Solar‐Active Carbon Nitride Film Integrated by Free Radical Copolymerization for Photocatalytic Indoor Air Purification

Abstract The current lack of stable, scalable, and efficient coating technology dramatically limits the exploitation of solar‐driven graphitic carbon nitride (CN) photocatalysts. Herein, a unique, efficient, and scalable method is reported to immobilize CN powder on various substrates ranging from Fluorine tin oxide (FTO), glass, Plexiglas, Al foil, Ti foil, and Granite stone, to even wood. The film shows an outstanding thickness of 212 µm, which is the highest value ever reported. The formation process is ascribed to free radical copolymerization between the tri‐s‐triazine backbone and polyacrylamide, followed by cross‐linking. The smooth, non‐oxidizable, and well‐defined continuous coating exhibits excellent adherence and durability. The distinctive sequence segments preserve the light transition within the film while enhancing the optical absorption in the solar spectrum. Under visible light illumination, the film shows outstanding photodegradation performance toward air pollutants, whether for gaseous acetaldehyde (Act) or toluene (Tol). This method is a great step forward that can open new opportunities for the commercial applications of CN powder.