Electrochemical and microstructure properties of Er-doped CaZrO3

To understand electrochemical properties of the rare earth-doped CaZrO3 system in more detail, a solid-state electrolyte Er-doped CaZrO3 was successfully prepared using solid-state reaction method at the temperatures of 1673 K and 1823 K for 10 h. The microstructures and electrochemical properties of these materials were systemically investigated. The results from structural analysis showed that the electrolyte has a pure perovskite phase structure. According to the H/D isotope effect, protons were determined as the dominant charge carriers in hydrogen atmosphere between 773 and 1273 K. The electrochemical impedance spectroscopy test showed that ionic electrical conductivities are approximately 1.86 × 10−8 ~ 2.93 × 10−4 S/cm at 773 ~ 1273 K, and ionic conductance activation energy (Ea) is in the range of 0.823–1.416 eV, Furthermore, ionic electrical conductivity decreases with increasing Er2O3 doping amount, which is completely different from that of In2O3 or other dopant-doped CaZrO3. The abnormal phenomenon is associated with the defect association introduced by incorporation of Er2O3 into CaZrO3 lattice on the basis of the DFT calculation.