Structural properties of SrCeO₃/SrZrO₃ proton conducting superlattices

High temperature proton conducting oxides having distorted-perovskite structure show high protonic conduction at elevated temperatures, and have been applied in the sensors and energy conversion devices. In order to control the distortion of crystal structure, we have fabricated SrZrO₃-SrCeO₃ superlattices (SLs) by laser ablation technique and have investigated the structural and electrical properties. The epitaxial growth on MgO (110) substrates is confirmed from 4-axis X-ray diffraction analysis. From the dependence of lattice constant on superlattice periodicity, it is confirmed that critical periodicity make strained superlattice is about 15-20 nm for system SrZrO₃/SrCeO₃ on MgO (110).