The Metallurgy of Anodizing Aluminum

Runge, Jude Mary

doi:10.1007/978-3-319-72177-4

Cited by 61 publications

(85 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The method used for the fabrication of silver nanosphere arrays decorated on a polycarbonate substrate with self-organized, hexagonal close-packed nanocone is illustrated schematically in Figure 1. First, a nanocone-shaped groove array structure of aluminum substrate was fabricated by using anodic aluminum self-assembly technique [18][19][20]. To form a cone-shaped cavity, the anodization and pore widening processes were alternately repeated several times, which creates a top widened and bottom narrow holes, the diameter of these holes are reduced gradually from the top to the bottom of these holes.…”

Section: Methodsmentioning

confidence: 99%

Tunable Silver Nanoparticle Arrays by Hot Embossing and Sputter Deposition for Surface-Enhanced Raman Scattering

Huang

Tsai

2019

Applied Sciences

View full text Add to dashboard Cite

Surface-enhanced Raman scattering (SERS) spectroscopy has attracted a lot of attention over the past 30 years. Due to its extreme sensitivity and label-free detection capability, it has shown great potential in areas such as analytical chemistry, biochemistry, and environmental science. However, the major challenge is to manufacture large-scale highly SERS active substrates with high controllability, good reproducibility, and low cost. In this study, we report a novel method to fabricate uniform silver nanoparticle arrays with tunable particle sizes and interparticle gaps. Using hot embossing and sputtering techniques, we were able to batch produce the silver nanoparticle arrays SERS active substrate with consistent quality and low cost. We showed that the proposed SERS active substrate has good uniformity and high reproducibility. Experimental results show that the SERS enhancement factor is affected by silver nanoparticles size and interparticle gaps. Furthermore, the enhancement factor of the SERS signal obtained from Rhodamine 6G (R6G) probe molecules was as high as 1.12 × 107. Therefore, the developed method is very promising for use in many SERS applications.

show abstract

Section: Methodsmentioning

confidence: 99%

Tunable Silver Nanoparticle Arrays by Hot Embossing and Sputter Deposition for Surface-Enhanced Raman Scattering

Huang

Tsai

2019

Applied Sciences

View full text Add to dashboard Cite

show abstract

“…However, a recent publication by Etienne et al [271] reports some information on the local pH evolution with time 10 to 20 µm above anodized aluminum surfaces in selected sealing solutions in which local pH measurements in the first 2 to 5 minutes manifested increase in pH by initial bulk pHs of 3.4 and 4.6 the measured pH maxima were ≈5.5 and >5.5 respectively but decreased to values tending towards the initial bulk values during 20 min. Runge [272] had highlighted the existence of a pH profile across the depth of anodic oxide layer with pH increasing with depth during anodization. The existence of a pH gradient inside the nano-confined space(s) of the nanopores of the anodic oxide layer during sealing is very likely to exert influences on the mechanism and/or kinetics of the sealing process.…”

Section: Ph Inside the Pores And Its Effectsmentioning

confidence: 99%

The Sealing Step in Aluminum Anodizing: A Focus on Sustainable Strategies for Enhancing Both Energy Efficiency and Corrosion Resistance

2020

View full text Add to dashboard Cite

Increasing demands for environmental accountability and energy efficiency in industrial practice necessitates significant modification(s) of existing technologies and development of new ones to meet the stringent sustainability demands of the future. Generally, development of required new technologies and appropriate modifications of existing ones need to be premised on in-depth appreciation of existing technologies, their limitations, and desired ideal products or processes. In the light of these, published literature mostly in the past 30 years on the sealing process; the second highest energy consuming step in aluminum anodization and a step with significant environmental impacts has been critical reviewed in this systematic review. Emphasis have been placed on the need to reduce both the energy input in the anodization process and environmental implications. The implications of the nano-porous structure of the anodic oxide on mass transport and chemical reactivity of relevant species during the sealing process is highlighted with a focus on exploiting these peculiarities, in improving the quality of sealed products. In addition, perspective is provided on plausible approaches and important factors to be considered in developing sealing procedures that can minimize the energy input and environmental impact of the sealing step, and ensure a more sustainable aluminum anodization process/industry.Coatings 2020, 10, 226 2 of 55 sealing methods. Furthermore, the applicability of another hitherto popular sealing process; chromate sealing, is currently limited to essential parts in the aerospace industry due to toxicological, health, and environmental implications traced to Cr(VI) employed in the process [7][8][9][10][11][12][13][14][15][16]. On the other hand, the advantages of another industrially utilized sealing process; the nickel fluoride (cold) sealing process is limited by the toxicity of nickel salts which narrows its range of application, and introduces added costs due to post-sealing wastewater treatments and management [17][18][19][20]. Further efforts at sealing anodized aluminum at temperatures lower than that used in hydrothermal (high temperature) sealing, have led to much variety in the chemical constitution and operating temperatures of sealing baths [21]. On the basis of temperature at which the sealing step is carried out, sealing can be classified into three major categories; high temperature, mid-temperature, and room-temperature or cold sealing. In this work sealing at temperatures from 0 to 40 • C is classified as low temperature sealing, from ≥ 40 • C to 70 • C as intermediate or mid temperature sealing, and sealing at temperatures > 70 • C as high temperature sealing.

