Unravelling the interaction between boron nitride nanosheets and organic pesticides through density functional theory studies

Abstract

In recent years, the concerns over the contamination of water resources due to pesticides and their residues have risen. To address this issue, the present study investigates the adsorption of some commonly used pesticides (acetamiprid, clothianidin, imidacloprid, thiacloprid and tri-allate) on monolayer boron nitride nanosheets (BNNs) from wastewater based on the first-principle density functional theory. A standard B3LYP model and 6-311G basis set were used to obtain the electrostatic potential maps, the density of states plot and HOMO-LUMO energy distributions. The feasibility of adsorption was confirmed from the adsorption energy calculations. The recovery time values were evaluated to examine the recovery of BNNs sheets after the adsorption. The electrostatic potential maps examined the local electron density distribution over the pesticides before and after adsorption. Quantum mechanical descriptors were evaluated to understand the chemical activity of the species involved in the process. The HOMO-LUMO distribution and DOS plots indicated that HOMOs of pesticides play an important role in the interactions. The quantum descriptors indicated weak interactions between pesticides and BNNs. The RDG and NCI plots confirmed the dominance of Van der Waals forces during adsorption interactions and showed that the forces operate to a greater extent during adsorption of imidacloprid.