The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform
Ryosuke O. Suzuki - One of the best experts on this subject based on the ideXlab platform.
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Optimum Exploration for the Self-Ordering of Anodic Porous Alumina Formed via Selenic Acid Anodizing
Journal of The Electrochemical Society, 2015Co-Authors: Shunta Akiya, Shungo Natsui, Tatsuya Kikuchi, Ryosuke O. SuzukiAbstract:Improvements of the regularity of the arrangement of anodic porous alumina formed by Selenic Acid anodizing were investigated under various operating conditions. The oxide burning voltage increased with the stirring rate of the Selenic Acid solution, and the high applied voltage without oxide burning was achieved by vigorously stirring the solution. The regularity of the porous alumina was improved as the anodizing time and surface flatness increased. Conversely, the purity of the 99.5–99.9999 wt% aluminum specimens without second phases of metals and metallic compounds was not affected by the regularity of the porous alumina formed by Selenic Acid anodizing. The porous alumina was also self-ordered on/around a defect, such as a grain boundary, under self-ordering high voltage anodizing conditions. A highly ordered cell arrangement measuring 111 nm in diameter was successfully fabricated over the whole aluminum surface by Selenic Acid anodizing using a 99.999 wt% aluminum plate at 273 K and 46 V for 24 h under vigorous stirring conditions
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self ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:Abstract The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H 2 SeO 4 ) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step.
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Self-ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H2SeO4) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step. © 2014 Elsevier Ltd.
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Rapid fabrication of self-ordered porous alumina with 10-/sub-10-nm-scale nanostructures by Selenic Acid anodizing
Scientific Reports, 2013Co-Authors: Osamu Nishinaga, Shungo Natsui, Tatsuya Kikuchi, Ryosuke O. SuzukiAbstract:Anodic porous alumina has been widely investigated and used as a nanostructure template in various nanoapplications. The porous structure consists of numerous hexagonal cells perpendicular to the aluminum substrate and each cell has several tens or hundreds of nanoscale pores at its center. Because the nanomorphology of anodic porous alumina is limited by the electrolyte during anodizing, the discovery of additional electrolytes would expand the applicability of porous alumina. In this study, we report a new self-ordered nanoporous alumina formed by Selenic Acid (H2SeO4) anodizing. By optimizing the anodizing conditions, anodic alumina possessing 10-nm-scale pores was rapidly assembled (within 1 h) during Selenic Acid anodizing without any special electrochemical equipment. Novel sub-10-nm-scale spacing can also be achieved by Selenic Acid anodizing and metal sputter deposition. Our new nanoporous alumina can be used as a nanotemplate for various nanostructures in 10-/sub-10-nm-scale manufacturing.
Tatsuya Kikuchi - One of the best experts on this subject based on the ideXlab platform.
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Optimum Exploration for the Self-Ordering of Anodic Porous Alumina Formed via Selenic Acid Anodizing
Journal of The Electrochemical Society, 2015Co-Authors: Shunta Akiya, Shungo Natsui, Tatsuya Kikuchi, Ryosuke O. SuzukiAbstract:Improvements of the regularity of the arrangement of anodic porous alumina formed by Selenic Acid anodizing were investigated under various operating conditions. The oxide burning voltage increased with the stirring rate of the Selenic Acid solution, and the high applied voltage without oxide burning was achieved by vigorously stirring the solution. The regularity of the porous alumina was improved as the anodizing time and surface flatness increased. Conversely, the purity of the 99.5–99.9999 wt% aluminum specimens without second phases of metals and metallic compounds was not affected by the regularity of the porous alumina formed by Selenic Acid anodizing. The porous alumina was also self-ordered on/around a defect, such as a grain boundary, under self-ordering high voltage anodizing conditions. A highly ordered cell arrangement measuring 111 nm in diameter was successfully fabricated over the whole aluminum surface by Selenic Acid anodizing using a 99.999 wt% aluminum plate at 273 K and 46 V for 24 h under vigorous stirring conditions
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self ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:Abstract The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H 2 SeO 4 ) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step.
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Self-ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H2SeO4) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step. © 2014 Elsevier Ltd.
