Exploring the NH3 gas sensing efficiency of polyvinylpyrrolidone based tungsten trioxide (PVP/WO3) Nanocomposites: A recent progression in the toxic gas sensing materials

In this paper, a room temperature operable, highly reproducible, stable and selective ammonia gas sensor of PVP, WO3, and PVP/WO3 nanocomposites were investigated. Drop casting method was used to deposit the sensing materials on interdigitated copper electrode. Chemical reduction and ultrasonication methods were adopted for the preparation of WO3 and PVP/WO3 nanocomposites, respectively. The as-produced sensing materials were characterized by using FTIR, XRD, and SEM techniques. LCR meter was used to analyze the gas sensing properties of PVP, WO3 and PVP/WO3 (5-25 wt%) nanocomposites. Under same condition of temperature (300 K), humidity (40%RH), and NH3 vapors (100 ppm) the sensor based on PVP/WO3 20 wt% showed higher sensing response of 87.26 as compared to pure PVP and WO3 nanosheets sensor which was 15.36 and 3.37, respectively. The PVP/WO3 20 wt% based sensor exhibited excellent results in term of reproducibility, stability (90 days), response time (14 s), and recovery time (10 s).