First principles details into the grafting of aryl radicals onto the free-standing and borophene/Ag(1 1 1) surfaces

Abstract We suspect that a possible interaction of the aryl radicals with the borophene surface is important for the stabilization and functionalization of the surface. Therefore, the grafting of multiple para-substituted aryl radicals onto the borophene film is investigated using first-principles calculations based on density functional theory. The binding energy of the phenyl radicals on the borophene sheet, population analysis, and electron energy difference studies indicate a covalent nature of the bond between the B atom of the borophene and the C atom of the phenyl radical. Electron localization function analysis (ELF) is applied to estimate the nature of the bond between the borophene and the grafted phenyl moiety. The Mulliken charge population is used to evaluate the possible electron transfer at the bond-forming atoms (B and C) during this process. The obtained results helped to shed light on the grafting mechanism, activation energy, stabilization, and nature of the formed chemical bond between borophene and para-substituted phenyl moieties.