Abstract:
In this work, the temperature dependent gas sensing properties of tin-doped zinc
oxide (ZnO:Sn) nanostructured films are investigated in detail. The two different contents
of Sn in ZnO:Sn samples (0.1 and 0.4 at% Sn) and rapid thermal annealing (RTA) at 725 ºC
were used, in order to find out the optimal conditions for the highest gas sensing
properties, i.e. higher gas response, selectivity and lowest operating temperature.
Generally, the Sn-doped ZnO nanostructured films showed high selectivity to volatile
organic compounds (VOCs) vapors, such as ethanol, acetone, 2-propanol and n-butanol,
compared to different reducing gases such as H2, NH3 and CH4. The optimal operating
temperature for all films is 250 – 300 ºC and the optimal content of Sn is 0.4 at%. The asgrown
films showed higher gas response compared to RTA treated ones. The gas sensing
mechanism was proposed and discussed in detail.