We perform the density functional theory (DFT) method to investigate the structural stability, the electronic structure, and the charge density distribution and transfer of the eight boron-doped (4, 0) single-walled carbon nanotube (B-doped SWCNT) systems. The eight B-doped (4, 0) SWCNT systems are distinguished by the number of B atoms substituting C atoms in a (4, 0) SWCNT structure. We find that all B-doped (4, 0) SWCNT structures are formed spontaneously marked by their negative formation energy. Also, all of these new systems have the stable structures. Then, surprisingly, we invent that the substitution doping B atoms retains the electronic properties of (4, 0) SWCNT. This is in contrast to other cases of impurities which alter the electronic properties of the doped structures. In addition, the distribution of charges between boron and carbon in the B-doped (4, 0) SWCNT structures indicates that there are electrostatic attractions between these two types of atoms. It shows that the presence of B atoms can be accepted by a defective (4, 0) SWCNT in order to establish a new integrated B-doped SWCNT structure.
Photovoltaic devices based on high density boron-doped single-walled carbon nanotube/n-Si heterojunctions
