Efficient Sensing Properties of Aluminum Nitride Nanosheets toward Toxic Pollutants under Gated Electric Field

Based on density functional theory simulations, we explore the adsorption characteristics, charge transfer mechanism, and electronic properties of a range of selected toxic gases on aluminum nitride (AlN) sheets with and without the external electric field. Owing to the polarization of Al-N bond, the toxic gases can be directly adsorbed by AlN in its pristine form, which avoids the problem of creating systematic defects and metal doping on AlN. Among the studied gases, the AlN sheet adsorbs SO2, NO2, NH3, and CO2 more efficiently. We find that the presence of the toxic gases under the application of electric field not only improves the binding mechanism but also results into significant changes in the electronic characteristics of the AlN sheet. Our findings provide an insight into regulating the sensing properties of AlN in the presence of an applied electric field. Based on these results, we firmly believe that AlN has a great potential to be used as an efficient nanosensor for SO2, NO2, NH3, and CO2 gases.