采用溶胶-凝胶法制备Sr Ti_(0.6)Fe_(0.4)O_(3-δ),通过掺杂少量YSZ制备YSZ-Sr Ti_(0.6)Fe_(0.4)O_(3-δ)复相陶瓷。采用电化学工作站测试样品电子-离子混合传导及离子传导的阻抗谱和频谱特性,结果表明,YSZ-Sr Ti_(0.6)Fe_(0.4)O_(3-δ)在电子-离子混合传导过程中存在三种不同的极化过程,分别来自于晶粒,晶界和电极/样品,通过等效电路对阻抗谱的拟合,活化能分别为0.16 e V,0.62 e V和0.42 e V,随温度的升高,晶粒弛豫不明显,样品电阻主要由晶界的极化过程控制;在离子传导过程中,只存在一个晶界弛豫过程,晶界弛豫随温度的升高而减小,试样的弛豫时间为~0.13-0.29 s。
【英文摘要】
YSZ-Sr Ti_(0.6)Fe_(0.4)O_(3-δ)ceramic composite was synthetized by sol-gel method.Complex impedance and frequency spectra were investigated using an impedance analyzer.The result indicates that three polarization processes correspond to grain,grain boundary and sample/electrode,and the activation energies are 0.16,0.62 and 0.42 e V respectively during the ion-electron mix-conduction.The resistances of mix-conduction and ion conduction are also predominantly influenced by grain boundary.The relaxation time o...