Facile and green synthesis of CuO nanoneedles with high photo catalytic activity

In this study, Cu(OH)(2) nanoneedles were synthesized by anodizing of copper foil in a 1 M aqueous solution of potassium hydroxide at a constant current density with a typical reaction time of 30 min at 5 A degrees C. Cu(OH)(2) nanoneedles were transformed into CuO nanoneedles by annealing at 200 A degrees C for 150 min. X-ray diffraction and field emission scanning electron microscopy (FESEM) were utilized to study crystalline phase and morphology of theses nanomaterials, respectively. FESEM analysis showed that Cu(OH)(2) nanostructures are uniformly grown on the surface of copper foil and are interlocked with each other and leads to a three-dimensional structure. These nanoneedles consists of a bundle of several irregular wires with an average diameter of about 70-90 nm. The photo catalytic activity of CuO nanoneedles was evaluated by monitoring the photo-degradation of methyl orange dye. Results demonstrated that these nanoneedles possess good photo catalytic activity. They were very stable and could be recycled without considerable loss of activity. Other dye and organic pollutants such as rhodamine B, methylene blue and p-Nitrophenol could also be photo-decomposed under identical conditions. These characteristics show the practical applications of these CuO nanostructures in environmental remediation.