Exploration of Interaction Dynamics between Au-doped Graphene and Aliphatic-Aromatic VOCs

This study aims to examine the electro-chemical properties of toxic VOCs found in industrial effluents viz. ethylene, acetylene, and benzene, and their sensitivity and reactivity towards gold (Au) doped graphene sheet (Au-G). Several electro-chemical properties were evaluated to determine the sensing capabilities, which included the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), molecular electrostatic potential (MEP), partial density of states (PDOS), band structure, and infrared (IR) spectra for three different cases. Molecular orbital energy gap, MEP, and band structure supported strong reactivity characteristics of benzene and ethylene over Au-G as compared to acetylene. The adsorption characteristics of these gases were analyzed via adsorption energies which was found to be -1.01 eV for ethylene, -0.68 eV for acetylene, and -1.21 eV for benzene, respectively. The findings were further validated by binding distance analysis, electron localization function (ELF) mapping and Mulliken charge analysis. This study also highlights the potential of Au-doped graphene as a gas sensor for detecting these toxic VOCs which have significant environmental and health implications.