Microtribology of alumite disc using anodic oxidation

Aqueous Gold Sols of Rod-Shaped Particles

“…To release the rods, the aluminum oxide was dissolved in a 1.25 M NaOH solution. ,,,, Subsequently, the copper, which fixes the gold rods to the substrate, was selectively dissolved 26 resulting in rods lying flat on the substrate. Finally, 10 such samples were collected and dispersed into 2 mL of demineralized water by ultrasonification.…”

Colloidal Dispersions of Gold Rods: Synthesis and Optical Properties

“…Available templates are rod-shaped (inverted) micelles, [1][2][3][4] the so-called soft templates, or nanoporous membranes (hard templates). [6][7][8][9][10][11][12][13][14][15] The use of soft templates directly results in a dispersion of rod-shaped particles by UV irradiation. Hard templates require subsequent steps in which the solid template has to be replaced by a liquid in order to obtain a dispersion.…”

“…Furthermore, the pore diameter can be increased by slow dissolution of the hard template, enabling the preparation of rods with different sizes but the same aspect ratio. Extensive documentation is available for the electrodeposition of many metals in hard templates [6][7][8][9][10][11][12][13][14][15] because these (partially) filled membranes show, depending on the deposited material, interesting properties such as dichroism 7,13 or strong perpendicular magnetic anisotropy. [8][9][10] When rod-shaped particles are dispersed in a liquid instead of a solid, Brownian motion will occur, resulting in randomly oriented particles in the continuous phase.…”

“…Extensive documentation is available for the electrodeposition of many metals in hard templates [6][7][8][9][10][11][12][13][14][15] because these (partially) filled membranes show, depending on the deposited material, interesting properties such as dichroism 7,13 or strong perpendicular magnetic anisotropy. [8][9][10] When rod-shaped particles are dispersed in a liquid instead of a solid, Brownian motion will occur, resulting in randomly oriented particles in the continuous phase. This allows investigation of their dynamical behavior and their optical properties in a random orientation.…”

“…Therefore, in this study, we focus on the release of the rods from the membrane to an aqueous medium and on the stabilization of the dispersed particles before the optical properties are studied. A porous alumina template prepared by anodization of aluminum [7][8][9][10] was used as the template for the electrodeposition of gold. Under appropriate circumstances, this method enables the synthesis of dispersions of nearly monodisperse gold particles of adjustable aspect ratio.…”