show abstract

“…The manufacturing process is schematically illustrated in Figure 1 . First, the structure of the aluminum substrate with a nano-conical cavity array was fabricated by using anodized aluminum self-assembly technology [ 25 , 26 , 27 ]. The manufacturing procedure of the nano-cone hole array on the aluminum substrate included electrolytic polishing, anodization, and anodized aluminum removal.…”

Section: Methodsmentioning

confidence: 99%

Integrated EC-SERS Chip with Uniform Nanostructured EC-SERS Active Working Electrode for Rapid Detection of Uric Acid

Huang

Hsiao

2020

Sensors

View full text Add to dashboard Cite

Toxemia of pregnancy is a very dangerous disease for pregnant women. The mortality rate of toxemia of pregnancy is close to 10% to 15%. Early detection of pregnancy toxemia is to monitoring uric acid concentration in urine. The current mainstream method for detecting uric acid requires an enzyme (urate oxidase), which needs to be stored in a low-temperature environment, and the method requires complex chemical steps, which takes a longer time and more samples. In this study, we propose an integrated miniature three-electrode electrochemical surface-enhanced Raman spectroscopy chip (EC-SERS chip) suitable for rapid EC-SERS detection applications. The integrated microfluidic reservoir on the chip makes it easy to use, which is very suitable for rapid detection applications. The SERS active working electrode for the proposed integrated EC-SERS chip is a nanocone array polycarbonate (PC) substrate decorated with an evenly distributed and tightly packed array of gold nanospheres. It showed good uniformity and can be easily reproduced. The integrated EC-SERS chip is very small compared to the traditional electrochemical cell, which reduces the sample volume required for the testing. In addition, the chip is for one-time use only. It eliminates the need to clean electrochemical cells for reuse, thereby reducing the possibility of contamination and inaccurate detection. Various low-concentration Rhodamine 6G (R6G) solutions were tested to verify the performance of the developed EC-SERS chip. Experimental results showed that the proposed EC-SERS chip has a strong enhancement factor of up to 8.5 × 106 and a very good EC-SERS uniformity (the relative standard deviation of EC-SERS intensity is as low as 1.41%). The EC-SERS chip developed has been further tested for the detection of uric acid in synthetic urine. The results showed that the EC-SERS signal intensity has a highly linear relationship with the logarithm of the uric acid concentration in synthetic urine, which indicates that the developed EC-SERS chip is suitable for the quantitative detection of uric acid in synthetic urine. Therefore, the developed EC-SERS chip is very promising to be used in routine and early diagnosis of pregnancy toxemia and may be used in many other medical tests, food safety, and biotechnology applications.

show abstract

The Metallurgy of Anodizing Aluminum

Cited by 61 publications

References 0 publications

Tunable Silver Nanoparticle Arrays by Hot Embossing and Sputter Deposition for Surface-Enhanced Raman Scattering

Tunable Silver Nanoparticle Arrays by Hot Embossing and Sputter Deposition for Surface-Enhanced Raman Scattering

The Sealing Step in Aluminum Anodizing: A Focus on Sustainable Strategies for Enhancing Both Energy Efficiency and Corrosion Resistance

Integrated EC-SERS Chip with Uniform Nanostructured EC-SERS Active Working Electrode for Rapid Detection of Uric Acid

Contact Info

Product

Resources

About