Regulating interlayer spacing of aminated graphene oxide membranes for efficient flow reactions

Nanoconfinement effect can significantly impact chemical reactivity. Chemists design various porous nanoconfined systems to catalyze reactions. However, using these artificial systems for effective flow reactions under mild conditions remains a challenge. Here, we prepare multilayer aminated graphene oxide (GO-NH2) membranes to realize rapid and efficient Knoevenagel condensation with directional flow. Reducing the interlayer spacing (20.5–14.7 Å) of GO-NH2 membranes leads to an increase in reaction conversion. When the interlayer spacing is 14.7 Å, the conversion reaches ∼100% at 22°C with a short reaction time. Compared with the bulk reaction, the mechanistic study shows that interlayer confinement enhances the matching of the frontier orbital symmetry of reactants. The characterization of catalysts and density functional theory calculation prove that the delocalized π electrons of graphitic domains on GO-NH2 can reduce the overall confined reaction energy level. This work provides ideas for constructing artificial catalytic systems with high conversion under mild conditions.