Computational Modeling and Analysis of a Chemical Gas Sensor Utilizing WO 3 Thin Films for NO 2 Detection

In this study, we have proposed and analyzed a theoretical model for NO 2 gas sensors. We have developed a realistic model for variation in sensor response as a function of the gas concentration, temperature, humidity, and sensing film thickness and derived a general expression relating to the sensor response. Tungsten trioxide (WO 3 )-based gas sensors were adopted because of their physical and chemical properties, low cost, and ease of preparation. Superior sensing characteristics were obtained for 0.42 eV activation energy, where the device exhibited a sensor response of 14.41 toward 1 ppm NO 2 gas concentration at room temperature. To validate the applicability of the proposed model, a comparative analysis was conducted, and an excellent match was obtained between the proposed model and experimental data. The analysis carried out in this work offers a feasible and promising approach for a wide variety of sensing materials.