Fermi level pinning in Co‐doped BaTiO ₃ : Part II. Defect chemistry models

A first-principles informed grand canonical defect chemistry model capable of accounting for non-stoichiometry and partial equilibration different sub-lattices is developed used to study Mg Mn doped, (Mg+Y) (Mn+Y) co-doped BaTiO3 elucidate the role Y in improving resistivity resistance degradation as observed by Ryu et al. Part I this series papers. The qualitatively captures behavior samples all conditions, reproducing carrier plateau increased BaTiO3, expected trends concentrations free oxygen vacancies with doping. These reflect differences characteristics, help explain substantially improved samples. Our adds mechanism proposed Yeoh that Fermi level pinned multivalent character MnTi giving insight into barium vacancies, site preferences dopants, complexes mechanism. insights provide a set criteria search sets co-dopants similar behaviors.