Boron- and Nitrogen-Doped Carbon Nanotubes with Surface Defects: An Ab Initio Study

We study the structural and electronic properties of nitrogen (N) and boron (B) doped carbon nanotubes in the presence of point surface defects. Our calculations are carried out using an ab initio density functional computational method. The equilibrium structures, electronic density of states, and the charge transfer of B- and N-doped carbon nanotubes are examined in the presence of Stone-Wales (SW) defects and vacancies. Our calculations show that B and N impurity atoms combined with point surface defects induce substantial structural changes in carbon nanotubes. We find that introducing a vacancy into B-/N-doped carbon nanotubes changes the spatial distribution of the neighbor atoms, particularly those located around the vacancy. Our study reveals that B and N impurity atoms combined with point surface defects have significant effects on the electronic structure of carbon nanotubes. These results suggest that impurity atoms with point surface defects can be used to modify the electronic properties and the surface reactivity of carbon nanotubes.