Two-step Anodization Research Articles

Fabrication of nanoporous alumina in 0.3 M oxalic acid and study on mechanical properties using micro indentation test

Anodic nanoporous alumina is becoming increasingly used as a material for the fabrication of nano and micro devices in a biomedical equipment, drug delivery system, corrosion resistive coatings, and range of industries. Because of its ease of production and low manufacturing cost, nanoporous alumina is becoming a more essential nanomaterial templet for a variety of applications such as micro filtration, sensors, optical device development, and tissue engineering. In this research, the fabrication of nanoporous alumina was fabricated using 0.3 M oxalic acid (C2H2O4) at constant voltage DC 60 V using a two-step electro chemical anodization process. Scanning electron microscopic (SEM) images revealed the regular honeycomb structure was formed, having an average pore diameter (Dp) of 48 nm, an interpore distance (Dc) of 125 nm, and a thickness of 98.5 µm with 26.7%. Energy dispersive x-ray spectroscopy (EDS) analysis was performed right after fabrication for chemical component analysis, and it confirms that the fabricated nanoporous membrane has a dominance of aluminum oxide (Al2O3). Finally, the mechanical properties (hardness and elastic modulus) of alumina were analyzed using micro indentation using the Micro Combi Tester (CMS 300) using the Oliver and Pharr method for two loading conditions: 0.05 N and 0.5 N.

Fabrication and thermal transient analysis of Ni-P sealed anodic aluminium oxide for electronic packaging

In recent years, suitable coatings on electronic packaging substrates are focused to improve heat-dissipation from the device hot spot. Nano porous-based anodic aluminum oxide (AAO) was introduced on Al surfaces aiming to improve heat dissipation. In extension, sealing of nano porous AAO using different deposition method is also introduced for thermal management. In this study, nickel–phosphorous (Ni-P) alloy was sealed and deposited on an already developed nanoporous anodic aluminum oxide (AAO) pattern using an electroless deposition method. The AAO is developed on Al5052 alloy using a two-step anodization process and the formation has resulted in 40- to 55-nm pore diameter and 6–7-μm thickness. The performance of Ni-P sealed nanoporous AAO was studied with respect to different deposition times and the characteristics have been studied via field emission scanning electron microscopy, X-ray diffraction, surface roughness profilometry, and thermal transient measurements. The thermal characteristics have been studied via thermal conductivity analyzer and thermal transient measurements. The resulting Ni-P layer has a cauliflower -like morphology with 1.2-μm layer thickness. The structural analysis show a mixture of amorphous and crystalline nature with sharp Ni peaks (111), (200) including the crystallite size as 518 nm. When compared with bare Al substrate, the 2-hr Ni-P sealing on AAO has a significant reduction in total thermal resistance (ΔRth) to 33%, rise in junction temperature (ΔTj) to 29%, and improved bulk thermal conductivity (k) to 41.5%. Results show enhanced properties of Ni-P-sealed AAO composite coating as a feasible option for the electronic packaging substrates.

Rapid and tunable growth of a well-ordered hexagonal nanoporous anodic aluminum oxide (AAO) structure by two-step high-temperature anodization

In this study, we have developed a swift and well-ordered growth of a nanoporous anodic aluminum oxide (AAO) structure using two-step high temperature anodization of the pure aluminum substrate. The pre-anodization surface treatment of the aluminum substrate assisted in the formation of well-organized nanoporous structures. The two-step anodization process was performed in 0.3 mol/L of oxalic acid at 20 °C with 40 and 45 V to obtain tunable pore diameters. The high temperature of the electrolyte solution facilitated the rapid growth of the nanoporous AAO structure. The top surface image of AAO shows a well-ordered nanoporous structure with an average pore diameter of 70 nm at 40 V and 100 nm at 45 V. The SEM cross-sectional view also illustrates the well-ordered nano-channel and the elemental mapping elaborates the presence of aluminum and oxygen. The thickness of the nanoporous AAO structure was determined using SEM for three anodization time spans (20, 24, and 28 h), in which an increasing trend was observed. The fabricated AAO has a higher thickness and a well-ordered nanoporous structure, which shows that it can be used as a template for fabricating nanostructured materials.

