Molecular dynamics simulation of CO₂/CH₄ separation performance in graphene/g-C₃N₄ hybrid lamellar membrane

With the accelerating climate change driven by CO 2 emissions, the development of CO 2 separation technologies has become essential for achieving global carbon neutrality targets. This work investigates the CO 2 /CH 4 separation performance of graphene/g-C 3 N 4 hybrid lamellar membrane using molecular dynamics (MD) simulations. The simulation results reveal that the CO 2 permeance increases with larger interlayer spacings in the nanochannel. Specifically, the CO 2 permeances at interlayer spacings of 6.0, 6.5, and 7.0 Å are 9.65 × 10 – 4, 1.61 × 10 – 3, and 2.29 × 10 – 3 mol·s – 1·m – 2·Pa – 1, respectively. The CO 2 /CH 4 selectivity reaches 100% at interlayer spacings of 6.0 and 6.5 Å but decreases to 30.77 at 7.0 Å due to CH 4 permeation. These findings highlight the potential of graphene/g-C 3 N 4 hybrid lamellar membrane for CO 2 /CH 4 separation, with the interlayer spacing serving as a critical factor in optimizing both CO 2 permeance and selectivity.