Enhanced nitrobenzene sensing in metal anchored gamma-graphyne: predictions from density functional theory

Abstract

Nitrobenzene (NB), being a toxic industrial effluent, its adsorption performance on pristine and metals (Al, Cu and Sc) anchored 2D graphyne (GY) monolayer was studied systematically via the first principles DFT simulations. The NB was found to be weakly adsorbed on the pristine monolayer with an energy of −0.46 eV due to the long-range van der Waals interactions. The NB was strongly adsorbed on the anchored metal site except for the case of Cu. The adsorption energy calculations suggest that the Al-anchored GY monolayer is excellent for the NB sensing because of the reasonable adsorption energy of −1.18 eV, charge transfer of 0.57 e and attainable recovery time of 2.4 s at 450 K. The work function sensitivity of the Al anchored system towards the NB molecule is 10% higher than the pristine system. Moreover, the ab-initio molecular dynamics simulations have predicted the room temperature structural steadiness of the Al-anchored GY monolayer. Overall, our research suggests that the Al-anchored GY monolayer is promising to adsorb the NB molecules effectively and can be potentially applied as an excellent NB biomolecule sensor.