Preparation and characterization of a high-efficiency photoelectric detector composed of hexagonal Al2O3/TiO2/TiN/Au nanoporous array

The light sensitivity of a novel TiO2/TiN-nanotubes-based photodetector is improved by coating it with Au nanoparticles. Using a porous aluminum oxide template (PAOT), TiO2/TiN nanotubes were produced. A two-step anodization procedure was used to produce the PAOT using the Ni-imprinting method. Atomic layer deposition and magnetron sputtering were used to deposit the TiO2/TiN layers. X-ray diffraction, scanning electron microscopy, and reflection/absorption optical spectroscopy were used to characterize the PAOT, PAOT/TiO2/TiN, and PAOT/TiO2/TiN/Au. With a pore diameter of 320 nm and an interpore distance of 61 nm, the PAOT exhibits a high-ordered hexagonal nanoporous array. Following the deposition of TiN on the PAOT/TiO2, the bandgap of PAOT/TiO2 reduced from 3.1 to 2.2 eV, indicating increased visible light absorption. The photoresponsivity values for PAOT/TiO2/TiN and PAOT/TiO2/TiN/Au photodetectors are almost the same (453 mA W−1) at 390 nm. Without and with Au coating, the photoresponsivity values at 636 nm are 392 and 438 mA W−1, suggesting a considerable increase in the Vis/NIR range. Moreover, the detectivity values for the photodetector are enhanced after Au coating, in which the detectivity value for photodetectors are 8.74 × 109 and 8.75 × 1012 Jones at 636 nm before and after Au coating, respectively. While the detectivity values are 8.86 × 1012 Jones for both photodetectors at 390 nm. As a result of the hot electrons from the TiN and Au layers, the constructed photodetector has a very high photoelectrical response, making it extremely promising as a broadband photodetector.

Fabrication and characterization of well-ordered PbS nanowires in aluminum oxide template by sulfurization and vacuum injection molding processes

Lead (Pb) nanowire arrays were fabricated with anodic aluminum oxide (AAO) templates of 30, 100 and 300 nm in pore diameters. Through vacuum injection molding process, Pb/AAO composite was obtained, and lead sulfide (PbS) could further be synthesized after exposing to sulfur gas. AAO templates with different pore sizes were fabricated by using pure aluminum in a two-step anodization. Three types of solutions, which are 10 vol% sulfuric acid, 3 wt% oxalic acid and 1 vol% phosphoric acid, were adopted to achieve AAO of various pore sizes. Different sulfurization temperatures and time spans were applied for studying on the formation mechanism of PbS. Finally, the morphology, composition, structure and elements distribution of the as-prepared Pb and PbS nanowires were confirmed through the use of scanning electron microscopy, energy dispersive x-ray spectroscopy, element-mapping, x-ray diffraction and transmission electron microscopy analysis. The results indicated that Pb nanowires were successfully obtained after applying vacuum injection molding process with 50 kgf cm−2 hydraulic pressure, and PbS nano arrays can be formed by sulfurization at 500 °C for 5 h. Furthermore, an optical property, ultraviolet–visible (UV–Vis) absorption, was also measured. The measurement of the PbS nanowires showed that a significant quantum confinement effect made the energy gap produce a blue shift from 0.41 eV to 1.65 eV or 1.72 eV.

Characterization of the anodic oxide layer deposited on severely deformed and aged AA6063 aluminum alloy

The aim of this study was to investigate the effects of severe plastic deformation (SPD) and thermal treatment on the nanostructure and properties of the anodic oxide layer of AA6063. SPD was conducted using up to 6 passes of equal channel angular pressing (ECAP) which was followed by post-deformation aging treatment. Two-step anodization via hybrid pulse voltage was utilized to form highly ordered anodic coatings. Positive pulse and reverse pulse modes were used for the first and second steps of anodization, respectively. Nanostructure, uniformity, porosity, roughness, micro hardness and brightness of the anodic oxide layers were investigated. It was found that with increasing deformation, the size of intermetallic particles decreased which improved the order and uniformity of the Al2O3 layer. This was attributed to increasing micro- and nano-scale orders of anodic structure. The micro-scale order of anodic structure increases due to high density of grain boundaries after SPD. With increasing deformation, two-dimensional ordering in micro and nano-scales was observed. In addition, micro hardness and brightness of coatings were increased and the roughness and porosity were decreased. This may be due to the fact that a more uniform current can establish between anode and cathode during anodization of samples with more significant deformation which leads to uniform and highly ordered anodic layers. In addition, application of aging treatment leads to higher non-uniformity in established current and causes reduced ordering and uniformity of anodic layer in addition to enhanced roughness and porosity and reduction in brightness.

