Gamma-butyrolactone drug detection by Al-doped BC₃ nanotubes: A density functional theory study

Potential application of a pristine and Al-doped BC₃ nanotube (Al-BC₃NT) is explored in detection of gamma-butyrolactone (GBL) drug using DFT calculations. The GBL drug weakly adsorbed of the pristine BC₃NT with adsorption energy (E_ad) of -11.7 kcal/mol. The electronic properties of pristine BC₃NT were not altered sensibly by the GBL adsorption, indicating that this tube is not a sensor. By Al-doping in the structure of BC₃NT, the GBL interaction was strengthened (E_ad = -21.8 kcal/mol). The E_g of Al-BC₃NT dramatically declined from 2.38 to 1.93 eV, by GBL interaction. The electrical conductance of GBL/Al-BC₃NT was 681 times higher than that of the bare Al-BC₃NT. Thus, the Al-BC₃NT yields an electronic signal after the GBL drug adsorption, being a promising electronic sensor. The recovery time for GBL drug desorption from the Al-BC₃NT surface was predicted to be short (0.9 s). The interaction between the GBL and Al-BC₃NT was strengthened in the ethanol solvent, and the E_ad became more negative (-28.9 kcal/mol).