Structural and Electronic Properties of Carbon Nanotubes and Graphenes Functionalized with Cyclopentadienyl–Transition Metal Complexes: A DFT Study

In order to explore possible ways of using metallocene compounds in heterogeneous catalysis and in sensor applications, we present a theoretical characterization of cyclopentadienyl (Cp) + transition metal (TM) complexes adsorbed on boron-doped carbon nanotubes (B-CNTs) and boron-doped graphenes. Using spin-polarized density functional theory calculations, we present a systematic study of the geometries, energetics, and electronic properties of CpTM (where TM = Fe, Ni, Co, Cr, Cu) adsorbed on both pristine and boron-doped carbon supports. Our work reveals significant increases of the binding energies between CpTM and boron-doped CNTs and graphenes (versus pristine carbon supports), surpassing even the adsorption strength of the isolated metals atoms (by about 2 eV). According to our electronic structure analysis, both the delocalization of the TM-d state by the presence of the Cp ring and the interactions between the Cp ring and the carbon substrate are responsible for the enhancement of the binding energ...