Electrochemically assessed corrosion reactivity of YBa 2Cu 3O 7 electrodes

Abstract

This paper describes a series of electrochemical measurements designed to explore the surface reactivity of the oxide superconductor YBa 2Cu 3O 7. The electrochemical response of electrodes prepared from this material was found to be highly dependent on both the method of surface treatment and on the amount of water in the electrolytic fluid. In the absence of water, YBa 2Cu 3O 7 behaved as a normal metal electrode and reproducible voltammetry was obtained in the potential window of 1.3 V to −1.4 V vs. SCE. At these potentials, faradaic electron transfer reactions for solution dissolved redox couples were readily observed at YBa 2Cu 3O 7 and were similar in behavior to those obtained at noble metals such as Pt. At potentials outside this window, degradation of the electrode surface occurred. In addition, a very sensitive method has been developed for evaluating the quality of the surface of high temperature superconductors based on monitoring Δ E p values in cyclic voltammetry.