Theoretical evaluation of boron carbide nanotubes as non-enzymatic glucose sensors

Abstract Potential applicability of boron carbide nanotube (BCN) and its Al doped analogue (Al-BCN) as glucose (GLU) sensor is investigated using density functional theory (DFT) method. Adsorption of GLU on top of pristine BCN leads to an Eads, enthalpy and Gibbs free energy changes (ΔH and ΔG) of -14.10, -14.00, and − 0.72 kcal.mol− 1, respectively. Frontier molecular orbitals (FMO) analysis reveals that the electronic properties of pristine nanotube are not sensitive to the presence the GLU molecule. To measure the effect of doping method on the sensitivity of BCN toward GLU, two boron atoms are replaced by Al ones. The adsorption energy, in this case, is about − 24.10 kcal.mol− 1. The ΔH and ΔG resulted by the GLU adsorption on the Al-BCN surface are calculated to be -23.89 and − 10.85 kcal.mol− 1, respectively. The Eg of Al-BCN decreases by about 19.11% upon adsorption process and electronic properties of Al-BCN are more sensitive to the presence of GLU molecule. Detection power of Al-BCN is about 1.8 higher than that of pristine BCN. The required time for desorption of GLU from pristine and doped BCN is calculated to be 2.12 × 10− 6 and 4.60 × 10− 1 s, respectively.