Hydrothermal vs. electrodeposited CuxO for photocatalytic applications under simulated solar illumination

We have studied photocatalytic activity of CuxO coatings prepared by different methods. Electrodeposition resulted in compact CuxO coatings with small grain size, where x could be varied by changing the annealing temperature. Hydrothermal method resulted in thick, nanostructured black coatings which exhibited excellent photocatalytic activity. In addition, hydrothermal coating could be used repeatedly, and after repeated use initial performance could easily be recovered by briefly dipping the sample into a precursor solution for hydrothermal growth at room temperature. The properties of the coatings and their relationship to photocatalytic activity for degradation of organic dyes in presence of hydrogen peroxide is discussed in detail.