Ethyl benzene detection by BN nanotube: DFT studies

Electrical sensitivity of a boron nitride nanotube (BNNT) was examined toward ethyl benzene (C8H10) molecule by using density functional theory (DFT) calculations at the B3LYP/6-31G(d) level, and it was found that the adsorption energy (Ead) of ethyl benzene on the pristine nanotubes is about −11.42 kJ/mol. But when nanotubes have been doped with Si, O, S. P atoms, the adsorption energy (Ead) and recovery time changed and the sensitivity of the nanotubes as adsorbent of C8H10 molecule was increased. Calculations showed that when the nanotube is doping, the adsorption energy will be equal to −1.75 kJ/mol which leads to a decrease in the recovery time and also, due to doping the nanotube with O, the amount of HOMO/LUMO energy gap (Eg) will reduce significantly. It seems that nanotube (BNNT) is a suitable semiconductor after doping, and the doped BNNT in the presence of ethyl benzene an electrical signal is generating directly and therefore can potentially be used for ethyl benzene sensors, but BNNT is not a suitable adsorbent for C8H10 molecules.