Cation Doping into the Superconducting Bi-Sr-Ca-Cu-O Ceramics Using the Solid Oxide Electrochemical Doping Method

Abstract

Electrochemical cation doping into the bismuth oxide superconductor (Bi₂Sr₂CaCu₂O_y, BSCCO) was carried out using the solid oxide electrochemical doping (SOED) method, where electrolysis system consists of Anode(Ag)/M-β"-Al₂O₃/BSCCO/Na-β"-Al₂O₃/Cathode(Ag). Various cations (Ag⁺, K⁺, Zn²⁺) were doped together with substitution for Sr²⁺ in BSCCO. The doping occurred only in the grain boundaries of the ceramics when the monovalent cations were used as the dopant. On the other hand, Zn²⁺ was doped in the grain bulk as well as the grain boundaries under the same electrolysis condition. This doping mechanism is briefly discussed.