Epoxy-Encapsulated Ceramic Superconductor Microelectrodes

A procedure is outlined for fabricating well-behaved microelectrodes from ceramic pellets of YBa₂Cu₃07 and Bi₂Sr₂CaCu₂0₈which involves systematic polishing of an epoxy-encapsulated superconductor chip, under Et₄NC104/acetonitrile solution, to a potentiometric end point Voltammetry of the resulting microelectrodes in acetonitrile is illustrated and compared to that arising from alternative superconductor electrode geometries. The microelectrodes have active electrode surface areas ranging from 2 x 10^-6to 3 x 10^{- 4}cm², as characterized electrochemically and microscopically. The results discussed herein are significant steps toward developing the methodology necessary to study the electrochemical response of high temperature superconductor phases at temperatures below their superconductor critical temperature.