Enhanced photoelectrochemical performance of NiO-doped TiO2 nanotubes prepared by an impregnation–calcination method

To improve the photocatalytic activity of TiO2, a series of NiO–TiO2 nanotubes (NTbs) is prepared by impregnating TiO2 nanotubes in a solution of NiCl2·6H2O at different concentrations. Self-organized TiO2 nanotubes are prepared by a two-step anodization process. Scanning electron microscopy images show that large particle agglomerates are formed for higher precursor concentrations, and X-ray energy-dispersive spectroscopy results indicate that the atomic percentages of Ni in the NiO–TiO2 NTbs prepared with precursor concentrations of 100 and 300 mM are 1.95% and 4.23%, respectively. Electronic lifetime measurements show that the recombination rate of photogenerated electron–hole pairs is lower for NiO–TiO2 NTbs compared to that of TiO2. Specifically, the recombination rate of the sample prepared at 50 mM is the lowest, which is associated with the longest electron lifetime. Compared to unmodified TiO2 nanotubes, NiO–TiO2 NTbs exhibit improved results for the photocatalytic degradation of rhodamine B.

Performance Enhancement of Actual Wastewater Treatment and Electricity Generation Through Surface Modified TiO₂ Nanotube Arrays Based Photoanode Photocatalytic Fuel Cell.

Herein, we report a surface modified TiO₂ nanowire arrays (NAs) photoanode based photocatalytic fuel cell (PFC) towards simultaneous enhancement of actual wastewater treatment and electricity generation under visible light irradiation. TiO₂ NAs were facile fabricated via two-step anodization process in ethylene glycol and glycerin solution, respectively. Actual wastewater samples were directly applied to evaluate the PFC performance in terms of wastewater degradation and electricity generation through the as-prepared TiO₂ NAs photoanode without loading noble-metals or semiconductors. TiO₂ NAs photoanode prepared from ethylene glycol solution demonstrated a highly ordered surface network, exhibiting short-circuit current density and fill factor nearly 4.3 times and 1.4 times higher than pristine TiO₂ NAs photoanode prepared according to previous reports. The experimental results revealed that the fabrication of TiO₂ NAs by a facile surface modification in ethylene glycol solution can be considered a low-cost and scalable routine for enhancing performance of PFC photoanode towards efficient actual wastewater treatment and electricity generation.

TiO2 Nanotubes Synthesis with Dominant {001} Exposed Facets for Efficient Photocatalytic and Photoelectrochemical Water Oxidation Applications

The photoreactivity of TiO2 nanotube arrays (TiNT) is mainly related to the light absorption and photogenerated charge carriers separation efficiencies. Recently, engineering of the crystal facets has gained increasing attention because of its exceptional ability to extend the photoresponse toward visible light and to separate photogenerated charges. Here, TiNT with high crystallinity and percentage of exposed {001} facets was synthesized using a two-step anodization process in ethylene glycol based electrolyte containing 2 wt% of water and 0.27 M NH4F. Decreasing the potential of the second anodization (from 50 to 20 V) resulted in an increase in crystallinity, crystallite size, and percentage of exposed {001} facets. Because trap states limit the photoreactivity performance of TiNT by facilitating the recombination of photogenerated electron/hole pairs, correlation between crystallinity, preferential crystalline orientation, gap states characteristics (density and location), and photoreactivity performance was investigated. TiNT with a high percentage of {001} exposed facets, consisting mainly of shallow gap states with low density, significantly improve photoelectrochemical water oxidation and photocatalytic efficiencies.

Surface Modification of Nanoporous Anodic Alumina during Self-Catalytic Atomic Layer Deposition of Silicon Dioxide from (3-Aminopropyl)Triethoxysilane.

Changes associated to atomic layer deposition (ALD) of SiO2 from 3-aminopropyl triethoxysilane (APTES) and O3, on a nanoporous alumina structure, obtained by two-step electrochemical anodization in oxalic acid electrolyte (Ox sample) are analysed. A reduction of 16% in pore size for the Ox sample, used as support, was determined by SEM analysis after its coverage by a SiO2 layer (Ox+SiO2 sample), independently of APTES or O3 modification (Ox+SiO2/APTES and Ox+SiO2/APTES/O3 samples). Chemical surface modification was determined by X-ray photoelectron spectroscopy (XPS) technique during the different stages of the ALD process, and differences induced at the surface level on the Ox nanoporous alumina substrate seem to affect interfacial effects of both samples when they are in contact with an electrolyte solution according to electrochemical impedance spectroscopy (EIS) measurements, or their refraction index as determined by spectroscopic ellipsometry (SE) technique. However, no substantial differences in properties related to the nanoporous structure of anodic alumina (photoluminescent (PL) character or geometrical parameters) were observed between Ox+SiO2/APTES and Ox+SiO2/APTES/O3 samples.

