THE SOL-GEL ROUTE TO SUPERCONDUCTORS

The preparation of the high-T-c oxide superconductors by the sol-gel process has led to materials that are usually single-phase and more homogeneous than those prepared by the conventional solid-state reaction route. The synthesis is carried out at relatively low temperatures and shorter periods of heating are required. The materials have small particle size. By this method built materials, thin and thick films, wires, tapes and fibers have been prepared and their physical properties were usually found to be improved. The review is devoted to the metal cuprate superconductors, especially to electron deficient ones and to a minor extent to electron excess materials.