First principles modeling of boron-doped carbon nanotube sensors

作者：Talla Jamal A^*

来源：Physica B: Condensed Matter , 2012, 407(6): 966-970.

DOI：10.1016/j.physb.2011.12.120

• Doping
• Single-walled carbon nanotubes
• Ab initio
• ABINIT
• Simulation
• Density of states
• Gas sensors

We investigated the interactions between two different geometrical configurations of single-walled carbon nanotubes and boron atoms using first-principle calculations within the framework of the density functional theory. With the aid of ab initio calculations, we introduced a new type of toxic gas sensor that can detect the presence of CO, NO and H-2 molecules. We proved that the dopant concentration on the surface of the nanotube plays a crucial role in the sensitivity of this device. Furthermore, we showed that small concentrations of dopants can modify the transport and electronic properties of the single-walled carbon nanotube and can lend metallic properties to the nanotube. Band-gap narrowing occurs when the nanotube is doped with boron atoms. The emerged new energy level near the Fermi level upon boron doping clearly indicates the coupling between the p orbital of the boron atom and the large p bond of the carbon nanotube. We also predicted a weak hybridization between the boron atoms and the nanotube for the valence-band edge states; this weak coupling leads to conducting states around the band gap.

• 出版日期2012-3-15