Comparison of photocatalytic activity of ZnO/activated carbon nanocomposites prepared by solid-state method and conventional precipitation method

Document Type : Research Paper


1 Chemical Engineering Department, University of Mohaghegh Ardabili, P.O. Box 56199-11367, Ardabil, Iran

2 Chemical Engineering Department, University of Mohaghegh Ardabili, Ardabil, Iran


ZnO/activated carbon nanocomposites (ZnO/ACns) were synthesized by applying two different solid-state and precipitation method. Precipitation method was run out with zinc chloride and sodium hydroxide as starting materials in the presence of activated carbon. The synthesized sample was calcined at 250 °C for 1 h. The preparation of nanocomposite by solid-state method was accomplished by heating a mixture of ZnCl2 and activated carbon at 250 °C for 1 h, leading to the formation of ZnO particles on the surface. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Photocatalytic activity of these ZnO/acnes was evaluated by the degradation of methyl orange under UV-light radiation. The SEM images of samples show that the agglomerations of particles are much less in solid-state method prepared samples. The results of EDS indicate that the ratio of Zn/C in the pure activated carbon and nanocomposites prepared by solid-state and precipitation methods were 0, 1.7 and 3.7 % (W/W), respectively. The XRD of the samples clearly shows that the sample prepared by the above routes has ZnO structures. Finally, ZnO/ACn prepared by the solid-state method showing better photocatalytic efficiency against methyl orange dye than composites made by precipitation method.