Synthesis of superconducting Ba1-xKxBiO3 by a modified molten salt process

A modified molten salt process has been developed to directly synthesise th e superconducting Ba1-xKxBiO3. Unlike the other known synthetic procedures in which either the multiple steps are necessary (ceramic method) or the ch emical composition and the superconducting properties may depend on various factors (electrolytic method), this process offers several advantages such as low temperature synthesis, single-step reaction as well as easy control of stoichiometry. The superconducting transition temperature of the so-pre pared sample with x = 0.4 reaches 30.8 K, among the highest reported in thi s system. Further. this process may, potentially, be extended to the other related systems. (C) 2001 Elsevier Science Ltd. All rights reserved.