Detection of volatile organic compounds using flexible gas sensing devices based on tungsten oxide nanostructures functionalized with Au and Pt nanoparticles

•Flexible gas sensing devices based on functionalized nanostructures are fabricated.•Functionalized nanostructures are integrated without the use of transfer methods.•The devices are sensitive to VOCs such as ethanol, methanol, acetone and toluene.•Pt-functionalized sensors suggest selectivity to ethanol and methanol.

Flexible gas sensor devices are fabricated and optimized by integrating directly, via a single-step vapor-phase deposition method, highly crystalline tungsten oxide nanostructures functionalized with either gold or platinum nanoparticles. Gas tests of these devices show significant improvements with respect to flexible gas sensors based on non-functionalized structures, including greater responses to various volatile organic compounds (ethanol, acetone, methanol and toluene) and better selectivity towards ethanol and methanol, as demonstrate results for the sensors based on platinum-functionalized structures. The method presented here, which includes the fabrication of the whole flexible gas sensing device and the integration of functional nanostructures without the use of transfer methods, provides a simpler, faster and inexpensive method for the fabrication of highly functional flexible microsystems for gas sensing.

Graphical abstractFlexible gas sensor devices based on highly crystalline tungsten oxide nanostructures, functionalized with Au or Pt nanoparticles, are fabricated and used for the detection of various volatile organic compounds (ethanol, acetone, methanol and toluene). Results demonstrate enhanced selectivity to similar concentrations of ethanol and methanol when using platinum-functionalized sensors.Figure optionsDownload full-size imageDownload as PowerPoint slide