Oxygen and proton transport properties of La_5.4WO_11.1-δ are investigated using electrical conductivity relaxation. Chemical diffusion coefficients and surface exchange coefficients of both hydrogen and oxygen presumed to govern conductivity relaxation are extracted from fitting the two-fold conductivity relaxation observed after hydration/dehydration steps at fixed oxygen partial pressure to the model equations. Surprisingly, the kinetic parameters obtained from fitting are found to depend on the magnitude of the current used in the measurements. A two-fold relaxation behavior with characteristics depending on the magnitude of the current is also observed after oxidation/reduction steps under dry conditions. Furthermore, at fixed temperature, oxygen and water partial pressures, the conductivity is found to exhibit relaxation behavior after a current step, while the apparent steady-state conductivity is found to depend on the applied current. The observations are attributed to the use of gold electrodes in the experiments and associated interfacial capacitances. It is obvious from this study that the use of partially ion-blocking electrodes in conductivity and conductivity relaxation measurements on mixed ionic-electronic conducting oxides with prevailing ionic conduction may lead to erroneous results and interpretations.

_{La 5.4} WO _{11.1- δ}的氧和质子传输特性使用电导率弛豫进行研究。假定控制电导弛豫的氢和氧的化学扩散系数和表面交换系数是通过将在固定氧分压下水合/脱水步骤后观察到的双重电导弛豫与模型方程拟合得到的。令人惊讶的是，发现从拟合中获得的动力学参数取决于测量中使用的电流大小。在干燥条件下的氧化/还原步骤之后，还观察到具有取决于电流大小的特性的两倍弛豫行为。此外，在固定温度、氧气和水分压下，发现电导率在当前步骤后表现出弛豫行为，而表观稳态电导率取决于施加的电流。观察结果归因于在实验中使用金电极和相关的界面电容。从这项研究中可以明显看出，在具有主要离子传导的混合离子电子导电氧化物的电导率和电导弛豫测量中使用部分离子阻挡电极可能会导致错误的结果和解释。