Investigation of Sarin Nerve Agent Adsorption Behavior on BN Nanostructures: DFT Study

The adsorption behavior and electronic response of BN nanosheet, nanotube, and nanocage to sarin gas, a nerve agent, were studied using density functional theory calculations. The adsorption energy is increased by increasing the BN nanostructure curvature, and it is about - 0.5, - 1.6, and - 3.4 kcal/mol for BN sheet, tube, and cage, respectively. The BN sheet and tube are insensitive to sarin gas. Although the BN cage is sensitive, it suffers from a weak interaction, and low adsorption capacity. To overcome this problem the BN cage is doped with different impurity atoms including, Sc, Al, Si, and C. The Sc and Al dopings significantly increase the reactivity of BN cage to sarin but the sensitivity is not increased sensibly. The Si and C dopings make the BN cage more reactive and sensitive to sarin gas. The C-doped BN nanocage may be a promising sensor because of its higher sensitivity, compared to the Si-doped one. After the sarin adsorption on the C-doped BN cage, its gap decreases by about 64.0% which exponentially increases the electrical conductivity, creating an electrical signal. Also, the recovery time is about 7.9 x 10(15), 1.4 x 10(23), 0.004, and 0.013 s for Sc, Al, Si, and C-doped BN cages, respectively.