Enhanced adsorption of Cu2+ from aqueous solution by Ag doped nano-structured ZnO

Ag doped nano-structured ZnO film on glass slide was prepared by the microwave force hydrolysis method. The prepared film was characterized using X-ray diffraction, energy-dispersive X-ray spectroscopy and scanning electron microscopy methods. The structure of deposited ZnO is flower-like with a particle size of <3 mu m and a crystalline size of 22.7 nm. The equilibrium and kinetics of adsorption of copper ion from an aqueous solution by the Ag doped ZnO were studied. Addition of small amounts of Ag to the nano-structured ZnO improves both the rate of adsorption and maximum adsorption capacity. The effect of Ag on the improved adsorption behavior of ZnO was discussed based on the presence of Ag in the substitutional Zn sites of ZnO. And finally a mechanism for the adsorption of copper ion on Ag/ZnO was proposed. (c) 2014 Elsevier B.V. All rights reserved.