Influence of Ag particle size on ethanol sensing of SnO1.8:Ag nanoparticle films:: A method to develop parts per billion level gas sensors

The influence of Ag particle size on ethanol sensing of SnO1.8:Ag films composed of size-selected nanoparticles with independently controlled size and concentration of Ag is reported in the present study. The study shows that Ag nanoparticles are acting as catalyst for chemical sensitization through a spillover effect. The catalyst particles are observed to be more active on decreasing their size, resulting into an improved sensor response. A response time of 2 s for 1000 ppm ethanol has been achieved. Detection of 100 ppb ethanol in air has been demonstrated using this well-defined technique. (c) 2006 American Institute of Physics.