FABRICATION OF OXOCUPRATE SUPERCONDUCTOR MICROELECTRODES FOR SUB-T-C USE

The technique of partial resin encapsulation is described for the dire ct fabrication of cryorobust oxocuprate microelectrodes from bulk cera mic samples, here Bi2Sr2CaCu2O8-delta,Bi2Sr2Ca2Cu3O10-delta, and YBa2C u3O7-delta. Cyclic voltammetry is used in tests of the electrochemical response at 295 K (ferrocene in acetonitrile/NBu(4)BF(4)), affording approximated disk radii 2.9, 37.0, and 32.5 mu m, and at 123 and at 10 3 K (ferrocene in chloroethane/tetrhydrofuran/LiBF4). Some nonideality in the 295 K responses results from electrode porosity and, at the sm allest electrodes, defects in the HTSC/resin seal. Acceptable sub-T-c responses show these problems to be irrelevant in the high viscosity o f the electrolytes at low temperature. These microelectrodes usefully advance the emerging study of electrochemistry on superconducting elec trodes by responding to free-solute electroactives at < T-c.