Gas sensing characteristics of WO3 nanoplates prepared by acidification method

• Published in: Thin solid films 2011-01, Vol.519 (6), p.2020-2024
• Main Authors: Kim, Sun-Jung, Hwang, In-Sung, Choi, Joong-Ki, Lee, Jong-Heun
• Format: Article
• Language: English
• Subjects: Acidification; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Gas sensor; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Materials science; Methods of nanofabrication; Morphology; Nanocomposites; Nanomaterials; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanostructures; Nitrogen dioxide; Other topics in nanoscale materials and structures; Physics; Powders; Scanning electron microscopy; Selective detection; Selectivity; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Tungsten oxide; Tungsten oxides; X-ray diffraction
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.10.026

WO3⋅H2O nanoplates were prepared by the acidification of Na2WO4∙2H2O and converted into monoclinic WO3 nanoplates by heat treatment. The sizes, morphologies and preferred orientation of the WO3 nanoplates could be controlled by manipulating the acidity of the solution used for the acidification reaction. All of the WO3 nanoplates showed the selective detection of NO2 in the presence of other reducing gases, such as C2H5OH, CH3COCH3, CO, C3H8, and H2. The gas response, selectivity, and response speed were optimized by varying the morphology of the sensing materials and operation temperature. The WO3 nanoplates with a mean edge size of 192nm showed the most rapid gas response along with a high response and selectivity to NO2 when operated at 300°C.