Structural Analysis and Growth Mechanism of Zn/ZnO Nanowires in AAO Template by Electrodeposition

To fully understand the mechanism of forming Zn and ZnO nanowires in electrodeposition, Anodic Alumina Oxide (AAO) membrane was used to electrodeposit Zn/ZnO nanowires by varying the potential. The structure of electrodeposited Zn/ZnO nanowires is studied by means of X-ray diffraction and scanning electron microscopy. Different deposition parameters were used to obtain different structure of electrodeposited nanowires. At -1.4 V with pH2.5, the pure Zn nanowires are electrodeposited. By lowering the potential to -1.0 V with same electrolytic concentration and pH, the formed nanowires are mixture of Zn and ZnO. Further decrease in potential to -0.6V, electrodeposited nanowires are of pure ZnO. The size of the critical cluster decreases with increasing the over potential. The formation of pure ZnO nanowires can be attributed to the formation of large size critical Zn nuclei, the larger size of nuclei favors the formation of pure zinc oxides nanowires