The role of grain size in response of Sno 2- and In 2o 3-based conductometric gas sensors

Abstract

Basing on the experimental results, obtained while studying both structural and gas sensing properties of the SnO2 and In2O3 films deposited by spray pyrolysis method, it was analyzed the influence of the crystallites size on the response of the SnO2- and In2O3-based thin film gas sensors. It was confirmed that that the grain size is one of the most important parameters of metal oxides, controlling almost all operating characteristics of the solid state gas sensors. However, it was shown that the decrease of the grain size is not a universal decision contributing to the improvement of sensor response. The decrease of the grain size could be accompanied either by the improvement, or the worsening of gas sensor operating characteristics. © (2012) Trans Tech Publications, Switzerland.