A Highly Sensitive Ammonia (NH3) Sensor Based on a Tungsten Trioxide (WO3) Thin Film Decorated With Evaporated Platinum (Pt) Nanoparticles

An interesting ammonia (NH3) sensor based on a tungsten trioxide (WO3) thin film decorated with platinum (Pt) nanoparticles (NPs) is fabricated and demonstrated herein. Pt NPs are prepared by a rapid thermal evaporation (RTE) approach. The small size of these Pt NPs causes an increased surface area/volume (SA/V) ratio and enhanced sensing performance. The experimental results indicate good properties, including a higher sensing response of 72.61 under 1000 ppm NH3/air gas, a lower optimum operating temperature of 225 °C, and a lower detecting limit (≤1 ppm NH3/air). The studied device also has the advantages of a simple structure, easy fabrication, relatively low cost, a wide concentration detection range, and stable sensing performance. In addition, a first-order differential (FOD) and shape-preserving piecewise cubic interpolation (SPPCI) algorithms are employed to effectively reduce the redundant results and recover the reduced data for wireless transmission application. Thus, the studied Pt NP/WO3thin film-based device shows a promise for high-performance ammonia sensing applications.