The dynamic motion makes small pores CO2 permeable, which would otherwise be impermeable with rigid PLD. The strong interaction of CO2 with C=O ensures adsorbed-phase transport even at elevated temperatures, resulting in a selective gating of CO2 over O2 and N2 even from large pores, which would otherwise be nonselective. Finally, a quantitative agreement is achieved between the flux predicted by the transition-state-theory (TST) calculations and the translocation rates from the MD simulations. This will allow one to avoid time-consuming and expensive simulations. These insights highlight the unprecedented high potential of porous graphene membranes for carbon capture and will inspire improved membrane design.