  The adsorption and desorption of carbon dioxide (CO2) molecule by alkaline
earth metal (AEM) (Mg+2, Ca+2, Sr+2 and Ba+2) functionalized on graphitic boron
nitride (g-B4N3) nanosheet have been analyzed by using density functional
theory (DFT) approach includes long-range correlation (DFT+D). This method has
been implemented in such a way to understand the switchable or capture/release
mechanism of CO2 molecule by computing the electron mobility, electronic
properties, charge accumulation, charge transfer (e-) and adsorption energy
(Kcal/mol). The g-B4N3 nanosheet yields high carrier mobility (8020 cm2 V-1s-1)
at 300 K. The positive alkaline earth adatoms on the nanosheet of g-B4N3 has
been provided external energy to do the capture/release process of greenhouse
gas CO2. Here, Mg positive ion work as adatom which confirms physisorption
while others show chemisorption behaviors. Therefore, due to the weak
absorption of CO2, it makes possible to discharge from the g-B4N3 nanosheet and
shows instantaneous switching mechanism. Briefly, the negatively charged g-B4N3
nanosheets are highly sensitive for CO2.
