Computational study of B- or N-doped single-walled carbon nanotubes as NH3 and NO2 sensors

Abstract The adsorption of NH 3 and NO 2 in B- or N-doped (10, 0) single-walled carbon nanotubes (SWCNTs) was investigated by using density functional computations to exploit their potential applications as gas sensors. NH 3 can be chemisorbed only in B-doped SWCNTs with apparent charge transfer, so B-doped SWCNTs can be used as NH 3 sensors. Both B- and N-doping make NO 2 chemisorption feasible in SWCNTs, but the binding of NO 2 with B is too strong, indicating an impractical recovery time as gas sensors. Due to the medium (optimal) adsorption energy and the conductance reduction accompanied with the charge transfer between SWCNTs and gas molecules, N-doped SWCNTs are potentially good NO 2 sensors.