Brilliant and tunable color by changing pore diameter of metal-coated porous anodic alumina

In this study, the effect of anodizing voltage on the morphology of porous anodic alumina and growth kinetics of anodizing of aluminium manganese alloy was reported. It was found that the increasing anodizing voltage affect the morphology and dimensional parameters of porous AAO. Both pore diameter and interpore distance increased as a function of anodizing voltage. The regularity of porous AAO was affected by anodizing voltage. Dielectric breakdown occurred at anodizing voltage of 70 V and led to protrusions and cracks of the porous anodic alumina. Moderate anodizing voltage promoted the formation of well ordered pore arrangement while disordered pore arrangement was observed when the anodizing voltage was too low or too high. The thickness of porous AAO increased as the anodizing voltage increased.

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Effect of Manganese Content on the Fabrication of Porous Anodic Alumina

Journal of Nanomaterials ◽

10.1155/2012/752926 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

C. H. Voon ◽

M. N. Derman ◽

U. Hashim

Keyword(s):

Pore Diameter ◽

Chromic Acid ◽

Cell Structure ◽

Manganese Content ◽

Single Step ◽

Anodic Alumina ◽

Porous Anodic Alumina ◽

Secondary Phases ◽

Interpore Distance ◽

Ordered Porous

The influence of manganese content on the formation of well-ordered porous anodic alumina was studied. Porous anodic alumina has been produced on aluminium substrate of different manganese content by single-step anodizing at 50 V in 0.3 M oxalic acid at 15°C for 60 minutes. The well-ordered pore and cell structure was revealed by subjecting the porous anodic alumina to oxide dissolution treatment in a mixture of chromic acid and phosphoric acid. It was found that the manganese content above 1 wt% impaired the regularity of the cell and pore structure significantly, which can be attributed to the presence of secondary phases in the starting material with manganese content above 1 wt%. The pore diameter and interpore distance decreased with the addition of manganese into the substrates. The time variation of current density and the thickness of porous anodic alumina also decreased as a function of the manganese content in the substrates.

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Effect of Anodizing Voltage on the Formation of Porous Anodic Alumina on Al-0.5wt% Mn Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.925.455 ◽

2014 ◽

Vol 925 ◽

pp. 455-459 ◽

Cited By ~ 3

Author(s):

Chun Hong Voon ◽

M.N. Derman ◽

U. Hashim ◽

K.L. Foo

Keyword(s):

Pore Diameter ◽

Anodic Alumina ◽

Porous Anodic Alumina ◽

Manganese Alloy ◽

Interpore Distance ◽

Ordered Porous

In this study, the effect of anodizing voltage on the morphologies, pore diameter and interpore distance on the porous anodic alumina formed on aluminium manganese alloy was reported. It was found that the anodizing influenced the morphologies and regularities of porous anodic alumina formed on aluminum-manganese substrate. Well ordered porous anodic alumina was obtained when anodizing voltage were 40 V and 50 V respectively. Disordered porous anodic alumina was formed when anodizing of 30 V and 70 V were applied during the anodizing process. Both pore diameter and interpore distance of porous anodic alumina increased linearly with the anodizing voltage.

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THERMAL STUDIES OF POROUS ALUMINUM OXIDE MEMBRANES

Physical and Chemical Aspects of the Study of Clusters Nanostructures and Nanomaterials ◽

10.26456/pcascnn/2021.13.312 ◽

2021 ◽

pp. 312-319

Author(s):

Екатерина Николаевна Муратова

Keyword(s):

Sulfuric Acid ◽

Pore Diameter ◽

Structural Parameters ◽

Thermal Studies ◽

Small Diameter ◽

Anodic Alumina ◽

Porous Anodic Alumina ◽

Ir Radiation ◽

Alumina Membranes ◽

D 20

Изучение оптических свойств наноразмерных мембран пористого анодного оксида алюминия позволяет значительно расширить области применения данного материала. В работе представлены результаты тепловизионных исследований мембран пористого анодного оксида алюминия с различными структурными параметрами. Построены профили распределения температуры для мембран, полученных в различных электролитах на основе серной, щавелевой и ортофосфорной кислотах. Установлено, что экранирование ИК излучения сильнее (примерно на 30%) проявляется у мембран с меньшим диаметром пор d ≈ 20 нм по сравнению с мембранами, у которых d ≈ 200 нм. Это связано с рассеиванием теплового излучения на неоднородностях структуры, которых значительно больше в мембранах пористого анодного оксида алюминия, полученных на серной кислоте. В качестве источников неоднородности выступают поры малого диаметра, недотравленные области и дефекты. Также, за счет повышенной активности серной кислоты по сравнению с другими используемыми кислотами большее количество анионов встраивается в структуру образца. Study of optical properties of nanoscale membranes of porous anodic alumina can significantly expand the scope of this material. The paper presents the results of thermal imaging studies of porous anodic alumina membranes with various structural parameters. Temperature distribution profiles for membranes obtained in various electrolytes based on sulfuric, oxalic and orthophosphoric acids have been constructed. It was found that the shielding of IR radiation is more pronounced (approximately 30 %) in membranes with a smaller pore diameter d ≈ 20 nm compared to membranes with a larger pore diameter d ≈ 200 nm. This is due to the scattering of thermal radiation on structural inhomogeneities, which are much higher in porous anodic alumina membranes obtained with sulfuric acid. Small-diameter pores, under-etched areas and defects act as sources of inhomogeneity. Also, due to the increased activity of sulfuric acid in comparison with other acids used, more anions are incorporated into the structure of the sample.

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