Electrochemical synthesis of nanostructured ZnO films, Mn and Al doped and photocatalytic activities

In this study, uniformity and reproducibility of well-defined nanostructured ZnO films were studied in different morphologies (rod, plate, flowers), by changing the critical parameters of electrochemical deposition method. For this purpose, the effect of various supporting electrolytes (KCl, CH3COONH4 ve CH3COONa) has been investigated. It was also studied and explained in detail, the mechanism of shifting the morphology from rod to plate to flower like structure of ZnO with the help of FE-SEM and XRD analyzes. The energy band gap (Eg) values, electronic and surface properties were determined by UV-Vis analysis, Mott-Schottky and contact angle measurements, respectively. It was found that the ZnO nanoplate morphology exhibiting high catalytic activity which can offer the advantage of effectively collecting and distributing sunlight (Light Harvesting Assembly). Also, in order to increase the catalytic properties of nanoplate structured ZnO films, Mn and Al were added in the synthesis solution, at different concentrations during the electrodeposition. The effects of dopants on the morphological, crystallographic, optical, electronic properties and band structure of ZnO nanostructures were investigated in detail. It has been determined that the band gap (Eg) of ZnO nanostructures are decreased to 2.60 eV and their electronic and crystallographic properties are improved by doping Mn and Al. These properties have been tried to be elucidated by associating with the activity of the electrodes during the photocatalytic degradation of ethanol. The Al and Mn-doped ZnO nanostructures exhibit much higher catalytic activity than the pure ZnO nanostructures, respectively.