Adsorption behaviour of diatomic gases with defected hexagonal boron nitride nanosheet: a DFT study

It has been well reported that defects or dopants can significantly improve the sensitivity of gases adsorbing on the atomic thin layer materials. For instance, Fe, Co and Ni metal embedded in MoS₂ monolayer to increase the sensitivity for O₂ molecule, while non-metal or metal was doped in graphene to improve the sensitivity for gases. However, most of the works reported in references and literature are based upon the modification of defected region of BN sheet/nanotube with different doped metallic or non-metallic elements. These doped elements, as a consequence alter the local electron density which ultimately facilitates the interaction and thereupon adsorption of gaseous molecules onto the surfaces of BN. Although the activation of gas molecules through the transfer of electrons are already reported for many BN systems, but for the defected BN has not been intensively explored. Additionally, the defects in support matrix provide additional binding strength to enhance the stability for single atom catalyst. In the same line, we have tried to explore the stability and interaction behaviour of homo and hetero-atomic (CO, NO, Cl₂, H₂, N₂, O₂) gases with pristine, Bvacancy (BV) and N-vacancy (NV) defected hexagonal boron nitride nanosheet (h-BNNS). The general trend on the adsorption behaviour is that the NV system interacts strongly with the gas molecules than that of BV system