YBCO OXALATE COPRECIPITATION IN ALCOHOLIC SOLUTIONS

A process for synthesis of ultrafine YBa2Cu3O7-x powder by oxalate cop recipitation from nearly saturated solutions of the metal acetates and a 2-propanol solution of oxalic acid was developed. The coprecipitati on was complete within 5 min in an ice bath at 0-2-degrees-C. The fina l stoichiometry was Y:Ba:Cu = 1:1.994:2.991, while the particle size a nd surface area in the homogeneous coprecipitated powder were 0.1-0.2 mum and 24.9 m2.g-1, respectively. Because of the uniformity and parti cle size of the coprecipitated material, reactive YBCO powder with a s urface area of 1.7 m2.g-1 can be obtained at 780-degrees-C in about 12 h.