Moon, Hi Gyu Jang, Ho Won Kim, Jin-Sang Park, Hyung-Ho Yoon, Seok-Jin 2024-01-20T18:03:45Z 2024-01-20T18:03:45Z 2021-09-05 2010-12 1738-8090 https://pubs.kist.re.kr/handle/201004/130888 We investigate the mechanism of the sensitivity enhancement in TiO2 hollow-hemisphere gas sensors. Using monolayer close-packed polystyrene microspheres as a sacrificial template, a TiO2 thin film based on a network of ordered hollow hemispheres is formed by room-temperature sputtering deposition and subsequent calcination at 550 degrees C. A thin film gas sensor based on the TiO2 hollow hemispheres exhibits a 225% change in its resistance when exposed to 50 ppm CO at 250 degrees C, whereas a gas sensor based on a flat TiO2 film shows an 85% change. Numerical analysis reveals that the enhancement of the gas sensitivity in the hollow-hemisphere gas sensor is simply the result of an increase in the effective surface area for the adsorption of gas molecules. English KOREAN INST METALS MATERIALS THIN-FILMS TITANIA Mechanism of the Sensitivity Enhancement in TiO2 Hollow-Hemisphere Gas Sensors Article 10.3365/eml.2010.12.135 1 ELECTRONIC MATERIALS LETTERS, v.6, no.4, pp.135 - 139 ELECTRONIC MATERIALS LETTERS 6 4 135 139 scie scopus kci other ART001505918 000286039600001 2-s2.0-78650986146 Materials Science, Multidisciplinary Materials Science Article THIN-FILMS TITANIA gas sensors TiO2 hollow hemispheres effective surface area CO