Seconds-scale exfoliation of high-quality 2D crystals enabled by polycyclic aromatic hydrocarbon radical anion-mediated organoalkali intercalation

Scalable production of high-quality 2D nanosheets remains challenging because existing top-down and bottom-up methods typically face a trade-off between material quality, yield, and cost. Here, we report the seconds-scale (~12 s) production of high-quality 2D crystals via polycyclic aromatic hydrocarbon radical anion (PAH•-)-mediated organoalkali intercalation. The tunable reduction potential and electron-transfer capability of PAH•- enable ultrafast alkali-ion intercalation within seconds in the stable potential of layered hosts. For graphite, sodium naphthalenide (Na-Naph) forms a stage-1 graphite intercalation compound in only 1 s, and subsequent hydrolysis-driven exfoliation in 11 s yields graphene with >88% yield and >50% single-layer ratio, with a negligible increase in defect density (ID/IG ratio from ~0.10 to ~0.11). This strategy is further extended to the exfoliation of few-layer (3-5 layers) transition-metal sulfides, selenides, and tellurides while preserving their intrinsic crystal phases. This work establishes a practical, high-yield route for rapid intercalation-driven exfoliation, offering a scalable platform for manufacturing high-quality 2D crystals. The scalable and cost-effective production of high-quality 2D nanosheets remains challenging. Here the authors report the seconds-scale production of high-quality 2D crystals (graphene and transition metal dichalcogenides) via polycyclic aromatic hydrocarbon radical anion (PAH•-)-mediated organoalkali intercalation and subsequent hydrolysis-driven exfoliation.