Polymer-assisted co-axial multi-layered circular ZnO nanodisks

Multi-layered ZnO circular nanodisks were efficiently fabricated using sodium dodecyl sulfate (SDS) and polyvinylpyrrolidone (PVP) polymer by a controlled hydrothermal method. As-prepared ZnO nanostructures were characterized by X-ray powder diffraction, field-emission scanning electron microscopy, and high-resolution transmission electron microscopy. The effect of SDS and PVP polymer on the formation of ZnO multi-layer nanostructures was described in detail. Based on experimental results, a possible mechanism of circular disk formation was proposed. The gas-sensing properties of multi-layered nanodisks were reported for formaldehyde under different concentrations from 5 to 1200 ppm at 300 degrees C A higher response toward formaldehyde was observed, rendering the multi-layered nanostructures a promising gas-sensing material for the on-site detection of formaldehyde. (C) 2015 Elsevier B.V. All rights reserved.