In this work we investigate the detection performance of nanofibers of tin oxide (SnO2) towards sub-0.1 ppm nitrogen oxide (NO2) and ozone (O3) in air. It is found that SnO2 nanofibers are more sensitive to O3 than to NO2. and the optimal working temperature differs significantly between the two gases: 200 ºC (NO2) and 350 ºC (O3). SnO2 nanofibers loaded with reduced graphene oxide (rGO) show higher sensitivity than nanofibers of pure SnO2 at low temperatures and the optimal working temperature diminishes by around 150 ºC for the two gases. The air humidity does not modify the optimum working temperature of rGO-loaded SnO2 nanofibers but it affects their sensitivity at temperatures below 150 ºC. Irradiation with UV light is a promising method to activate gas desorption from rGO-loaded SnO2 nanofibers so that this material could be used in chemiresistive sensors for low temperature detection of air pollutants.
Acknowledgements
The Interreg-Sudoe Programme of the European Union (EU) is acknowledged for funding this research (Grant Agreement SEO2/P1/E569, NanoSen-AQM, www.nanosenaqm.eu).
