Boosting Decarbonization Efficiency of Anisotropic Dual‐Layer Composite Membranes Containing MOF ‐5 and Graphene Nanoplates

Decarbonization is essential to address climatic variations caused by greenhouse effects. Membrane‐based separation processes present an energy‐efficient and scalable pathway for flue gas purification. Permeability‐selectivity trade‐off of polymeric membranes can be mitigated through combined impregnation of bi‐fillers within polymer matrix coupled with applying ultrathin secondary polymer coating to fabricate efficacious dual‐layer composite membrane. Microporous activated MOF‐5 nanocrystals with high surface area and CO 2 affinity, combined with graphene nanoplatelets possessing exceptional CO 2 uptake, were synergistically embedded into flexible polysulfone matrix. Biodegradable poly(vinyl alcohol) coating layer was uniformly deposited onto doped polysulfone substrate, yielding novel class of anisotropic dual‐layer mixed matrix composite membranes, rendering drastically improved CO 2 /N 2 selectivity of 70 and upgraded CO 2 permeability of 92 Barrer as compared to bare polysulfone membrane. Advanced characterizations verified uniform nanofiller dispersion, strong interfacial bonding, and enhanced thermal stability. Five percent PVA coating boosted thermal stability and improved mechanical robustness by 84%, markedly strengthening membrane structural and thermal resilience. An effective strategy is introduced to produce dual‐layer membranes with remarkable CO 2 capture performance via optimized bi‐filler loading and PVA based surface modification.