Novel bimodal ZnO (amorphous)/ZnO NPs (crystalline) electrospun 1D nanostructure and their optical characteristic

Abstract The aim of presented study were to produce amorphous ZnO nanowires filler by crystalline ZnO nanoparticles via the electrospinning process from a polyvinylpyrrolidone (PVP)/zinc nitrate (Zn(NO 3 ) 2 /dimethylformamide (DMF) and ethanol (EtOH) solution. The as obtained nanofibers were calcined at temperatures ranging from 400 to 600 °C to remove the organic phase. The 1D bimodal ZnO NWs were studied using a scanning and a transmission electron microscope (SEM, TEM) to analyse the morphology and structure of obtained materials. In order to examine the chemical structure of nanowires, the energy dispersive spectrometry (EDX) was used. Besides, a thermogravimetric analysis (TGA) was performed to show the polymer concentration loss in a function of temperature in order to obtain pure zinc oxide nanowires. The optical property analysis was performed on the basis of UV–Vis spectra of absorbance as a function of the wavelength. Using the modified Swanepoel method, which the authors proposed, and the recorded absorbance spectra determined the banded refractive index n, real n' and imaginary k part of the refractive index as a function of the wavelength, complex dielectric permeability e, real and imaginary part er and ei of the dielectric permeability as a function of the radiation energy of the produced ZnO nanowires.