Fig. 6: Transition state theory for predicting CO₂ translocation across 2D graphene pores.

a Schematic of the transition state theory of a gas translocating across graphene pores. \(\triangle {A}^{{\ddagger} }\) is the free energy of pore translocation. b Comparison of energy barrier \((\Delta {{\rm{E}}})\) estimated using MD and TST for CO₂ translocation through different pores (c) Comparison of translocation prefactor (A_trans) estimated using MD, TST (323 K) and corrected TST predictions (323 K) for CO₂ translocation through different pores. (d) Comparison of the translocation rates obtained from MD simulations and TST calculations for CO₂ translocating through different pores. (e) Comparison of the translocation rates obtained from MD simulations and corrected TST calculations for CO₂ translocating through different pores. (f) Comparison of CO₂/O₂ mixture selectivity obtained from MD simulation and corrected TST calculations for pore-16. (g) CO₂/O₂ mixture selectivity and CO₂ permeance for state-of-art polymeric membranes and graphene pores as a function pore density. (h) CO₂/N₂ mixture selectivity and CO₂ permeance for state-of-art polymeric membranes and graphene pore-16 as a function pore density. Robeson upper bond is represented for a selective layer of 1 micrometer in panels g and h (dashed line)⁸².