Influence of Pr content on the kinetics of Bi2Sr2CaCu2O8+δ phase formation

Reaction kinetics of high critical temperature superconductors (HTS) has been less studied than their superconducting properties. Usually, doped samples are prepared by solid-state reaction method from oxides and carbonate powders in the same sintering conditions as applied for non-doped samples. This fact has caused publication of different results in the literature about the solubility limit in HTS. Thus, in order to obtain more information about the influence of Pr on the Ca site of the Bi2Sr2CaCu2O8+delta (Bi2212) phase, we have studied in this work the kinetics of phase formation in the Bi2212 + Pr system. To investigate the phases formed during sintering at 820 degreesC, several samples of different Pr content were analyzed by X-ray powder diffractometry after various sintering durations (6-1500 h). We observed that increasing Pr content, the sintering time necessary to prepare single phase samples increases significantly at same temperature. (C) 2001 Elsevier Science B.V. All rights reserved.