Low oxygen pressure synthesis of NdNiO3- δnanowires by electrospinning

Abstract

Synthesis of RNiO3 (R = rare earth) nanowires can be interesting as building blocks with potential applications in optoelectronic devices. Here, we describe the synthesis and characterization of NdNiO3-δ (NNO) nanowires produced by electrospinning technique via polymeric precursor solution at relatively low temperature and oxygen pressure. These NNO nanowires were characterized by x-ray diffraction (XRD), x-ray photodetection spectroscopy (XPS), Field Emission Scanning Electron Microscopy (Fe-SEM), Magnetization (M(T)) and electrical resistance (R(T)) measurements. SEM images revealed a granular nanowire microstructure of NNO nanostructures, with a distribution of nanowire diameters ranging from 50 to 150 nm. The NNO nanowires also exhibit granular characteristics with an average grain diameter of 40 nm. The x-ray diffraction patterns of the NNO nanowires indicated that these samples exhibited a high degree of crystallinity and their Bragg reflections can be indexed to an orthorhombic-distorted (Pbnm symmetry) perovskite structure. The crystalline structure seems to be slightly texturized in some Bragg directions and with a slightly strained crystallite. M(T) and R(T) measurement as a function of temperature curves show that these NNO samples present a metal-insulator (MI) transition close to TMI ∼198 K, which is usually observed in NNO thin films and bulk samples. The nanostructured shape and these experimental observations can be promising in designing new electronic devices using this strongly correlated oxide.