Aluminum oxide membrane

Figure 2.14. The structure of an anodized aluminum oxide membrane (Anopore) as shown in Anotec Separations (1986) (a) is a homogeneous membrane (b) an asymmetric membrane.

Figure 2.16. Production scheme of a anodic aluminum oxide membrane (Smith 1973,1974).

Mitrovic, M. and L. Knezic. 1979. Electrolytic aluminum oxide membranes -a new kind of membrane with reverse osmosis characteristics. Desalination 28 147-56. 

Smith, A. W. 1973. Porous anodic aluminum oxide membrane. J. Electrochem. Soc. 120(8) 1068-69. 

Konno, M., M. Shindo, S. Sugawara and S. Saito. 1988. A composite palladium and porous aluminum oxide membrane for hydrogen gas separation, J. Membr, Sci. 37 193-97. 

Fumeaux, R. C., A. P. Davidson and M. D. Ball. 1987. Porous anodic aluminum oxide membrane catalyst support. European Patent Appl. 0,244,970A1. 

Skerlos, S.J., Rajagopalan, N., DeVor, R.E., Kapoor, S.G., and Angspatt, V.D., Microfiltration polyoxyalkylene metalworking fluid lubricant additives using aluminum oxide membranes, J. Man. Sci. Eng. Trans., 123, 692-699, 2001. 

Xiong G, Elam JW, Feng H, Han CY, Wang HH, Iton LE, Curtiss LA, Pellin MJ, Rung M, Kung H, Starr PC (2005) Effect of atomic layer deposition coatings on the surface structure of anodic aluminum oxide membranes. J Phys Chem B 109 14059... 

Evans PR, Yi G, Schwarzacher W (2000) Current perpendicular to plane giant magnetoresistance of multilayered nanowires electrodeposited in anodic aluminum oxide membranes. Appl Phys Lett 76 481 83... 

Figure 7.3 AFM images of anodic aluminum oxide membrane (a), and Zn-Ni alloy nanorods (b, c) obtained using double templates (liquid crystal and AAO). (b) and (c) were obtained with different deposition charges, 0.6 C and 0.9 C, respectively. The scale of each picture is 1.6 x 1.6 p,m. (Reprinted from A. Foyet et al. J. Electroanal. Chem. 2007, 604, 137. Copyright (2007) Elsevier. With permission.)...

Gold nanowire arrays were also used by Andreu and coworkers for DNA detection [45]. Anodic aluminum oxide membranes were used as templates for galvanostatic Au electrodeposition followed by treatment in base to dissolve away the template leaving freestanding gold nanowires 330 nm in diameter and 2 fim in length. [Ru(NH3)6] + was used to measure charge before and after... 

For template-based parylene, anodized aluminum oxide membranes with 100 nm of pore diameters and a thickness of 60 xm are placed into a deposition chamber. Using surface characterization techniques, both approaches have been compared. 

One of the features of inorganic membranes is their controlled pore structure. Anodic aluminum oxide membranes have uniform cylindrical pores, and were applied to an investigation of the analysis of transport mechanism [ 12]. Another route involves the application of a micelle template to membrane preparation [44]. Cubic mesoporous silica (MCM48) membranes were prepared on a stainless steel supports [45] to possible applications for filtration membranes and membrane reactions. 

A novel one-sided NMR magnet has been developed for self-diffusion measurements in thin samples [7]. Using this technique, researchers have demonstrated measurements in bulk [BMIM][TFSI] and [BMIM][TFSI] confined in nanoporous anodized aluminum oxide membranes, as shown in Fig. 3. This operates at a proton Larmor frequency of 14.08 MFlz, and the expected appHcation is toward in situ measurements in portable energy devices. This method utilizes the fringe field to measure diffusion coefficients instead of conventional PFG-NMR. 

According to Homyak et al. (17), the electropolished aluminum is rinsed immediately in distilled water (often with the aid of a strong stream of distilled water to remove the tenacious gelatinous oxide layer), immersed in concentrated nitric acid for 10 min, rinsed and left to dry in air. Well-polished aluminum should present a shiny/mirror-like surface accurate polishing is crucial for obtaining high-quality aluminum oxide membranes. 

Figure 1.2 Scanning electron microscope image of a piece of a porous aluminum oxide membrane lying on top of a continuous membrane. (Courtesy of H. Duran.)...

Investigations have been conducted with polycarbonate track-etched templates, aluminum oxide membranes and nonporous mica [344-352], and in all cases the nanomaterial preparation consists primarily of a controlled electrodeposition of copper from a precursor solution (usually CUSO4) inside the nanochannels of the template. In a second step, the template is removed, thus releasing the elongated nanostructures. By following this approach, Gao and coworkers [353] prepared dense and continuous copper nanowires which were 30 xm long and had a uniform... 

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