Studies on ion sorption property and stability of YBa2Cu3O7−x in aqueous and mixed solvent media

Abstract

Abstract Ion sorption behaviour and stability of YBa 2 Cu 3 O 7−x in water and methanol-water mixture was studied by chemical analyses of the solutions and oxide and X-ray analyses of the oxide after treatment. Ba is preferentially leached from YBa 2 Cu 3 O 7−x by water,whereas in methanol-water mixture leaching of Ba is considerably reduced. The 1-2-3 phase of YBaCuO could not be stabilised by increasing the concentration of methanol in methanol-water mixture. In presence of dissolved NaCl and CaCl 2 in 20 v% methanol-water mixture, the leaching of Ba was further reduced and the residual solid contained mainly the 1-2-3 phase of YBaCuO. It was possible to incorporate Ca into the YBa 2 Cu 3 O 7−x matrix using CaCl 2 dissolved in 20 v% methanol-water mixture. The consequences of treating YBa 2 Cu 3 O 7−x with solutions of salts dissolved in methanol-water mixture on its superconducting property are discussed.