Nano Ag-Doped In2O3 Thick Film: A Low-Temperature H2S Gas Sensor. (23rd October 2011)

• Record Type: Journal Article
• Authors: Chavan, D. N.; Patil, G. E.; Kajale, D. D.; Gaikwad, V. B.; Khanna, P. K.; Jain, G. H.
• Other Names: Siciliano P. Academic Editor.
• Is Part Of: Journal of sensors. Volume 2011(2011)
• Publication Date: 2011-10-23
• Subjects: Detectors -- Periodicals; 681.205
• DOI: 10.1155/2011/824215
• Languages: English
• ISSNs: 1687-725X

Abstract

Abstract : Thick films of AR grade In2 O3 were prepared by standard screen-printing technique. The gas sensing performances of thick films were tested for various gases. It showed maximum sensitivity to ethanol vapour at 350°C for 80 ppm concentration. To improve the sensitivity and selectivity of the film towards a particular gas, In2 O3 sensors were surface-modified by dipping them in a solution of 2% nanosilver for different intervals of time. Obtained results indicated that spherical nano-Ag grains are highly dispersed on the surface of In2 O3 sensor. The surface area of the nano-Ag/ In2 O3 sensor is several times larger than that of pure In2 O3 sensor. In comparison with pure In2 O3 sensor, all of the nano-Ag-doped sensors showed better sensing performance in respect of response, selectivity, and optimum operating temperature. The surface-modified (30 min) In2 O3 sensor showed larger sensitivity to H2 S gas (10 ppm) at 100°C. Nano silver on the surface of the film shifts the reactivity of film from ethanol vapour to H2 S gas. A systematic study of gas sensing performance of the sensor indicates the key role played by the nano silver species on the surface. The sensitivity, selectivity, response, and recovery time of the sensor were measured and presented.