A Comparative Study of Graphynes for Sensing of Gasses (SO₂ & Acetylene) Using DFT Calculations and MD Simulations

One of the principal industrial pollutants, SO₂ gas is a primary byproduct of the burning of fossil fuels and greenhouse gases. Further, acetylene (C₂H₂) is a colorless, volatile, and toxic gas that is used in dissolved gas analysis. Therefore, carbon allotropes can provide a low-cost and effective method for its detection and removal. A theoretical investigation of the graphyne with SO₂ and acetylene have been done using density functional theory (DFT) computations. The physiochemical and thermodynamic properties of carboneceous materials have been analyzed with SO₂ and acetylene of ranging polarity to find out the best allotrope with stable interactions. Further, the optimized geometries were investigated for the adsorption of both the gases. To investigate the changes in interactions, the feasibility of adsorption by the allotropes as the gas molecule changes was performed by varying the carbon chain. The study was done by analyzing the interactions, thermodynamic properties obtained from DFT. The different interactions (hydrogen bonding, electrostatic, van der Waal, steric effects) formed are studied using non-covalent interactions (NCI) & electron localized function (ELF) also with density of states (DOS) spectra. Molecular dynamics (MD) simulations of the allotropes with these gases was performed to analyze the stability of the interaction by analyzing the root mean square deviation (RMSD) and root mean square fluctuation (RMSF) plots.