Theoretical study of the adsorption of substituted guaiacol and catechol radicals on a graphite surface

Adsorption of radicals obtained from catechol and guaiacol derivatives, on a graphite surface, was theoretically analyzed in the context of electrografting process. It was determined that the phenoxy type radicals preferred to link to the surface by aligning the oxygen (O·) radical on top of a carbon atom of the surface; also, it was found that the main contribution to the radical-surface stabilization, in the studied systems, comes from van der Waals interactions. In addition, the calculated free energies and overpotentials, related to the first oxidation process of catechol and guaiacol type of structures on the surface, provide insights about the behavior of these molecules and more complex derivatives of them in cyclic voltammetry experiments in glassy carbon electrode.