Computational Study on Adsorption Characteristics of Phenol and Guaiacol Over Single and Multiple Nitrogen-Doped Graphene

摘要

The experimental synthesis of nitrogen-doped graphene (N-doped graphene) has opened the door for its application in many catalytically important processes. In this study, the authors report the properties of N-doped graphene, like the electron density distribution, charge distribution, electrostatic potential, etc. Subsequently, the adsorption characteristics such as the charge transfer, adsorption energy, dipole moment change, etc., are presented for the bio-oil model compounds (phenol and guaiacol) to realize the potential of N-doped graphene in bio-oil deoxygenation. The density functional theory (DFT) method is employed for calculating all the aforementioned properties. It is found that doping with nitrogen significantly alters the electronic properties of graphene favourably. For strong adsorption, either a high charge transfer between the catalyst and the model compound and/or a strong delocalization of the charge on the surface is desired. Both phenol and guaiacol show similar adsorption energy on non-defective and defective N-doped graphene; and increasing the doping does not increase the adsorption energy on the surface.