SPECTROSCOPIC INVESTIGATIONS OF ADSORPTION DURING FABRICATION OF AG (BI,PB)(2)SR2CA2CU3OX SUPERCONDUCTING TAPE/

Intrusion and inheritance of adsorbed gases during fabrication of silv er-sheathed (Bi, Pb)(2)Sr2Ca2Cu3Ox (2223) superconducting tape (Ag/Bi- 2223) are confirmed and studied by Fourier transform infrared spectros copy, x-ray photoemission spectroscopy and Auger electron spectroscopy . Handling in air of precursor powder (BPSCCO powder), composed of (Bi , Pb)(2)Sr2CaCu2Ox (2212), (Ca, Sr)(2)PbO4, (Ca, Sr)(2)CuO3, CuO and ( Bi, Pb)(2)Sr2CuOx (2201), causes the physisorption of CH2 or CH3, O-2, CO2, H2O and carbide and chemisorption of CO2 and H2O to form CO3 gro ups and hydroxyl on the powder. These adsorbates are inherited by the superconducting layer of the Ag/Bi-2223 tape and exist at grain bounda ries of the 2223 phase to form weak links, which dramatically degrade the intergrain critical current density (J(c)). Mechanisms of intrusio n and inheritance of adsorbates are systematically discussed. Our resu lts highlight the importance of atmosphere control during the handling of BPSCCO powder for obtaining high-J(c) tape.