Microstructure and Superconductivity of La_1.85Sr_0.15CuO₄ Nanowire Arrays

Abstract

Abstract Superconducting La 1.85 Sr 0.15 CuO 4 nanowire arrays are successfully synthesized through a sol–gel method combined with porous alumina as a morphology‐directing hard template for the first time. The morphology, structure, and composition of the as‐prepared nanowire arrays are characterized by field‐emission scanning electron microscopy, transmission electron microscopy, high‐resolution transmission electron microscopy, X‐ray diffraction, and energy‐dispersive X‐ray spectroscopy. These experimental results indicate that the nanowires are well crystallized with an approximately uniform diameter of about 30 nm. The superconducting transition temperature T c (ca. 30 K) of the annealed nanowires is lower than that in bulk La 1.85 Sr 0.15 CuO 4 . It is suggested that this superconductivity suppression is derived from the weakening of in‐plane hybridization in the nanowire system.