Enhanced response of WO3 thin film through Ag loading towards room temperature hydrogen gas sensor
Ramya Barathy T, P.V. Karthik Yadav, Anibrata Mondal, Karthickraja Ramakrishnan, J. Jayaramudu, Chunli Liu, Y. Ashok Kumar Reddy
Abstract
This study investigates the enhancement of hydrogen gas-sensing performance by introducing silver (Ag) nanoparticles onto tungsten trioxide (WO 3 ) thin films . Herein, the WO 3 thin films are deposited onto SiO 2 /Si substrates using a sputtering technique and Ag nanoparticles are loaded onto the WO 3 surface through a spin coating technique . To evaluate the sensing performance of a hydrogen gas, interdigitated titanium (Ti) electrodes are deposited onto the Ag:WO 3 layer. Structural, chemical, and morphological analyses are conducted for both pristine WO 3 and Ag:WO 3 thin films, followed by the investigation of gas-sensing performance by varying hydrogen gas concentrations from 100 ppm to 300 ppm and operating temperatures between 30 °C and 300 °C. The obtained results demonstrate that Ag:WO 3 thin films exhibit a notably enhanced response of 5.08% when exposed to a concentration of 100 ppm of hydrogen gas at room temperature, compared to the pristine WO 3 of 3.40%. The fabricated Ag:WO 3 sensor exhibits a response time of 3.0 s, a recovery time of 4.5 s, and also demonstrates excellent stability over 45 days period. Finally, with the superior sensitivity and fast response time, the fabricated Ti/Ag:WO 3 /Ti hydrogen gas sensor test-device can be a potential for improvement of safety from both industrial and environmental perspectives.