Thiourea adsorption effect on electrical properties of boron nitride nanotubes

Boron nitride nanotubes due to their great features have attracted more attention to use in different fields. Great adsorption capacity gives this opportunity to those to be used as an adsorbent for various molecules. In this work, we tried to theoretically study the adsorption of thiourea on the three armchairs (n,n) of boron nitride nanotube, where n = 5, 6, and 7. In this attempt, density functional theory is applied to study the behavior of electronic properties of BNNTs after reacting to a single thiourea molecule. The results of HOMO and LUMO energies of complexes confirm that this adsorption leads to reducing the bandgap energies, and therefore, increasing the conductivity of the BNNTs. The negative values of binding energies show the thermodynamical tendency of nanotubes toward this reaction. In addition, the changes around the Fermi level of the complexes calculated by the total and partial density of states analyses confirm the change of electronic properties of BNNTs due to thiourea adsorption.