Solution Processing of YBa2Cu3OT7-x Thin Films

ABSTRACTThe aim of this work was to develop a non-vacuum chemical deposition technique for YBa2Cu3O7-x (YBCO) coated conductors on rolling-assisted biaxially textured substrates (RABiTS). We have chosen the metal-organic decomposition (MOD) and sol-gel precursor routes to grow textured YBCO films. In the MOD process, yttrium 2-ethylhexonate, barium neodecanoate, copper 2-ethylhexonate and toluene were used as the starting reagents. YBCO films processed by the MOD method on SrTiO3 (100) single crystal substrates were predominately epitaxial and consisted of c and a-axis oriented material. Films have a TC,onset of 89K and the best superconducting transition temperature of 63K. Films pyrolyzed at 525 °C and subsequently annealed at 780 °C in P(O2) of 3.5 × 10−4 atm contained YBCO phase predominately in a-axis orientation. In the sol-gel route, yttrium-isopropoxide, barium metal, copper methoxide and 2-methoxyethanol were used as the starting reagents. Sol-gel YBCO films on SrTiO3 substrates were epitaxial and c-axis oriented.

Metallo-Organics Derived Tractable Resins for Ybco Superconducting Fiber Fabrication

ABSTRACTSoluble resins were prepared by controlled hydrolysis of yttrium isopropoxide, barium isopropoxide and copper ethylhexanoate. The resins were converted to cohesive, viscous, fluid and precipitated states by the addition of different combinations of binary polar and non-polar organic solvents. Viscosity and spinnability of the resins were critically dependent on the solvent constituents. Continuous pre-ceramic fibers were spun from these resins and single phase YBa2Cu3Oy superconducting fibers with Tc=91.5K and ΔT=1.5K have been obtained.