Photocatalytic and Fenton-like Photocatalytic Activity of C-doped ZnO Nanoparticles in the Degradation of Malachite Green in a Water

The C-doped ZnO nanoparticles were synthesized by sol-gel method using different amount of propylene glycol as a complexing agent. The propylene glycol led to the doping of C into the nanoparticles, and the C content in the nanoparticles increased as increasing the amount of propylene glycol. The nanoparticles showed excellent photocatalytic activity in photodegradation of malachite green dye in water. The C-doping expanded the light absorption of the nanoparticles to long wavelength and so speeded up the photodegradation of thye dye. Significantly, the nanoparticles also can completely decolorize the malachite green within a short period in the present of hydrogen peroxide, showing remarkable Fenton-like photocatalytic activity. An optimal H2O2 dosage was observed. The Fenton-like reaction was more faster as increasing the C content and decreasing the average particle size of the ZnO nanoparticles. The quasi-kinetic rate constants of the photocatalysis systems are in the range of ~0.0462–0.0700 min-1 and increase to ~0.112–1.498 min-1 by synthetically using H2O2.