Selective sensor based on covalent organic polyamide frameworks for the adsorption and detection of carcinogenic gases in aqueous phase using molecular simulationtle

Abstract

The emission of toxic gaseous pollutants such as nitrogen dioxide(NO₂), nitrogen trifluoride(NF₃), and hydrazine(N₂H₄) into the environment, particularly into water resources represents a serious and growing environmental challenge. In this study, covalent organic frameworks(COFs) were employed as intelligent adsorbents with tunable structures and inherent luminescent properties for the detection, adsorption, and removal of these three gaseous pollutants from the aqueous phase. By purposefully designing imine linkages and utilizing molecular dynamics(MD) simulations, the interactions of the target gases with the pore walls of the COFs were investigated and analyzed. The simulation results revealed that the interaction energies between the COFs and the pollutants for NF₃, N₂H₄, and NO₂ were −479.51, −57.10, and −10.79 kJ/mol, respectively, indicating a stronger interaction of COFs with NF₃ molecules. These findings confirm the crucial role of COF structural design in optimizing their performance for selective adsorption and sensing of toxic gases. Ultimately, these frameworks could serve as promising candidates for the development of environmental purification and monitoring technologies.