A Rapid Microwave‐Assisted Thermolysis Route to Highly Crystalline Carbon Nitrides for Efficient Hydrogen Generation

Highly crystalline graphitic carbon nitride (g‐C 3 N 4 ) with decreased structural imperfections benefits from the suppression of electron–hole recombination, which enhances its hydrogen generation activity. However, producing such g‐C 3 N 4 materials by conventional heating in an electric furnace has proven challenging. Herein, we report on the synthesis of high‐quality g‐C 3 N 4 with reduced structural defects by judiciously combining the implementation of melamine–cyanuric acid (MCA) supramolecular aggregates and microwave‐assisted thermolysis. The g‐C 3 N 4 material produced after optimizing the microwave reaction time can effectively generate H 2 under visible‐light irradiation. The highest H 2 evolution rate achieved was 40.5 μmol h −1 , which is two times higher than that of a g‐C 3 N 4 sample prepared by thermal polycondensation of the same supramolecular aggregates in an electric furnace. The microwave‐assisted thermolysis strategy is simple, rapid, and robust, thereby providing a promising route for the synthesis of high‐efficiency g‐C 3 N 4 photocatalysts.