A New Technique for Batch Production of Tubular Anodic Aluminum Oxide Films for Filtering Applications

Abstract

Abstract:With larger surface areas and nanochannels for mass delivery and gas diffusion, three-dimensional tubular anodic aluminum oxide (AAO) films have practical advantages over two-dimensional AAO films for medical and energy applications. In this research, we have developed a process for batch production of tubular AAO films using a 6061 Al tube. The tubular AAO films have open nano-channels on both sides, with average pore dimensions of about 60 nm and pore densities of about 10 8 to 10 9 pore/cm 2 . It was found that the porous AAO material with nano-channel structure exhibited dialysis behavior, allowing for liquid/gas exudation through diffusion between the inner and outer surfaces of the tubular AAO films. Ar gas bearing test and aeration test were conducted to find the pressure bearing capacity of tubular AAO films. It was demonstrated that the AAO film with a thickness of 100 µm can resist an argon pressure up to 8 atm; however, 30 µm AAO film can only withstand 3 atm of Ar gas. The tubular AAO films with exudation characteristics have the potential for applications in advanced technologies, such as liquid or gas filters, drug delivery, and energy applications.

Electrodeposition of One-Dimensional Nanostructures: Environmentally Friendly Method

“…Porous AAO film grown on aluminum is composed of a thin barrier oxide layer in conformal contact with aluminum, and an overlying, relatively thick, porous oxide film containing mutually parallel nanopores extends from the barrier oxide layer to the film surface [7]. Each cylindrical nanopore and its surrounding oxide region constitute a hexagonal cell aligned normal to the metal surface.…”

“…Each cylindrical nanopore and its surrounding oxide region constitute a hexagonal cell aligned normal to the metal surface. Under specific electrochemical conditions, the oxide cells self-organize into hexagonal close-packed arrangement, forming a honeycomb-like structure [5][6][7]. Pore diameter and density of selfordered porous AAOs are tunable in wide ranges by .…”

“…One is the template-assisted electrodeposition, where the 1D anisotropic growth is performed by using various templates to confine the growth space of the electrodeposits. The templateassisted electrodeposition has been demonstrated to be a versatile approach for the preparation of the 1D nanostructures of numerous materials, including metals [7], semiconductors [8] and conductive polymers [9]. Another strategy is the template-free electrodeposition, where the 1D anisotropic growth is achieved by utilizing the intrinsic anisotropic crystallographic structure of a targeted material.…”

Special Issue on “Mechanical Behaviour of Aluminium Alloys”

“…The introduction and certification of such products is a strategic aspect in this ambit. This can be exemplified by a work by Hun et al [11] who develop a new technique for the mass production of tubular anodic aluminium oxide films from 6061 aluminium alloy tubes, which can be applied in filtering, dialysis, and gas-diffuser processes.…”

A Modified Interposer Fabrication Process by Copper Nano-Pillars Filled in Anodic Aluminum Oxide Film for 3D Electronic Package

“…Unfortunately, the formation of the vias in glass with a diameter of less than 50 µm was proved to be very difficult due to the frangibility of glass. Anodic aluminum oxide (AAO) films can provide natural close-packed parallel cylindrical nano-pores [9][10][11], thus the drilling process and other high-cost processes for via pores can be avoided.…”