Preparation of hexagonal nanoporous Al2O3/TiO2/TiN as a novel photodetector with high efficiency

The unique optical properties of metal nitrides enhance many photoelectrical applications. In this work, a novel photodetector based on TiO2/TiN nanotubes was deposited on a porous aluminum oxide template (PAOT) for light power intensity and wavelength detection. The PAOT was fabricated by the Ni-imprinting technique through a two-step anodization method. The TiO2/TiN layers were deposited by using atomic layer deposition and magnetron sputtering, respectively. The PAOT and PAOT/TiO2/TiN were characterized by several techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive X-ray (EDX). The PAOT has high-ordered hexagonal nanopores with dimensions ~ 320 nm pore diameter and ~ 61 nm interpore distance. The bandgap of PAOT/TiO2 decreased from 3.1 to 2.2 eV with enhancing absorption of visible light after deposition of TiN on the PAOT/TiO2. The PAOT/TiO2/TiN as photodetector has a responsivity (R) and detectivity (D) of 450 mAW-1 and 8.0 × 1012 Jones, respectively. Moreover, the external quantum efficiency (EQE) was 9.64% at 62.5 mW.cm−2 and 400 nm. Hence, the fabricated photodetector (PD) has a very high photoelectrical response due to hot electrons from the TiN layer, which makes it very hopeful as a broadband photodetector.

Self-Ordering of Porous Anodic Alumina Fabricated by Anodizing in Chromic Acid at High Temperature

Anodizing Al in chromic acid is a very useful surface finishing process for corrosion protection and nanoscale porous structure fabrication, whereas the self-ordering of porous anodic alumina (PAA) in chromic acid has never been found to date. Herein, we provide a self-ordered PAA film possessing numerous sub100-nm-scale characteristic bumps through anodizing in chromic acid at high temperature. Anodizing of high purity Al plates in a 0.3 M chromic acid solution at conventional low temperatures, such as 293 K, leads to the formation of a disordered PAA film, whereas anodizing at a high temperature of 348 K causes the self-ordering behavior of the pore structure. The PAA film grown in the initial stage possessed the highest regularity, and it decreased with anodizing time due to pore branching during anodizing. A highly ordered PAA film measuring approximately 340 nm in interpore distance can be fabricated by short-term, two-step anodizing in chromic acid at 348 K and 120 V. The ordered PAA film possesses a characteristic nanostructure consisting of hexagonally arranged 100-nm-scale pores and sub100-nm-scale disordered bumps on their pore walls without any electrolyte chromate anion.

Enhanced bioactivity and antibacterial properties of anodized ZrO2 implant coatings via optimized nanoscale morphology and timed antibiotic release through PLGA overcoat

Surface modification of Zirconium (Zr) with Zirconia (ZrO2) nanotubes (NTs) was performed using a two-step electrochemical anodization to investigate the role of such a modified surface in apatite formation and the inhibition of bacterial growth on Zr implants. Pore size at the surface of the NT arrays was controlled, along with the NT length, by varying the 2nd-step anodizing time duration. Nearly four-fold changes in the pore size were achieved by varying the anodization at the second anodizing step. The apatite formation on the implant surfaces plays an important role in the osteointegration process, which can be greatly influenced by the morphology and crystalline structure of the surface. XRD analysis of the anodized surfaces identified a mixed phase of monoclinic and tetragonal ZrO2 NTs with the crystallite size decreasing with increased 2nd anodizing time duration. Surface roughness of the ZrO2 NTs decreased with an increase in anodizing time duration. The ZrO2 NTs with the largest pore sizes, and the smallest crystallite sizes (ZrO2-15 m) favoured the deposition of a Ca-rich compound on their surfaces following 24 days of soaking in SBF, and showed the highest apatite-forming ability among all studied samples. Antibacterial tests showed that the ZrO2-15 m sample exhibited antibacterial properties with 1log10 CFU/mL reduction of S. aureus and E. coli incubated in a buffer solution for 4 h. Loading the NT layer with antibacterial drug led to a complete inhibition of both bacterial species. The rate of drug release was slowed down by dip coating the drug loaded NTs in a PLGA solution. A higher number of dip-coating steps not only slowed down the release of the drug, it also led to a higher suppression of growth in both bacteria. Longer antibiotic exposure and optimized dosage of the drug released from ZrO2 NTs can therefore be managed by modifying the NT morphology and the number of PLGA dip-coating steps.

