Two-dimensional carbon nitride (C3N) nanosheets as promising materials for H2S and NH3 elimination: A computational approach

Motivated by the increased emission of pollutant in the atmosphere, we explore the promise of pristine and defect carbon nitride (C3N) monolayers for H2S and NH3 capture by means of van der Waals corrected density functional theory (DFT) calculation. Our results reveal that the adsorption energies (E-b) of pristine C3N towards H2S and NH3 are 0.610 eV and 0.444 eV, respectively. However, a spontaneous partial dissociation of H2S is observed in case of single C and N vacancy in C3N monolayer with minimum E-b values of 1.90 and 1.577 eV, respectively. Furthermore, by using transition states (TS) calculation, we predicted a complete dissociation path of H2S by ab-initio molecular dynamics simulation at 1000 K. Results show complete dissociation of H2S molecule on C3N-C system. In addition, the trend of our results has demonstrated that O-2 and H2O contaminations in our sample could barrier H2S adsorption. However, we also observed a physisorption phenomenon in the case of the interaction between NH3 and C3N. In addition, the binding energy of NH3 at C and N vacancies resulted in Eb values of 0.45 and 0.30 eV, respectively. This proves that the mono vacancy defect is highly selective toward H2S gas than NH3. This study reveals a future for Two-Dimensional C3N nanosheets as H2S sensor.