Adsorption of V-series nerve agents on graphene oxide: spectroscopic validation, electronic properties and charge transfer dynamics

Abstract The adsorption of V-series nerve agents (VE, VG, VM, VX) on graphene oxide (GO) was systematically investigated using density functional theory (DFT) at the ωB97X-D/6-311G(d, p) level. Basis set superposition error (BSSE)-corrected adsorption energies reveal that physisorption governs the interaction, with the strongest binding observed for the GO Mid-COH/VG(O112) configuration at − 1.120 eV. The mid-sheet hydroxyl group consistently outperformed the terminal carboxyl group as the primary binding site. Validated theoretical IR and Raman spectra versus experimental ones accurately reproduced characteristic GO bands, and provided sage and reliable vibrational fingerprints for the V-agents, noting a P–S stretch shift from 617 cm⁻¹ (VG) to 521 cm⁻¹ (VX). Frontier molecular orbital analysis confirmed that the GO HOMO-LUMO gap remains stable (~ 5.1 eV), verifying non-covalent interactions. Population analysis identified V-agents as electron donors, where VX exhibited the highest charge transfer (ΔN = − 0.106) and lowest reorganization energy ( $${{\\uplambda}}_{hole}$$ = 0.651 eV) among the studied agents. Molecular electrostatic potential and Electron Localization Function analyses confirmed that hydrogen bonding at the P=O group drives the physisorption mechanism. Ultimately, the consistent adsorption behavior and pronounced dipole moment alterations establish GO as a theoretically promising platform for the capture and electrical detection of V series nerve agents, warranting further experimental investigation.