Pyrrole detection by BeO nanotube: DFT studies

Electrical sensitivity of a beryllium oxide nanotube (BeONT) was examined toward (C4H5N) molecule by using density functional theory (DFT) calculations at the B3LYP/6-31(d) level, and it was found that the adsorption energy (Ead) of pyrrole on the pristine nanotubes is   a bout -48.58kcal/mol. But when nanotubes has been doped with S and P atomes , the adsorption energy changed. Calculation showed that when the nanotube is doping by P, the adsorption energy is about -29.04kcal/mol and also the amount of HOMO/LUMO energy gap (Eg) will reduce significantly. Beryllium oxide nanotube is not suitable adsorbent for  pyrrole, but when the BeONT doped by P atom the amount of Eg was less than pristine BeONT and that is a suitable semiconductor.