Theoretical study of the para chlorophenol adsorption on phosphorus-doped polypyrrole with DFT

In this study, the adsorption of para-chlorophenol on phosphorus-doped polypyrrole was investigated using density functional theory (DFT). Calculations are performed at two levels b3lyp/6-31+G(d, p) and wb97xd/6-31+G(d, p), for two orientations of adsorbate molecules. The correlation-exchange function wb97xd shows more negative adsorption energy for the adsorption of these compounds. Evaluation of energy level changes of HOMO and LUMO orbitals, hardness, chemical potential, softness, electrophilicity, diploe moment, charge transfer by Molliken method and natural bond orbitals (NBO), adsorption energy, the density of states (DOS) diagrams, molecular electrostatic potential (MEP), Intermolecular distances and analysis of non-covalent interactions (NCI) have been performed. Analysis of non-covalent interactions shows more van der Waals interactions between adsorbent and adsorbate in the wb97xd correlation-exchange function compared to b3lyp.