Photocatalytic oxidation for efficient 4-chloro-guaiacol degradation over Co-doped graphitic carbon nitride and the effect of Co-doping concentration on optical properties of carbon nitride

This paper investigates the fabrication of Co-doped carbon nitride (C 3 N 4 -Co) and its application in degrade 4-chloro-guaiacol. Co-doped carbon nitride significantly enhanced the photocatalytic activity for 4-chloro-guaiacol degradation compared to unmodified carbon nitride. Under the same conditions, the degradation rate of 4-chloro-guaiacol by unmodified C 3 N 4 was only 30.7 %, however it increased to 73.7 % by Co-doped carbon nitride (0.25 wt%). Co-doping can extend the wavelength range, improve oxygen adsorption, and reduce electron-hole recombination. However, the greater the amount of Co-doping. But, when the doping level is too high, excessive oxygen adsorption may occur on the surface of the active site, obstructing 4-chloro-guaiacol adsorption and reducing the catalytic efficiency. This work could provide useful information regarding AOX degradation for future research.