Fast Exfoliation and Functionalisation of Two‐Dimensional Crystalline Carbon Nitride by Framework Charging

Two‐dimensional (2D) layered graphitic carbon nitride (gCN) nanosheets offer intriguing electronic and chemical properties. However, the exfoliation and functionalisation of gCN for specific applications remain challenging. We report a scalable one‐pot reductive method to produce solutions of single‐ and few‐layer 2D gCN nanosheets with excellent stability in a high mass yield (35 %) from polytriazine imide. High‐resolution imaging confirmed the intact crystalline structure and identified an AB stacking for gCN layers. The charge allows deliberate organic functionalisation of dissolved gCN, providing a general route to adjust their properties. A scalable one‐pot reductive method produces stable solutions of single‐ and few‐layer two‐dimensional graphitic carbon nitride (gCN) nanosheets in high yield (35 %). Atomic‐resolution imaging confirms an undamaged crystalline structure with AB stacking. The anionic charge provides a versatile route for functionalisation, as illustrated by alkylation.