Achieving Efficient Incorporation of π‐Electrons into Graphitic Carbon Nitride for Markedly Improved Hydrogen Generation

• Published in: Angewandte Chemie International Edition 2019-02, Vol.58 (7), p.1985-1989
• Main Authors: Li, Jing, Wu, Dandan, Iocozzia, James, Du, Haiwei, Liu, Xueqin, Yuan, Yupeng, Zhou, Wei, Li, Zhen, Xue, Zhaoming, Lin, Zhiqun
• Format: Article
• Language: English
• Subjects: Acids; Carbon nitride; Copolymerization; Electric furnaces; Electrons; Heating; Hydrogen production; Melamine; microwaves; Monomers; photocatalysis; Sublimation; Volatilization; π-electrons
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201813117

A rapid and highly efficient strategy for introducing C into g‐C3N4 involves copolymerizing π‐electron‐rich barbituric acid with melamine via a facile microwave‐assisted heating, thereby eliminating the issues in conventional electric furnace heating, such as the severe volatilization, owing to the mismatch of the sublimation temperatures of barbituric acid and melamine. The g‐C3N4 catalyst after optimizing the C‐doping content actively generates increased amounts of H2 under visible light exposure with the highest H2 generation rate of 25.0 μmol h−1, which is nearly 20 times above that using g‐C3N4 produced by conventional electric furnace heating of two identical monomers (1.3 μmol h−1). As such, the microwave‐assisted heating strategy may stand out as an extremely simple route to incorporating π‐electrons into g‐C3N4 with markedly improved photocatalytic performance. π‐Electrons were rapidly and efficiently incorporated into the g‐C3N4 by copolymerizing π‐electron‐rich barbituric acid with melamine via a microwave‐assisted heating process. The as‐produced g‐C3N4 shows a near 20‐fold enhancement in H2 generation upon exposure to visible light, representing a rate of 25.0 μmol h−1 over 1.3 μmol h−1 from g‐C3N4 produced by conventional heating in an electric furnace.