Supramolecular Synthesis of Multifunctional Holey Carbon Nitride Nanosheet with High‐Efficiency Photocatalytic Performance

Abstract Novel carbon nitride (CN) nanosheets are for the first time fabricated by facial supramolecular approach using cyanuric acid, melamine, and 2,4‐diamino‐6‐methyl‐1,3,5‐triazine as starting materials. This is also the first report where the third monomer is used in such synthetic route. With the unique structural advantages for efficient separation of photoinduced charge–hole pairs, light absorption, and the richly available restive sites, the as‐synthesized porous CN nanosheets exhibit a superior photocatalytic hydrogen evolution activity whether they are under simulated solar light or under visible light (λ > 420 nm) irradiation. The hydrogen evolution rate can reach 11 946.1 µmol h⁻¹ g⁻¹ under visible light irradiation, to the best of our knowledge, the highest of all the metal‐free CN semiconductor photocatalysts. Also, the synthetic holey CN nanosheets exhibit excellent photocatalytic oxidation performance of high concentration nitric oxide (NO, ≈400 ppm) and outstanding photocatalytic degradation of rhodamine B under visible light. The supramolecular synthesis of multifunctional CN nanosheets using suitable monomers as raw materials may provide a possible pathway for alleviating energy issues and environmental pollution problems.