Theoretical investigation of CO adsorption on TM-doped (MgO)12 (TM = Ni, Pd, Pt) nanotubes

CO adsorption on TM-doped magnesia nanotubes (TM = Ni, Pd and Pt) have been studied by using density functional theory. Our calculation results show that CO favors adsorption on TM-doped magnesia nanotubes in the form of C atom bonding with TM atom. Fukui indices analysis clearly exhibits that doping of impurity TM atom allows for a noticeably enhancement of nucleophilic reactivity ability of magnesia nanotube. The adsorption energies demonstrate that CO molecule is more strongly bound on the 3-fold TM atoms than the 4-fold TM atoms. This finding is well confirmed by TM-C bond length, charge transfer and C-O vibrational frequency. The high adsorption energy of 2.55 eV is found when CO adsorbs on 3-fold Pt in Pt-doped magnesia nanotubes, implying the kind of the doping TM atom has a significant influence on the chemical reactivity. (C) 2011 Elsevier B. V. All rights reserved.