Amine-functionalized Ti₃C₂T_x MXene-integrated Nanocomposite Membranes via Vapor-phase Interfacial Polymerization for...

Escalating anthropogenic CO₂ emissions and global decarbonization imperatives are catalyzing a paradigm shift toward membrane-based gas separation as a scalable and energy-efficient frontier for post-combustion CO₂ capture. This work reports a sustainable vapor-phase interfacial polymerization (VP-IP) method for fabricating polyamideselective layer in Ti₃C₂T_x-NH₂ MXene-incorporated thin-film nanocomposite (TFN) membranes for CO₂ separation. VP-IP eliminates hazardous volatile organic solvents and provides precise control over polymer chain growth, crosslinking density, and interfacial morphology. MXene serves as a CO_2-philic nanofiller, forming hierarchical nanoconfined transport channels that facilitate preferential CO₂ transport. The optimized TFN@0.5MX membrane with 0.5 wt.% Ti₃C₂T_x-NH₂ loading achieves CO₂ permeance of 389.28 GPU and CO₂/N₂ selectivity of 15.11 at 25 °C and 1 bar pressure. Temperature-dependent analysis reveals a notable increase in CO₂ permeance to 418.5 GPU with enhance CO₂/N₂ selectivity to 42.22 at 40 °C, surpassing both the 2019 and 2008 Robeson upper bounds. Systematic structure-performance correlations under varying thermodynamic conditions reveal a synergistic interplay between molecular sieving sorption selectivity and diffusion path tortuosity, wherein MXene acts as multifunctional sorption-selective nodes. This sustainable strategy offers a scalable and environmentally benign route for industrial CO₂ capture and circular carbon utilization, aligning with sustainability goals and advancing the transition toward low-carbon process intensification.