Nanosize pore arrays, which have been prepared by the self-organization process of aluminium anodic oxidation, were investigated quantitatively using fast Fourier transformation analysis of scanning electron microscopy micrographs. The results show that the temperature influences the pore domain size and the best self-ordering configuration is obtained at an optimum condition of temperature. The largest domain size was observed for samples anodized around 15°C to 17°C, using 0.3 M oxalic acid. It is also found that the optimum temperature for self-organization of pore oxidation changes in accordance with the concentration of electrolyte.

ZnO nanorod (NR) arrays were grown by a simple two-step chemical bath deposition method. The as-deposited NRs were then annealed at different temperatures (300, 400 and 500°C) for two time durations (1 and 5 h). The NRs were studied by scanning electron microscopy, photoluminescence spectroscopy, X-ray diffraction and two-point electrical test. Finally, ultraviolet (UV) detection properties of samples as an active layer in UV photodetector devices were evaluated. The structural results showed that the sample annealed at 400°C had the best crystallinity. Furthermore, it was seen that the optical transparency and band gap of NRs increased with increase of the annealing temperature up to 400°C and then decreased at 500°C. The electrical resistance decreases with increment of the annealing temperature due to intensive desorption of oxygen molecules from the surface of ZnO NRs. The UV detection results proved a meaningful relevance of UV detection properties with the density of defects and quantity of oxygen molecules absorbed on the surface. ZnO NRs annealed at 300°C for 1 h had the highest photosensitivity of 300 and photoresponsivity of 2.067 A/W which make it suitable for the practical applications.

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High-density structures with well-ordered nanohole arrays have been obtained by the self-ordering growth of nanopores using 25–40 V anodization voltages in a sulfuric–oxalic acid mixture. In each anodization voltage, two types of electrolyte mixture were used with low and high sulfuric concentrations at a constant pH value. The ordering and regularity of a nanohole array was quantified by analysis of fast Fourier transformations of scanning electron and atomic force microscope images. The results show that the long range ordering of nanohole array is superior for high sulfuric concentration, while regularity is more pronounced for low sulfuric concentration. The interpore distance in the oxalic–sulfuric mixture is higher in the case of low sulfuric concentration. It is almost proportional to 2.6 nm V−1 and 2.5 nm V−1 for the electrolyte mixture with low and high sulfuric concentrations, respectively. While the porosity is nearly 10% for samples made in standard sulfuric and oxalic acid using 25 V and 40 V anodization voltage, respectively, it increases up to 50% for the sample made with 37.5 V in an oxalic–sulfuric mixture.

Whilst Co nanorods with high coercivity were synthesized during recent years, they did not achieve the same results as for Co nanowires embedded in solid templates. In the present work, Co nanowire arrays (NWAs) with high coercivity were successfully fabricated in porous aluminum oxide template under optimum conditions by using pulsed ac electrodeposition technique. Magnetic properties and crystalline characteristics of the nanowires were investigated by hysteresis loop measurements, first-order reversal curve (FORC) analysis, X-ray diffraction (XRD), and selected area electron diffraction (SAED) patterns. Hysteresis loop measurements showed high coercivity of about 4.8 kOe at room temperature together with optimum squareness of 1, resulting in an increase of the previous maximum coercivity for Co NWAs up to 45%. XRD and SAED patterns revealed a single crystalline texture along the [0002] direction, indicating the large magnetocrystalline anisotropy. On the other hand, FORC analysis confirmed a single domain structure for the Co NWAs. In addition, the reversal mechanism of the single crystalline, single domain Co NWAs was studied which resulted in the fixed easy axis with a coherent rotation. Accordingly, these nanowires might offer promising applications in high density bit patterned media and low power logic devices.