Lewis Acid-Base Adducts for Improving the Selectivity and Sensitivity of Graphene Based Gas Sensors

The first-principles calculations are performed to study the gas (NH₃, NO₂, NO, and N₂O) sensing properties of pure and doped (B@, Al@, and Ga@) graphene surfaces. Interactions between the gas (NH₃, NO₂, NO, and N₂O) and the graphene surfaces are improved due to the doping on graphene. So, the dopants are carefully chosen to form the Lewis acid-base pairs between the dopants and gas molecules. Formation energy calculations and ab initio molecular dynamics simulations (AIMD) are carried out to evaluate their thermodynamic and thermal stabilities, respectively. The electronic properties of the Al@graphene change significantly when a selective gas molecule (NO₂) is adsorbed. Thus, we report that Al@graphene can be a promising material for the highly selective and sensitive semiconductor based gas sensor.