Electrospinning of superconducting YBCO nanowires

YBa₂Cu₃O_7−δ (YBCO) nanowires with critical transition temperature T_c = 91.7 K were synthesized by an electrospinning process with the use of sol–gel precursors. A homogeneous polymeric solution containing Y, Ba, and Cu acetates was electrospun, resulting in collections of randomly oriented nanowires as well as bundles of aligned nanowires. Fully crystallized YBCO nanowires were obtained after calcination at temperatures as low as 820 °C. The morphology, microstructure, and crystal structure were investigated, and the diameters of the polycrystalline nanowires varied between 120 and 550 nm depending on the viscosity of the precursors. Thinner individual wires, with diameters in the 50–80 nm range, were synthesized with a single grain structure across the entire wire cross-section. (paper)