Fabrication of cuprate superconducting La1.85Sr0.15CuO4 nanofibers by electrospinning and subsequent calcination in oxygen

Abstract

The synthesis of high-temperature cuprate superconducting La_1.85Sr_0.15CuO₄ (LSCO) flute-like nanofibers (FNFs) viaelectrospinning and subsequent calcination in oxygen is reported. A reduced superconducting critical temperature was found to be around 19.2 K, a considerable decrease in comparison to its bulk counterpart (∼ 37 K). The weakened superconductivity in the LSCO FNFs is relevant to the following observations that (i) the presence of disorder or the amount of structural defects in the FNFs, (ii) the ab-plane dilatation (∼ 0.41%) and c-axis-compression (∼ 0.16%) distortions, leads to the reduced in-plane hybridization, and (iii) the suppression of A_1g Raman-active phonon mode ∼ 430 cm⁻¹ and enhancement of B_1g mode ∼ 370 cm⁻¹, is associated with the weakened electron–phonon coupling interaction. Our work demonstrates a “clean” high-yield nanofabrication of high-temperature cuprate superconducting materials.