Synthesis of the high temperature superconductor YBa2Cu3O7-delta by the hydroxide co-precipitation method

Abstract

A new synthetic route is developed to prepare a hydroxide precursor for the superconductor YBa2Cu3O7-delta. In an inert atmosphere and at low temperature the yttrium, barium and copper hydroxides are co-precipitated by adding the metal perchlorates and sodium hydroxide together. The analysis of the precursor proved the absence of ClO4- and Na+ ions. The thermal treatment (12 h calcinating at 950 degrees C, 35 h sintering at 950 degrees C and 6 h annealing at 400 degrees C) gives a superconductor YBa2Cu3O7-delta with a transition temperature of 90.2 K.