrical resistivity for Sr-substituted compounds Y1-xSrxCoO3 （x=0, 0.01, 0.05, 0.10, 0.15, 0.20）, prepared successfully by sol-gel process, are investigated in a temperature range from 20 to 720 K. The results indicate that with the increase of doping content of Sr the resistivity of Y1-xSrxCoO3 decreases remarkably, which is found to be caused by the increase of carrier concentration. In a temperature range below 330 and 260 K for the sample x=0 and 0.01, the relationship of resistivity versus temperature processes exponential relationship lnρ∝1/T, with conduction activation energy 0.2950 and 0.1461 eV for the sample x=0 and 0.01 respectively. Moreover, experiments show that the relationship lnρ∝1/T exists only in high-temperature regime for the heavily doped samples; at low temperatures Mott’s law lnρ∝T-1/4 is observed, indicating that heavy doping produces strong potential, which leads to the formation of considerable localized state. By fitting the experimental data to Mott’s T-1/4 law, the density of localized states N（EF） at Fermi level is estimated, which is found to increase with doping content increasing.