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Rapid fabrication of self-ordered porous alumina with 10-/sub-10-nm-scale nanostructures by Selenic Acid anodizing
Scientific Reports, 2013Co-Authors: Osamu Nishinaga, Shungo Natsui, Tatsuya Kikuchi, Ryosuke O. SuzukiAbstract:Anodic porous alumina has been widely investigated and used as a nanostructure template in various nanoapplications. The porous structure consists of numerous hexagonal cells perpendicular to the aluminum substrate and each cell has several tens or hundreds of nanoscale pores at its center. Because the nanomorphology of anodic porous alumina is limited by the electrolyte during anodizing, the discovery of additional electrolytes would expand the applicability of porous alumina. In this study, we report a new self-ordered nanoporous alumina formed by Selenic Acid (H2SeO4) anodizing. By optimizing the anodizing conditions, anodic alumina possessing 10-nm-scale pores was rapidly assembled (within 1 h) during Selenic Acid anodizing without any special electrochemical equipment. Novel sub-10-nm-scale spacing can also be achieved by Selenic Acid anodizing and metal sputter deposition. Our new nanoporous alumina can be used as a nanotemplate for various nanostructures in 10-/sub-10-nm-scale manufacturing.
Osamu Nishinaga - One of the best experts on this subject based on the ideXlab platform.
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self ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:Abstract The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H 2 SeO 4 ) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step.
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Self-ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H2SeO4) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step. © 2014 Elsevier Ltd.
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Rapid fabrication of self-ordered porous alumina with 10-/sub-10-nm-scale nanostructures by Selenic Acid anodizing
Scientific Reports, 2013Co-Authors: Osamu Nishinaga, Shungo Natsui, Tatsuya Kikuchi, Ryosuke O. SuzukiAbstract:Anodic porous alumina has been widely investigated and used as a nanostructure template in various nanoapplications. The porous structure consists of numerous hexagonal cells perpendicular to the aluminum substrate and each cell has several tens or hundreds of nanoscale pores at its center. Because the nanomorphology of anodic porous alumina is limited by the electrolyte during anodizing, the discovery of additional electrolytes would expand the applicability of porous alumina. In this study, we report a new self-ordered nanoporous alumina formed by Selenic Acid (H2SeO4) anodizing. By optimizing the anodizing conditions, anodic alumina possessing 10-nm-scale pores was rapidly assembled (within 1 h) during Selenic Acid anodizing without any special electrochemical equipment. Novel sub-10-nm-scale spacing can also be achieved by Selenic Acid anodizing and metal sputter deposition. Our new nanoporous alumina can be used as a nanotemplate for various nanostructures in 10-/sub-10-nm-scale manufacturing.
Kurt J Irgolic - One of the best experts on this subject based on the ideXlab platform.
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Determination of selenium compounds by HPLC with ICP-MS or FAAS as selenium-specific detector.
Chinese Journal of Chromatography, 1999Co-Authors: Fangshi Li, Walter Goessler, Kurt J IrgolicAbstract:Abstract A speciation method was developed for selenious Acid, Selenic Acid, trimethylselenonium ion (TMSe) and selenomethionine (SeMet). Separation of the four selenium species was achieved by HPLC on an ESA Anion III anion-exchange column using aqueous mobile phase of 5.5 mmol/L ammonium citrate at pH 5.5 with a flow rate of 1.5 mL/min. Under the optimal conditions, the four selenium species were separated within 8 minutes. On-line selenium-specific detection was carried out with an inductively coupled plasma mass spectrometer (ICP-MS) or a flame atomic absorption spectrometer (FAAS). The detection limits of HPLC-FAAS were approximately rho(Se) = 1 mg/L for each compound (100 microL injection). To increase the nebulization efficiency of the ICP-MS, the Meinhard concentric nebulizer was replaced by an ultrasonic nebulizer (USN). The ICP-MS signal intensity was increased by a factor of 7 for selenious Acid and 24 to 31 for TMSe, SeMet and Selenic Acid with the USN compared to that with the Meinhard nebulizer. The detection limits of the HPLC-USN-ICP-MS were rho(Se) = 0.08 microgram/L for TMSe, rho(Se) = 0.34 microgram/L for selenious Acid, rho(Se) = 0.18 microgram/L for SeMet and rho(Se) = 0.07 microgram/L for Selenic Acid.
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determination of trimethylselenonium iodide selenomethionine selenious Acid and Selenic Acid using high performance liquid chromatography with on line detection by inductively coupled plasma mass spectrometry or flame atomic absorption spectrometry
Journal of Chromatography A, 1999Co-Authors: Fangshi Li, Walter Goessler, Kurt J IrgolicAbstract:Abstract An analytical method has been developed for the determination of selenious Acid, Selenic Acid, trimethylselenonium ion, and selenomethionine. The four selenium compounds were separated by HPLC on a column (25 cm×4 mm I.D.) of the anion-exchanger ESA Anion III with a mobile phase (1.5 ml/min) of 0.0055 M ammonium citrate (pH 5.5). Detection was carried out using an on-line inductively coupled plasma mass spectrometer (ICP-MS) or a flame atomic absorption spectrometer (FAAS) as the selenium-specific detector. The chromatographic parameters and the chemical factors affecting the separation of the selenium species were optimized. The four selenium compounds could be separated within 8 minutes. The detection limits of the coupled HPLC–FAAS system were approximately 1 mg Se/l for each compound (100 μl injection), estimated as three times the base-line noise of the chromatograms. More powerful selenium detection was achieved with an ICP-MS. Selenium was measured at m/z 78. To increase the nebulization efficiency, the Meinhard concentric glass nebulizer was replaced by an ultrasonic nebulizer. The ICP-MS signal intensity was increased with the ultrasonic nebulization by a factor of 7 times for selenious Acid and 24 to 31 times for trimethylselenonium ion, selenomethionine, and Selenic Acid compared to that with the Meinhard nebulization. The detection limits achieved by the HPLC–ICP-MS with the ultrasonic nebulization were 0.08 μg Se/l for trimethylselenonium ion, 0.34 μg Se/l for selenious Acid, 0.18 μg Se/l for selenomethionine, and 0.07 μg Se/l for Selenic Acid, respectively.
