Sm对PbTiO_3陶瓷的气相扩渗及其电性能研究

Gas Penetration of Sm to PbTiO_3 Ceramics and Their Electric Characteristics

为了提高PbTiO3陶瓷的导电性,首次采用气相法对PbTiO3陶瓷扩渗Sm元素。经Sm扩渗,PbTiO3陶瓷的导电性发生了变化,其室温电阻率从2.0×1010Ω·m下降为3.8×102Ω·m。随着温度升高,晶粒电阻和晶界电阻逐渐降低,导电性更强,并有向导体过渡的趋势。经XPS测试分析,证实了Sm扩渗PbTiO3陶瓷体系中Pb、Ti、O、Sm均有变价,因而导致了PbTiO3陶瓷导电性的提高,测试结果还首次给出了Sm扩渗PbTiO3陶瓷体系中各元素的结合能位置。

In order to improve the electric conductivities of PbTiO_3 ceramics, the new techniques of penetration of Sm element in gas phase were adopted. The results show that the penetration of Sm element make the electric characteristics of PbTiO_3 ceramics change obviously. The resistivitiy of Sm-penetration PbTiO_3 ceramics decrease obviously, when the Sm element content is 2%, the penetration temperature is 960°C and the penetration time is (4 h), the resistivity decreases to the smallest, which changes from 2.0×10^(10)Ω·m to 3.8×10~2Ω·m. The grain resistance and the grain boundary resistance decrease with increase in temperature, the electrical conductivity is better,and is inclined to conductor. Through X-ray photoelectron spectrum(XPS), the binding energy of the elements in Sm-penetration PbTiO_3 ceramics was analyzed,the results indicate that the quantivalence of Pb, Ti, O, Sm in (PbTiO_3) ceramics is variable,and result in the improving of the conductibility of PbTiO_3 ceramics.