Point-Defect Mediated Bonding of Pt Clusters on (5,5) Carbon Nanotubes

Abstract

The adhesion of various sizes of Pt clusters on the metallic (5,5) carbon nanotubes (CNTs) with and without the point defect has been investigated by means of density functional theory (DFT). The calculations show that the binding energies of Ptn (n = 1−6) clusters on the defect free CNTs are more than 2.0 eV. However, the binding energies are increased more than three times on the point defective CNTs. The dramatic increase of the binding energy has been further explained by the partial density of states, deformation charge density, and two population analyses methods (Mulliken and Hirshfeld). The stronger orbital hybridization between the Pt atom and the carbon atom shows larger charge transfers on the defective CNTs than on the defect free CNTs, which allows the strong interaction between Pt clusters and CNTs. On the basis of DFT calculations, CNTs with point defect can be used as the catalyst supports for noble metal nanoparticles adhesion, which can be applied to a series of catalytic reactions, such as fuel cell, hydrogenation, etc.