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Retention Behavior of Inorganic and Organic Selenium Compounds on a Polymer-Based Cation Exchange Column
Phosphorus Sulfur and Silicon and The Related Elements, 1998Co-Authors: Tadesse Wondimu, Walter Goessler, Mulat Abegaz, Gary Banuelos, Kurt J IrgolicAbstract:The retention behavior of selenous Acid, Selenic Acid, selenomethionine, selenoethionine, selenocystine, selenohomocystine, trimethyl-selenonium iodide, and (3-amino-3-carboxy-1-propyl)-dimethylselenonium iodide was studied on the polymer-based PRP-X200 cation exchange column with an aqueous solution of pyridine (20 to 100 mM) in the pH range 1.1-6.0 adjusted with formic Acid as the mobile phase. An inductively coupled plasma mass spectrometer equipped with a hydraulic high pressure nebulizer served as selenium specific detector. The retention behavior was rationalized in terms of the pH-dependent deprotonation of the selenium compounds and of the pyridinium cation and of the formation of ion-pairs between hydrogen selenite, selenate, or the zwitterionic groups of the selenoamino Acids with the pyridinium cation. A good separation of seven selenium compounds was achieved within 5.0 min at 40°C with 20 mM pyridine (pH 3.70). Selenoethionine eluted 15 min after injection. Peak areas and peak heights of the ...
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Behaviour of selenium compounds in FI-HG-AAS
Analytical Communications, 1998Co-Authors: Amit Chatterjee, Kurt J IrgolicAbstract:The borohydride active volatile compound formation potential of twelve selenium compounds [selenous Acid, Selenic Acid, selenocystine (Secys), selenohomocystine (Sehcys), selenomethionine (Semet), selenoethionine (Seet), trimethylselenonium iodide (TmSe), selenocystathionine (Secystha), selenocystamine (Secysta), selenourea (Seur), selenocholine (Sech), and dimethyl(3-amino-3- carboxy-1-propyl)selenonium iodide (DmpSe)] were investigated in a FI-HG system with different sodium borohydride concentrations (0.3% in 0.1% sodium hydroxide, and 0.5, 0.7, and 1.0% in 0.2% sodium hydroxide) in the presence of 3 M hydrochloric Acid using an atomic absorption spectrometer as selenium-specific detector. Percentage recoveries with respect to selenous Acid of Selenic Acid, Secys, Sehcys, Semet, Seet, TmSe, Secystha; Secysta, Seur, Sech, and DmpSe were 0, 10.3, 19.7, 23.5, 32.4, 13.7, 16.5, 16.5, 11.3, 5.6 and 7.7%, respectively in the presence of 0.3% borohydride stabilized with 0.1% sodium hydroxide. By multiplying the borohydride concentrations, percentage recoveries of TmSe, DmpSe, Sech, Sehcys and Secysta were elevated, whereas those of Semet, Seet and Seur were reduced. However, percentage recoveries of Secys and Secystha remained almost uniform within the entire borohydride range. TmSe exhibited a 105% recovery with respect to selenous Acid at 1.0% borohydride concentration, whereas Selenic Acid was inert to borohydride active volatile compound formation.
