Evaluating the sensitivity and selectivity of carbon nitride monolayer toward acetylene and ethylene explosive gases

Abstract

The demand for developing sensors capable of precisely and selectively identifying harmful substances such as fluorides and cyanides is steadily increasing. Within this piece of research, the detection capability of a carbon nitride nanosheet (referred to as C₃N₃NS) was investigated for the accurate identification of C₂H₄ and C₂H₂ through the implementation of a DFT methodology. The interaction energies of the most stable structures of C₂H₂ and C₂H₄ over C₃N₃NS were calculated at about −53.46 and – 21.92 kJ mol⁻¹, respectively. Based on the analysis of interaction energies, C₂H₂ formed a strong bond with C₃N₃NS, while C₂H₄ was adsorbed onto the C₃N₃NS through weak van der Waals forces. The complexation of C₂H₂ and C₂H₄ with C₃N₃NS was thoroughly examined using non-covalent interactions (NCIs), frontier molecular orbitals (FMOs), and natural bond orbital charge transfer (QNBOs). Significant differences in bandgap energy were observed in the FMO analysis for C₂H₂ with C₃N₃NS, ranging from 3.59 to 2.37 eV, highlighting the presence of strong non-covalent interactions (NCIs). Furthermore, the presence of non-covalent bonds between complexes was verified through the non-covalent interactions-low density gradient (NCI-RDG) analyses. The recovery time in the range for C₂H₂@C₃N₃NS and C₂H₄@C₃N₃NS was 5.71 × 10⁻⁵ s and 3.32 × 10⁻⁷ s, respectively. The significant specificity of the monolayers towards analytes and the potential of all discoveries can offer researchers practical recommendations for constructing highly sensitive sensors for C₂H₂ and C₂H₄ utilizing C₃N₃NS.