Self‐Assembly of Hollow, Pompon‐Like and Nanosheet‐Structured Carbon Nitride for Photodegradation of Tetracycline Hydrochloride

Abstract A hollow pompon‐like carbon nitride (hp‐CN), composed of nanosheets, is prepared and used for photocatalytic degradation of tetracycline hydrochloride (TC). The synthesis is done by a supramolecular self‐assembly method, using melamine and cyanuric acid as precursors. The hollow pompon‐like morphology and nanosheet structure promote both the textural (e.g., crystallinity, surface area) and electronic properties (e.g., electron–hole separation efficiency, number of excited electrons, and impedance) of hp‐CN, compared to these of graphitic carbon nitride (g‐CN) synthesized by direct polycondensation of melamine. The hp‐CN‐6 (heating for 6 h) is highly active for photodegradation of TC, with 96.3% conversion obtained within 15 min when conducted at pH 1.86, and no appreciable activity loss is detected within 4 cycles. Quenching experiments suggest that superoxide radicals (•O 2 − ) are the primary active reaction species. A comparison in the activity of hp‐CN‐6 and g‐CN for photocatalytic TC degradation is made, and a possible mechanism is proposed.