First principle calculations of the chemisorption of SOx on doped carbon nanotubes and graphene

Abstract

We have carried out density-functional calculations to investigate the chemisorption of SO, SO2 and SO3 molecules on Al- and Si-doped carbon nanotubes with chiralities (5,5) and (9,0) and Al-doped graphene. Among several adsorption configurations studied, the most stable ones are those forming AlO or SiO bonds. SO2 adsorbs with smaller adsorption energies compared to SO and SO3. The adsorption is also accompanied by a change in the band gap energy; for the Al-doped CNT(9,0), the band gap energy drops by about 50% of its value. The adsorption energies for these gases on Al-doped graphene are comparable to those of the nanotubes.