A Study on Exchange Current Density of ZrO_2 Solid Electrode at High Temperature

A kind of symmetrical electrochemical cell of the type M, MxOy |ZrO2(MgO)| M, MxOy was used to study the polarization characteristic of solid state reference electrodes at high temperature.Experimental results show that the variation of overpotential with polarization current is linear.The exchange current desitics for the Mo/MoO2, Cr/Cr2O3, Ni/Ni/O and Co/CoO electrodes, in the order named, are decrcasing. The exchange current densities of all kinds of electrodes are also increasing with the increase of metal ratio in reference electrodes and temperature. The activation energy of the electrode reactions was calculated.