Fabrication of YBa 2Cu 4O 8 from tartrate gel precursors

Abstract

Ceramic YBa 2Cu 4O 8 (Y-124) has been prepared by thermal decomposition of tartaric acid gels. The synthesis was performed in an oxygen atmosphere of 1 bar at a temperature, T s, of only 710°C. The onset temperature of the material to the superconducting phase was around T on≈83 K. Zero resistance was measured at T c0≈47 K. When increasing T s to 814°C an increase in T c0 to 72 K was observed. At temperatures T s =890° C the Y-124 phase starts to decompose.