Synthesis and enhanced acetone sensing properties of 3D porous flower-like SnO2 nanostructures

The three-dimensional (3D) hierarchical SnO2 nanoflowers constructed by two-dimensional (2D) porous nanosheets were successfully fabricated by a one-step hydrothermal method and calcination procedure. The nanostructure and morphology of the hierarchical flower-like SnO2 were characterized by X-ray diffraction (XRD), energy dispersive X-ray detector (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. A possible formation process and growth mechanism for such fabricated 3D hierarchical SnO2 nanostructures have been proposed based on the experimental results. It is found that the flower-like SnO2 architectures were composed of many 2D porous nanosheets with the thickness about 20 nm. In addition, the gas sensor based on this 3D hierarchical structure has an optimum operating temperature of 280 degrees C, high sensitivity, quick response/recovery time and good selectivity for acetone. (C) 2014 Elsevier B.V. All rights reserved.