(202f) Kinetic Control of Intrinsic Pores in Monolayer Graphene for Large-Area Proton Selective Membranes

Angstrom scale proton selective defects introduced into the lattice of atomically thin 2D materials such as graphene viascalable processes present potential for transformative advances as membranes for energy conversion/storageapplications. Here, we show for the first time that kinetic control of graphene synthesis during chemical vapordeposition (CVD) can allow for tunable Angstrom scale proton selective pores for facile fabrication of large-areaatomically thin proton exchange membranes. Using a resistance-based transport model in conjunction with systematicliquid and gas phase transport measurements on the same membrane, we study the influence of such Angstrom scaleintrinsic defects on selective proton transport through centimeter-scale Nafion|Graphene|Nafion sandwich membranes.Additionally, we report on a novel graphene stacking approach that effectively mitigates transport of un-desiredspecies(small ions and gas crossover)without adversely affecting proton transport. Our insights on kinetic control ofgraphene synthesis for Angstrom scale pore formation over large areas as well as facile stacking approach formembrane fabrication offer new avenues to enable functional large-area atomically thin proton exchange membranes.