CAJ | 학술논문

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.
채용용효-응효방법성공제비료Sr적체대화합물Y1?xSrxCoO3(x=0,0.01,0.05,0.10,0.15,0.20),계통지연구료20—720 K온도범위내Y1?xSrxCoO3적전조솔온도관계.연구표명,수착Sr적체대함량적증가, Y1?xSrxCoO3적전조솔신속지강저,저주요시유우재류자농도적증가인기.양품x=0화0.01재저우330화260 K적온도범위내,전조솔여온도지간만족지수관계lnρ∝1/T,획득도전격활능분별위0.2950화0.1461 eV.연이,실험현시lnρ∝1/T 관계부성립우중참잡양품적고온구;재저온구막특정률lnρ∝T?1/4성립,차표명중참잡인입세루,도치대량국역태적형성.근거막특T?1/4정률의합실험수거,평고료국역태밀도N(EF),타수착참잡량적증가이증가.
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.