Theoretical Study of Binding of Metal-Doped Graphene Sheet and Carbon Nanotubes with Dioxin

摘要

Using density functional theory,we have theoretically studied dioxin binding on a graphene sheet or carbon nanotubes(CNT),finding that they can be effective adsorbents for dioxin in the presence of calcium atoms.This is due to a cooperative formation of sandwich complexes of graphene sheet or(5,5)CNT through the interaction pi-Ca-pi with the total binding energy of more than eV.This correlates with the band structure analysis,which indicates charge transfer from the carbon systems and calcium atoms to dioxin when the molecule binds to the metal-doped carbon systems.For CNT with small radii,the relative strength of CNT-dioxin interaction is dependent on their chiralities.Upon dioxin binding,a large increase in the electronic density of states near the Fermi level also suggests that they can be used for dioxin sensing.Fe-doped CNT is also found to bind dioxin strongly,revealing an important role played by remnants of metallic catalysts in the chemical properties of CNT.