Photoluminescence Study of Defects in ZnO-Coated Polyacrylonitrile Nanofibers

Core-Shell nanostructures of one-dimensional (1D) polyacrylonitrile (PAN)/zinc oxide (ZnO) were obtained by combining atomic layer deposition (ALD) and electrospinning. Nanofibers with different ZnO thicknesses were synthesized and investigated. The present work offers novel information about 1D ZnO structural defects and activation energies (E_a) by performing photoluminescence (PL) measurements. PL measurements of 1D ZnO/PAN samples were investigated from 77 to 273 K (room temperature). By analyzing the obtained data of the emission spectrum, E_a and temperature coefficients were calculated. The results let us suggest an approximate model of defects in 1D ZnO/PAN structures. It was observed that optical properties are strongly related to the structural properties of the obtained 1D materials; that is, the calculation of the concentration of defects in the ZnO layer was done by analyzing the optical measurements. These investigations allow prediction of the properties of the materials and open a new roadmap for reliable sensing.