Characterization and synthesis of Y0.9Ca0.1Ba1.8Sr0.2Cu3O7−δ via combining sol–gel and solid-state route

The role of sol-gel method and doping Ba in the drastic reduction of the annealing time and the improvement of the coupling between grains of Bi1.6Pb0.4 Sr2-xBaxCa2Cu3Oy superconductor

“…Moreover, the starting solution in the sol-gel method is a homogeneous mixture of the metal ions in the desired stoichiometry ratio. By using the SGR method, not only does the phase purity improves, the grain size also decreases [17,18]. Study of superconductivity properties of Bi1.6Pb0.4Sr2-xBaxCa2Cu3Oy superconductor synthesized by the sol-gel method in this research indicated that the optimum annealing time is t = 48 h, whereas for example in the solid-state reaction (SSR) method, annealing times are t = 270 h [6], t = 170 h [2] and t = 96 h [19].…”