Synthesis and physico-chemical properties of phase-pure ceramic LuBa2Cu3O7−δ

Up to now all ceramics of REBa2Cu3O7−δ (RE = Y and rare-earth elements) were prepared at temperatures of about 900–950 °C except Lu123. LuBa2Cu3O7−δ could not be prepared as single-phase ceramic. In the present study, we have developed the preparation conditions to synthesize phase-pure Lu123 ceramics. We have measured the resistivity of Lu123 (Tc = 92.1 K) at different temperatures, determined the enthalpies of reaction including LuBa2Cu3O7−δ by solution calorimetry and have studied the thermodynamic stability of this compound.