Adsorption and photocatalytic degradation of Carbendazim by ZnO nanoparticles: A joint theoretical and experimental study

The present work is focused on the adsorption and photodegradation of carbendazim on the surface of ZnOnano-particles. The reaction carried out in a Pyrex photoreactor equipped with a Krypton lamp. The effect of initialconcentration under UV light irradiation is examined. The kinetic of the removal is explained in terms of the Langmuir–Hinshelwood model. The values of the adsorption equilibrium constant, K, and the kinetic rate constant of surfacereaction, kc, are calculated. the results show that more than 90 percent of the substrate is removed after 90 minutes. Toobtain the adsorption properties, the ZnO surface is modeled as two clusters, Zn21O36H30 and Zn12O18H12. In the theoreticalstudy, geometry optimization and vibrational analysis for adsorption on cluster is calculated by density functional theorymethod at B3LYP/lanl2DZ level. The results show that the adsorption energies depend on the surface model and organiccompound prefers to be adsorbed molecularly on the ZnO (0001) surface.

Keywords:

Adsorption , ZnO , Photodegradation , DFT , Nanoparticle