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

The adsorption of gas molecules, such as N2, O2, CO2, H2O, CO, NO, NO2, H2S, NH3, and SO2on monolayer C3N has been investigated by means of first-principles and non-equilibrium Green's function calculations. We show that monolayer C3N is preferable for the NO2and SO2molecules with suitable adsorption strength and apparent charge transfers. Moreover, the I-V characteristics of C3N show clear variations after the adsorption of NO2and SO2. Such sensitivity and selectivity to NO2and SO2molecules make C3N a promising candidate for highly sensitive gas sensor.