Proton Conductivity in Perovskite Oxides

Perovskite oxides offer in almost all respects a wide variety of properties because of the structure’s ability to host varying cations, substitutions, nonstoichiometry, and defects of many kinds. Proton conduction, resulting from oxide ability to dissolve protons from water vapor or hydrogen, is no exception: Some perovskites contain virtually no protons at all and are thus barriers to protons, hydrogen, and water vapor. Other perovskites are dominated by proton defects to high temperatures and are predominantly proton conductors.