High-temperature electrical conductivity and defect structure of donor-doped a-Al 02 3

direst current electrical conductivity and the corres-ponding ionic and electronic transference numbers deduced from emf measurements of oxygen and/or hydrogen concentration cells with al 2 o3 as an electrolyte are used to study the defect structure of al 2o3 doped with hydrogen and yttrium. Hydrogen, is found to be a donor, and is used to exactly compensate an acceptor dominated material in order to determine the parameters of native ionic and electronic disorder inal2o3.