Enhanced photocatalytic activity of glyphosate over a combination strategy of GQDs/TNAs heterojunction composites

A photocatalytic process was used to effectively remove glyphosate, an emerging pollutant and contaminant, through advanced oxidation. For this purpose, a feasible combination strategy of two-step anodisation and electrodeposition methods were proposed to fabricate graphene quantum dots (GQDs) supported titanium dioxide nanotube arrays (TNAs). The resultant GQDs/TNAs heterojunction composite exhibited significant degradation reactivity and circulation stability for glyphosate due to its excellent photo-generated electron and hole separation ability. After the introduction of GQDs into TNAs, the photodegradation efficiency of glyphosate increased from 69.5% to 94.7% within 60 min under UV–Vis light irradiation (λ = 320–780 nm). By analysing the intermediate products and through the evolvement of heteroatoms during glyphosate photodegradation, alanine and serine were discovered for the first time, and a detailed degradation mechanism of glyphosate was proposed. This study indicates that GQDs/TNAs heterojunction composite can almost completely degrade the glyphosate into inorganics under the appropriate conditions.

Decoration of TiO2 nanoparticles on TiO2 microcone array with holes as photoanodes of fiber-shaped dye-sensitized solar cells

Fiber-shaped dye-sensitized solar cell (FDSC) is one of efficient energy generation devices for soft electronics, owing to low-cost and dim-light operable features. The key component of FDSC is photoanode, which is responsible for absorbing incident light and generating charges. Designing TiO2 structure is significant for fabricating efficient photoanode of FDSC. In this study, it is the first time to fabricate TiO2 nanoparticle-decorated TiO2 microcone array (TMC) with holes using simple two-step anodization and dip-coating processes as semiconductor on photoanode of FDSC. Different H2SO4 concentrations is used to creating holes on TMC. Holes are generated on TMC in anodization process, but TMC are detached from Ti wire more seriously when higher H2SO4 concentration is used. The optimized photoanode of FDSC is prepared using 30 mM H2SO4. The optimized FDSC shows solar-to-electricity conversion efficiency (η) of 2.52%, while the FDSC with the pure TMC photoanode only shows η of 1.68%. The better photovoltaic performance of FDSC comprising TiO2 nanoparticle-decorated TMC with holes photoanode is owing to abundant contacts between TMC and TiO2 nanoparticles and high surface area of TiO2 nanoparticles for dye adsorption. The highest collection efficiency of 92.21% is also achieved for the FDSC with the optimized photoanode, analyzed using intensity modulated photocurrent/voltage spectroscopy spectra.

A high-and-rapid-response capacitive humidity sensor of nanoporous anodic alumina by one-step anodizing commercial 1050 aluminum alloy and its enhancement mechanism

Anodic aluminum oxide (AAO) is a well-known nanoporous material and a template for nanotechnology application. The AAO based humidity sensor is traditionally fabricated using low-temperature (0–10 °C) two-step anodization in oxalic acid at 40 V from the expensive high-purity aluminum of small-area as well with low response and low intensity. Here, one-step anodizing commercial large-area low-purity aluminum 1050 alloy was realized for high-performance humidity sensor by hybrid-pulse anodization in 0.3 M oxalic acid at 20 V at 25 °C that merits low cost, short fabrication time and high-and-rapid capacitive response. The performance enhancement is attributed to the increased total pore area adsorption ratio and the electrode area of AAO with lower thickness to make much more water vapor molecules adsorb onto the wall surface of pores for sensing with high capacitance, response and short response-recovery time. The low-thickness pores make water molecules adsorb onto and desorb from the pores surface more quickly because of shorter diffusion path. Also, a small-area sample of traditional 40 V AAO is used as a reference for comparison. A shorter anodization time of 55 min is also fabricated for understanding the thickness effect on the response-recovery time. The large-area AAO humidity sensor of 16 cm2 at 20 V exhibits high response (above 5000 %, 3.5 times the traditional reference) and quick response-recovery time (9 s). The high-and-rapid-response enhancement mechanism of AAO capacitive humidity sensor is established.

