Fig. shows the gas sensing response of the tin-dichalcogenide sensor devices for working temperatures between 30 °C and 300 °C, when exposed to synthetic air at several NO2 concentrations. We observed that the electrical resistance steeply increases just after the oxidizing gas is released into the system, displaying a typical n-type semiconducting behavior . This particular behavior takes place due to the adsorption and desorption rates on material's surface, which is proportional to the gas concentration. The synthetic air and NO2 exposure cycles exhibit a reversible adsorption/desorption process for all concentrations as the working temperature increases. It is important to note, however, that up to 5 ppm NO2 concentrations, the adsorption and desorption process is completely reversible for Sn(S0.5Se0.5)2 and SnSe2, and partially for SnS2, even at low temperatures, such as 50 °C. This outcome demonstrates the capabilities of these materials as good candidates for NO2 detection at room temperature.