Acid-Free Synthesis of MIL-101/GO Composites with Ultrahigh Selectivity for Adsorptive Separation of C3F8 from N2

Highlights What are the main findings? A green acid-free route produces MIL-101/GO-0.1, enabling superior C 3 F 8 capture. The content of graphene oxide affects the adsorption properties of the composite material. MIL-101/GO-0.1 achieved a record-breaking IAST separation selectivity of 17,069 for C 3 F 8 /N 2 . What are the implications of the main findings? Overcome the current technical bottleneck of low C 3 F 8 adsorption capacity. Green synthesis coupled with high adsorption capacity opens up possibilities for industrial applications. This provides insights for future research into the adsorption and separation of C 3 F 8 . As a perfluorinated compound with a high global warming potential, octafluoropropane (C 3 F 8 ) needs to be efficiently separated from industrial waste gas, but separating it from nitrogen at low concentrations is highly challenging. To address the common drawback of using corrosive acids in conventional MIL-101(Cr) synthesis, this study developed a green, acid-free solvothermal method for preparing graphene oxide (GO)-modified MIL-101(Cr) composites (MIL-101/GO). By systematically varying the GO doping, the optimal composite (MIL-101/GO-0.1) exhibited breakthrough adsorption performance: its equilibrium adsorption capacity for C 3 F 8 reached 210 mg/g in fixed-bed breakthrough experiments. The predicted C 3 F 8 adsorption selectivity relative to N 2 reached 17,069, ranking among the highest values reported for adsorbents, indicating a significant performance enhancement over the pristine MIL-101(Cr). Mechanistic analysis reveals that graphene oxide not only increases specific surface area and micropore volume but also enhances dispersion forces, substantially boosting affinity for C 3 F 8 . Additionally, the composite exhibits outstanding cycling stability and thermal stability. This study provides a novel eco-friendly synthetic strategy for high-performance metal–organic frameworks and offers a highly promising candidate material for industrial-scale fluorocarbon recovery.