Asymmetric Graphene Oxide Membrane for Selective Hydrogen Separation at Room Temperature

Abstract Hydrogen purification membranes are crucial for fuel cell technologies and low-carbon energy applications. However, conventional membrane systems suffer from a permeability-selectivity trade-off and often require high operating temperatures. Here, we report a room-temperature hydrogen separation membrane with an asymmetric architecture, consisting of a thin, partially reduced sulfonated graphene oxide (As-PrSGO) intercalated with cerium (As-PrSGOCe) on a porous carbon paper support. The tailored interlayer chemistry and controlled partial reduction yield mixed proton and electron conductivities of 1.13 and 1.19 mS cm−1, respectively, achieving hydrogen fluxes up to 0.15 mL min−1 cm−2 at 25 °C with undetectable He permeation. This flux is comparable to values reported for mixed-conducting ceramic membranes operated at 600−950 °C, while the asymmetric structure ensures mechanical robustness and stable operation over 70 h. By resolving GO’s intrinsic trade-off between ionic and electronic transport under mild conditions, this work establishes a scalable, energy-efficient alternative to palladium based and high-temperature ceramic ceramic membranes. These findings advances carbon-based mixed-conducting membranes as practical platforms for hydrogen purification under ambient-conditions