Superior Selectivity and Sensitivity of C3N Sensor in Probing Toxic Gases NO2 and SO2

The adsorption of gas molecules, such as N-2, O-2, CO2, H2O, CO, NO, NO2, H2S, NH3, and SO2 on monolayer C3N has been investigated by means of first-principles and non-equilibriumGreen's function calculations. We show that monolayer C3N is preferable for the NO2 and SO2 molecules with suitable adsorption strength and apparent charge transfers. Moreover, the I-V characteristics of C3N show clear variations after the adsorption of NO2 and SO2. Such sensitivity and selectivity to NO2 and SO2 molecules make C3N a promising candidate for highly sensitive gas sensor.