C‐Doped g‐C3N4 for Enhanced Photocatalytic Degradation of Azo Dyes under Visible Light.

A type of photocatalytic agent graphitic carbon nitride (g‐C3N4) has been formed by the thermal polymerization of urea with citric acid, with various contents of C in its material (CN‐x). Through the characterization of its morphology, structure, chemical composition, and photoelectric properties, it is found that the introduction of C dopant enhances sunlight absorption and facilitates electron‐hole separation and charge transfer within the g‐C3N4 structure. By further optimizing the doping amount of C, the photocatalytic degradation rates of CN‐10 on Rh B, methylene blue and amaranth reached 97.2 %, 94.2 %, and 91.2 % within 40 min, which were 1.1 times, 1.3 times, and 2 times of the unmodified g‐C3N4, respectively. Sacrifice experiments showed that ⋅O2− and ⋅OH were the main active substances in the photocatalytic degradation of Rh B and amaranth. In the degradation of methylene blue, ⋅O2− and h+ were then the main active substances. [ABSTRACT FROM AUTHOR]