Low-temperature synthesis of YBa2Cu3O7 –x films by the solution process using Y–Ba–Cu heterometallic alkoxide

Abstract

Superconducting YBa₂Cu₃O_{7 –x} films have been synthesized successfully at a low temperature of 600 °C by the solution process using the Y–Ba–Cu heterometallic alkoxide. The heterometallic alkoxide was synthesized by chemical modification and partial hydrolysis of component alkoxides. In gel films prepared from a heterometallic alkoxide solution, YBa₂Cu₃O_{7 –x} was obtained as a single phase at 600 °C under an argon atmosphere, whereas YBa₂Cu₃O_{7 –x} together with other crystalline phases was obtained from mixed alkoxide solutions. The heterometallic alkoxide precursor and the firing process under argon both proved effective for the low-temperature synthesis of single-phase YBa₂Cu₃O_{7 –x} films. The film fired at 800 °C for 6 h under argon followed by annealing at 450 °C for 24 h under oxygen, showed zero resistance at 74 K.