Enhanced sensing performances of networked SnO2 nanowires by surface modification with atmospheric pressure Ar–O2 plasma

Networked SnO2 nanowire sensors were fabricated on a basis of a selective growth technique. Subsequently, Ar–O2 plasma was applied in order to modify the nanowire surfaces. The NO2 sensing characteristics of the surface-modified SnO2 nanowires were compared to those of pristine SnO2 nanowires at an operating temperature of 300 °C. The results showed that the plasma treatment greatly enhanced the response as well as shortened the response and recovery times in SnO2 nanowire-based gas sensors. The enhancement is likely to result from an increase of active surface area for the adsorption of NO2 species by means of the plasma treatment.