CO sensing properties of SnO2 thin films prepared by the sol-gel process

Undoped and Pd-doped SnO2-based thin film chemical sensors have been developed by means of the sol-gel technique. The prepared films were sensitive to CO gas as demonstrated by a change in electrical conductivity. The temperature dependence of the resistance change and response and recovery times have been measured. An improvement of the sensitivity and a lower operating temperature were observed in Pd-modified films. (C) 1997 Elsevier Science S.A