Inorganic Thermoelectric Fibers: A Review of Materials, Fabrication Methods, and Applications.

Thermoelectric technology can directly harvest the waste heat into electricity, which is a promising field of green and sustainable energy. In this aspect, flexible thermoelectrics (FTE) such as wearable fabrics, smart biosensing, and biomedical electronics offer a variety of applications. Since the nanofibers are one of the important constructions of FTE, inorganic thermoelectric fibers are focused on here due to their excellent thermoelectric performance and acceptable flexibility. Additionally, measurement and microstructure characterizations for various thermoelectric fibers (Bi-Sb-Te, Ag2Te, PbTe, SnSe and NaCo2O4) made by different fabrication methods, such as electrospinning, two-step anodization process, solution-phase deposition method, focused ion beam, and self-heated 3ω method, are detailed. This review further illustrates that some techniques, such as thermal drawing method, result in high performance of fiber-based thermoelectric properties, which can emerge in wearable devices and smart electronics in the near future.

Fabrication and characterization of the hierarchical AAO film and AAO-MnO2 composite as the anode foil of aluminum electrolytic capacitor

Anodic aluminum oxide (AAO) film of different regular hierarchical pore structures and AAO-MnO 2 composite of many homogeneously distributed microvoids have been prepared and comparatively characterized, mostly as they were adopted as an anode foil of aluminum electrolytic capacitors. Results showed that the hierarchical pore structure of AAO film is composed of a supernatant layer of larger holes and a rock-bottom layer of smaller holes. The smaller holes' density increases with the reduction of the secondary anodization voltage in the two-step anodization process of the AAO film, which subsequently enlarges the specific capacitance to 7.88 μF/cm 2 and may also increase the leakage current when the AAO film is adopted as the anode foil in an aluminum electrolytic capacitor. The obtained hierarchical AAO-MnO 2 composite, with a multi-layered interweaved structure, has not only significantly brought up the specific capacitance from 7.88 μF/cm 2 to 25.56 μF/cm 2 but also may significantly reduce the leakage current and consequently improve the stability when being used as the anode foil. Compared with merely increasing the surface area of AAO film, the introduction of high dielectric constant compounds into the AAO film without changing the actual surface area can improve the aluminum electrolytic capacitor's capacitance performance more effectively. • The specific capacitance can be 19.15 uF/cm 2 when hierarchical AAO film used in medium aluminum electrolytic capacitor. • An improved method was used to introduce MnO2 into porous AAO film without reducing the real surface area significantly. • The capacitance can be 25.56 uF/cm 2 when AAO-MnO 2 composite used in the medium voltage aluminum electrolytic capacitors.

Antimicrobial properties and corrosion behavior of TiO2[sbnd]NTs electrodes modified with Ag and ZnO nanorod in simulated body fluid solution

The synthesis of Ag nanoparticles (NPs) on titanium dioxide nanotubes (TiO2NTs) was synthesized via chemical reduction technique. In addition, ZnO nanorods were deposited on TiO2NTs via hydrothermal method. First of all, TiO2NTs were produced by the two-step anodization method. The antibacterial/antifungal activity of the prepared materials was investigated in biological applications. Moreover, Ti-based nanostructures have been extensively used as an implant material. For this purpose, the corrosion behavior of the fabricated materials was examined in the simulated body fluid (SBF) solution by electrochemical techniques. Morphological and structural analysis of the materials was studied with field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) method. FE-SEM images showed that well-ordered top-open TiO2 nanotubes with pore diameter of around 85.29 ± 6.09 nm and tube length of about 20.49 ± 0.33 μm were formed. Furthermore, micro hardness and contact angle tests were performed. From electrochemical impedance spectroscopy (EIS) results, the highest resistance value of ZnO-TiO2NTs at exposure of 7th days showed that ZnO nanorods provide an important protection against corrosion by blocking the tube channels of TiO2NTs. Furthermore, ZnO-TiO2NTs showed antifungal activity, while Ag-TiO2NTs exhibited antibacterial activity.

Erratum to: Effects of Two-Step Anodization on Surface Wettability in Surface Treatment of Aluminum Alloy

Erratum to: Effects of Two-Step Anodization on Surface Wettability in Surface Treatment of Aluminum Alloy