Mesoporous WO3 modified by Au nanoparticles for enhanced trimethylamine gas sensing properties

In this paper, KIT-6 is used as a template to prepare ordered mesoporous material WO3 and Au-loaded WO3 (Au-WO3) with excellent crystallinity. Sensors based on mesoporous WO3 and Au-WO3 are fabricated for detection of 19 important gases, including trimethylamine, formaldehyde and CS2 gases. The results show that the Au-WO3 sensor has better selectivity and higher sensitivity to TMA. At the working temperature of 268 °C, the response (Ra/Rg) of the Au-WO3 sensor to 100 ppm TMA is 41.56 and the response time is 1 s. In addition, the sensor has excellent response/recovery capabilities and stability. These high sensing performances mainly attribute to the electronic and chemical sensitization of the noble metal Au and the presence of high surface area supported by the mesoporous structure. Therefore, the Au-doped mesoporous WO3 should be a promising material for high performance TMA gas sensor.