Random Oriented ZnO Nanorods Fabricated through Anodization of Zinc in KHCO₃ Electrolyte

Abstract

Randomly oriented zinc oxide (ZnO) nanorods with an average width of 150 nm were fabricated through anodic oxidation of zinc foil in aqueous KHCO 3 electrolyte. Under the optimization of anodic parameters randomly and well oriented nanorods were obtained with randomly oriented nanowires beneath the structures. The growth mechanism of nanorods by optimization of anodization parameters and optical properties were studied in detail through scanning electron microscopy, X-ray powder diffraction, and UV-visible spectrometry The results obtained show that the prime factor affecting the morphology of nanorods is the applied voltage during anodization, while other anodic factors such as anodization time and concentration of electrolyte play a minor part in tuning the morphology. The optical spectrum shows the blue shift in the bandgap indicating applications in UVvisible sunlight electrode materials and photoanodes for water splitting purposes and electrodes in supercapacitors. The specific capacitance of 93.75 F g −1 at a scan rate of 100 mVs obtained using a three electrochemical cell display better performance in charge storing devices and will act as a potential candidate for electrodes used in supercapacitors.

Anodization fabrication techniques and energy-related applications for nanostructured anodic films on transition metals

“…As the anodization time increased, the morphology of the anodic films was transformed gradually from discrete nanoflower-like structures to a uniform film of aligned nanowires [Figure 7]. Numerous follow-up studies further revealed that the nanowire length and diameter and density of the nanoflower-like structures were directly proportional to the anodization time [149][150][151][152][153][154] . In addition, nanowires can be grown at a rather high rate (~1.3 μm min -1 ) [149][150][151][152][153][154] in an aqueous KHCO 3 solution.…”

“…Numerous follow-up studies further revealed that the nanowire length and diameter and density of the nanoflower-like structures were directly proportional to the anodization time [149][150][151][152][153][154] . In addition, nanowires can be grown at a rather high rate (~1.3 μm min -1 ) [149][150][151][152][153][154] in an aqueous KHCO 3 solution.…”