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Retention behavior of inorganic and organic selenium compounds on a silica-based strong-cation-exchange column with an inductively coupled plasma mass spectrometer as selenium-specific detector
Journal of Chromatography A, 1997Co-Authors: Walter Goessler, Mulat Abegaz, Doris Kuehnelt, Claudia Schlagenhaufen, Kurt Kalcher, Kurt J IrgolicAbstract:Abstract The retention behavior of eight selenium compounds (selenous Acid, Selenic Acid, selenocystine, selenohomocystine, selenomethionine, selenoethionine, trimethylselenonium iodide, and dimethyl(3-amino-3-carboxy-1-propyl)selenonium iodide) with aqueous solutions of pyridine (20 mmol/l) in the pH range 2.0–5.7 on a Supelcosil LC-SCX cation-exchange column was investigated. An inductively coupled plasma mass spectrometer was employed as the selenium-specific detector. To increase the nebulization efficiency, the Meinhard concentric glass nebulizer was replaced by a hydraulic high-pressure nebulizer. At pH 5.0, seven selenium compounds could be separated within 400 s, but selenohomocystine and selenomethionine had the same retention time. Selenomethionine can be separated from selenohomocystine with an aqueous solution of pyridine (20 mmol/l) adjusted with formic Acid to pH 2.0. At 1 ng Se ml−1, the relative standard deviations (n=5) of the signal area for the eight selenium compounds ranged from 7 to 11%, and at 50 ng Se ml−1 from 0.6 to 2.6%.
Shungo Natsui - One of the best experts on this subject based on the ideXlab platform.
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Optimum Exploration for the Self-Ordering of Anodic Porous Alumina Formed via Selenic Acid Anodizing
Journal of The Electrochemical Society, 2015Co-Authors: Shunta Akiya, Shungo Natsui, Tatsuya Kikuchi, Ryosuke O. SuzukiAbstract:Improvements of the regularity of the arrangement of anodic porous alumina formed by Selenic Acid anodizing were investigated under various operating conditions. The oxide burning voltage increased with the stirring rate of the Selenic Acid solution, and the high applied voltage without oxide burning was achieved by vigorously stirring the solution. The regularity of the porous alumina was improved as the anodizing time and surface flatness increased. Conversely, the purity of the 99.5–99.9999 wt% aluminum specimens without second phases of metals and metallic compounds was not affected by the regularity of the porous alumina formed by Selenic Acid anodizing. The porous alumina was also self-ordered on/around a defect, such as a grain boundary, under self-ordering high voltage anodizing conditions. A highly ordered cell arrangement measuring 111 nm in diameter was successfully fabricated over the whole aluminum surface by Selenic Acid anodizing using a 99.999 wt% aluminum plate at 273 K and 46 V for 24 h under vigorous stirring conditions
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self ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:Abstract The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H 2 SeO 4 ) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step.
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Self-ordering behavior of anodic porous alumina via Selenic Acid anodizing
Electrochimica Acta, 2014Co-Authors: Tatsuya Kikuchi, Shungo Natsui, Osamu Nishinaga, Ryosuke O. SuzukiAbstract:The self-ordering behavior of anodic porous alumina that was formed by anodizing in Selenic Acid electrolyte (H2SeO4) at various concentrations and voltages was investigated with SEM and AFM imaging. A high purity aluminum foil was anodized in 0.1-3.0 M Selenic Acid solutions at 273 K and at constant cell voltages in the range of 37 to 51 V. The regularity of the cell arrangement increased with increasing anodizing voltage and Selenic Acid concentration under conditions of steady oxide growth without burning. Anodizing at 42-46 V in 3.0 M Selenic Acid produced highly ordered porous alumina. By selective dissolution of the anodic porous alumina, highly ordered convex nanostructures of aluminum with diameters of 20 nm and heights of 40 nm were exposed at the apexes of each hexagonal dimple array. Highly ordered anodic porous alumina with a cell size of 102 nm from top to bottom can be fabricated by a two-step Selenic Acid anodizing process, that includes the first anodizing step, the selective oxide dissolution, and the second anodizing step. © 2014 Elsevier Ltd.
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Rapid fabrication of self-ordered porous alumina with 10-/sub-10-nm-scale nanostructures by Selenic Acid anodizing
Scientific Reports, 2013Co-Authors: Osamu Nishinaga, Shungo Natsui, Tatsuya Kikuchi, Ryosuke O. SuzukiAbstract:Anodic porous alumina has been widely investigated and used as a nanostructure template in various nanoapplications. The porous structure consists of numerous hexagonal cells perpendicular to the aluminum substrate and each cell has several tens or hundreds of nanoscale pores at its center. Because the nanomorphology of anodic porous alumina is limited by the electrolyte during anodizing, the discovery of additional electrolytes would expand the applicability of porous alumina. In this study, we report a new self-ordered nanoporous alumina formed by Selenic Acid (H2SeO4) anodizing. By optimizing the anodizing conditions, anodic alumina possessing 10-nm-scale pores was rapidly assembled (within 1 h) during Selenic Acid anodizing without any special electrochemical equipment. Novel sub-10-nm-scale spacing can also be achieved by Selenic Acid anodizing and metal sputter deposition. Our new nanoporous alumina can be used as a nanotemplate for various nanostructures in 10-/sub-10-nm-scale manufacturing.
