Carbon dioxide is a well-known greenhouse gas that cause global warming. CO2 capture and sequestration strategy is known promising strategy to reduce the level of CO2 in the atmosphere. Thus, the usage of Amino Acid Ionic Liquids have gained attention for reversible CO2 capture. Herein, we use DFT to report the effect of CO2 chemisorption on tetramethylphosphonium glycinate and tetrabutylphosphonium glycinate ILs. Finally, Molecular Dynamics (MD) simulations were carried out to study the physicochemical properties of ILs in pure form and in the presence of explicit water. Overall, our study confirms the usage of studied ILs to efficiently capture CO2.