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The Journal of Physical Chemistry C, 2014
ABSTRACT We present a systematic study of membrane structure (pore diameter and arrangement) in a... more ABSTRACT We present a systematic study of membrane structure (pore diameter and arrangement) in anodized aluminum oxide (AAO) layers obtained by anodization voltages 8–20 V in sulfuric and 15–40 V in oxalic acid electrolyte solutions. Anodization of bulk aluminum in sulfuric acid at 10 V potential was found to be optimal for production or ultrathin freestanding membranes with pore diameter in sub-20 nm range. The developed process with slow electrochemical reaction results in AAO membranes with thickness below 70 nm. The minimum required time for formation of continuous AAO membrane was determined and influence of electrolyte concentration on pore diameter in membrane after barrier layer removal analyzed. Finally, we demonstrate a method of membrane transfer onto a different surface and using it for masked deposition of dense nanoparticle arrays with diameters below 20 nm.
IOP Conference Series: Materials Science and Engineering, 2011
Formation of ultrathin anodised aluminium oxide (AAO) membranes with high aspect ratio by Al anod... more Formation of ultrathin anodised aluminium oxide (AAO) membranes with high aspect ratio by Al anodization in sulphuric and oxalic acids at low potentials was investigated. Low anodization potentials ensure slow electrochemical reaction speeds and formation of AAO membranes with pore diameter and thickness below 20 nm and 70 nm respectively. Minimum time necessary for formation of continuous AAO membranes was determined. AAO membrane pore surface was covered with polymer Paraloid B72 TM to transport it to the selected substrate. The fabricated ultra thin AAO membranes could be used to fabricate nanodot arrays on different surfaces.
Plasmonics, 2013
ABSTRACT We address the optical properties of dense disordered yet well-separated metal nanoparti... more ABSTRACT We address the optical properties of dense disordered yet well-separated metal nanoparticle arrays produced by physical vapor deposition through anodized aluminum oxide membrane masks. Using variations in synthesis parameters, the particle diameters vary from 14 to 50 nm and average center separation from 45 to 112 nm. Ag nanoparticle arrays with no long-range periodicity exhibit apparently random formation of high-intensity depolarized regions relative to orientation of incident electric field. We analyze this behavior numerically using coupled dipole model and explain the contrast formation in recorded scattering images.
The Journal of Physical Chemistry C, 2014
ABSTRACT We present a systematic study of membrane structure (pore diameter and arrangement) in a... more ABSTRACT We present a systematic study of membrane structure (pore diameter and arrangement) in anodized aluminum oxide (AAO) layers obtained by anodization voltages 8–20 V in sulfuric and 15–40 V in oxalic acid electrolyte solutions. Anodization of bulk aluminum in sulfuric acid at 10 V potential was found to be optimal for production or ultrathin freestanding membranes with pore diameter in sub-20 nm range. The developed process with slow electrochemical reaction results in AAO membranes with thickness below 70 nm. The minimum required time for formation of continuous AAO membrane was determined and influence of electrolyte concentration on pore diameter in membrane after barrier layer removal analyzed. Finally, we demonstrate a method of membrane transfer onto a different surface and using it for masked deposition of dense nanoparticle arrays with diameters below 20 nm.
IOP Conference Series: Materials Science and Engineering, 2011
Formation of ultrathin anodised aluminium oxide (AAO) membranes with high aspect ratio by Al anod... more Formation of ultrathin anodised aluminium oxide (AAO) membranes with high aspect ratio by Al anodization in sulphuric and oxalic acids at low potentials was investigated. Low anodization potentials ensure slow electrochemical reaction speeds and formation of AAO membranes with pore diameter and thickness below 20 nm and 70 nm respectively. Minimum time necessary for formation of continuous AAO membranes was determined. AAO membrane pore surface was covered with polymer Paraloid B72 TM to transport it to the selected substrate. The fabricated ultra thin AAO membranes could be used to fabricate nanodot arrays on different surfaces.
Plasmonics, 2013
ABSTRACT We address the optical properties of dense disordered yet well-separated metal nanoparti... more ABSTRACT We address the optical properties of dense disordered yet well-separated metal nanoparticle arrays produced by physical vapor deposition through anodized aluminum oxide membrane masks. Using variations in synthesis parameters, the particle diameters vary from 14 to 50 nm and average center separation from 45 to 112 nm. Ag nanoparticle arrays with no long-range periodicity exhibit apparently random formation of high-intensity depolarized regions relative to orientation of incident electric field. We analyze this behavior numerically using coupled dipole model and explain the contrast formation in recorded scattering images.