Molecular Simulation of the Interaction of Diclofenac with Halogen (F, Cl, Br)-Encapsulated GaAs Nanoclusters.

Diclofenac is one of the most frequently consumed over-the-counter anti-inflammatory agents globally, and several reports have confirmed its global ubiquity in several environmental compartments. Therefore, the need to develop more efficient monitoring/sensing devices with high detection limits is still needed. Herein, quantum mechanical simulations using density functional theory (DFT) computations have been utilized to evaluate the nanosensing efficacy and probe the applicability of GaAs nanostructure and its engineered derivatives (halogen encapsulation F, Br, Cl) as efficient adsorbent/sensor materials for diclofenac. Based on the DFT computations, it was observed that diclofenac preferred to interact with the adsorbent material by assuming a flat orientation on the surface while interacting via its hydrogen atoms with the As atoms at the corner of the GaAs cage forming a polar covalent As-H bond. The adsorption energies were observed to be in the range of -17.26 to -24.79 kcal/mol and therefore suggested favorable adsorption with the surface. Nonetheless, considerable deformation was observed for the Br-encapsulated derivative, and therefore, its adsorption energy was observed to be positive. Additionally, encapsulation of the GaAs nanoclusters with halogens (F and Cl) enhanced the sensing attributes by causing a decrease in the energy gap of the nanocluster. And therefore, this suggests the feasibility of the studied materials as potentiometric sensor materials. These findings could offer some implications for the potential application of GaAs and their halogen-encapsulated derivatives for electronic technological applications.