Highly sensitive and selective acetone sensor based on three-dimensional ordered WO3/Au nanocomposite with enhanced performance

With the development of medical science, analyzing the concentration of the volatile organic compounds (VOCs) in expiration has been considered as a rapid, convenient and noninvasive method for medical diagnosis. The detection of diabetes with acetone as a marker has received extensive attention, but the development of a highly sensitive acetone sensor remains various challenges to improve the sensing performance with nanostructure-controllable novel materials. In this work, an acetone sensor based on three-dimensional inverse opal (3DIO) tungsten oxide (WO3) composite modified with Au (WO3/Au) was obtained through a simple sacrificial template synthesis, which provided more active sites with macropore architecture. Moreover, with modification of Au nanoparticles (NPs), it is obvious that gas sensing property with "spillover effects" and catalytic action was obtained. The 3DIO WO3/Au gas sensor exhibited good selectivity to acetone, and showed great test performance from 100 ppb to 100 ppm. A corresponding actual detection limit of 100 ppb at 410 degrees C was realized, which could allow real-time and reliable diagnosis of diabetic by acetone monitoring. Furthermore, it also showed good stability and faster response and recovery times compared with pure WO3 sensors. The 3DIO WO3/Au gas sensor shows great potential in practical application of a noninvasive and more accurate monitoring and detection of diabetes.