关键词：汽车；氧传感器；离子导电；电化学阻抗谱；钐掺杂氧化铈；
摘 要：The ionic conductive behavior of the electrolyte was analyzed on the basis of electrochemical impedance spectroscopy (EIS) test,and the interaction of working temperature,defect microstructure and ionic conductivity was investigated.Accordingly,the SDC displayed an ionic conductivity of 0.029 S cm-1 at 750 ℃.It was suggested that the nano-crystalline could shorten the transfer distance of the charge carriers.Furthermore,the structural change of the polycrystal boundaries with the temperature was a key factor which promoted the oxygen ionic conductivity.