DFT study of adsorbing SO₂, NO₂, and NH₃ gases based on pristine and carbon-doped Al₂₄N₂₄ nanocages

The adsorption of SO₂, NO₂, and NH₃ toxic gases on Al₂₄N₂₄ and Al₂₄N₂₃C nanocages was investigated by using density functional theory (DFT) calculations. The adsorption energies, frontier orbitals, charge transfer using natural bonding orbital (NBO) analysis, dipole moment, the partial density of states (PDOS), thermodynamic relationships, non-covalent interaction (NCI), and quantum theory of atoms in molecules (QTAIM) were considered. The results reveal that carbon-doped Al₂₄N₂₄ nanocage increases the adsorption energies for SO₂ and NO₂ gases while decreasing the adsorption energy of NH₃ gas. The ΔG for all configurations were negative except the configurations A1 and G2 confirming the weak adsorption of these two complexes. In conclusion, Al₂₄N₂₄ and Al₂₄N₂₃C nanocages are in general promising adsorbents for the removal of SO₂, NO₂, and NH₃ toxic gases. The Al₂₄N₂₄ and Al₂₄N₂₃C nanocages are ideal electronic materials.