Fabrication of Ag-doped ZnO by mechanochemical combustion method and their application into photocatalytic Famotidine degradation.

Ag/ZnO nanocomposites are successfully synthesized at different Ag contents through simple, effective, high yield and low-cost mechanochemical combustion technique, with the addition of silver acetate to zinc acetate and oxalic acid mixture. The synthesized materials are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron spectroscopy (SEM), BET surface area analysis, UV - visible diffuse reflectance spectroscopy (UV - DRS) and photoluminescence spectroscopy (PL). It is shown that the prepared nanocomposites are composed of metallic Ag0 and wurtzite ZnO. The photocatalytic performance of different composites is evaluated by the degradation of Famotidine (FMT) under UV irradiation. The results indicate it that the maximum photodegradation rate is obtained with 6 wt% metallic Ag-decorated ZnO, and it is 2.1 times better than that obtained with pure ZnO. The photocatalytic degradation of FMT with Ag/ZnO is affected by various parameters such as calcination temperature and time, doping concentrations and reusability. The Ag/ZnO demonstrates higher activity due to the reduction of electron - hole recombination and Ag0 metal catalyst. The possible photocatalytic degradation mechanism of FMT with Ag/ZnO is estimated from the scavenger test.