Fabrication of a SnO2 nanowire gas sensor and sensor performance for hydrogen

SnO2 nanowire gas sensors have been fabricated on Cd-Au comb-shaped interdigitating electrodes using thermal evaporation of the mixed powders of SnO2 and active carbon. The self-assembly grown sensors have excellent performance in sensor response to hydrogen concentration in the range of 10 to 1000 ppm. This high response is attributed to the large portion of undercoordinated atoms on the surface of the SnO2 nanowires. The influence of the Debye length of the nanowires and the gap between electrodes in the gas sensor response is examined and discussed.