Enhancement and Optimization in Sensing Characteristics of Ammonia Gas Sensor Based on Light Assisted Nanostructured WO3 Thin Film

In this study, hydrothermally synthesized nanostructured WO
₃
thin film with interdigitated chromium electrode based ammonia gas sensor have been fabricated. The influence of different pH values for WO
₃
synthesis on structural, morphological, optical, and electrical were examined and reported. Sensor shows excellent response characteristics towards ammonia detection, even at lower gas concentration. The best sensing response have been obtained for WO
₃
nanostructure thin film at pH 2.25 with 250 °C operating temperature. For 5 PPM and 50 PPM NH
₃
gas concentration, sensor shows response 5.11 and 12.54 with 23/25 and 13/34 sec response/recovery time. It was also found that, enhancement in sensor response (7.32) with 21/25 sec response/recovery time (5 ppm) has been observed for blue light emission. The sensor has been tested for different period/interval of time and found that the proposed device is sensitive, reliable, inexpensive and eco-friendly for semiconductor applications.