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Title: AAO nanowells : synthesis, in-situ growth study, and applications in ultra-sensitive chemical detection.

Abstract

Anodized aluminum oxide (AAO) membranes consist of locally highly ordered nanopores. The pore diameter (20-200 nm) and pore-to-pore distance are controlled through the anodizing voltage and the choice of etching solution. High aspect ratio over 1,000 can easily be achieved which makes AAO membranes the ideal templates for making nanowires and nanotubes. In this work, the early stage of nanopore formation was studied in-situ with the use of small angle x-ray scattering (SAXS) and glazing incidence GISAXS techniques. The nanopores were found to grow as a function of the square root of growth time. The resulting short nanopores or nanowells with length below 200 nm were further characterized with use of SEM and AFM. These AAO nanowells showed interference color. Their reflectance UV-Vis spectra indicated strong angular dependence and can be understood with a simple single layer (nanoporous alumina over aluminum) model. These spectra are influenced by the nanowells thickness and diameter. Therefore, large array of interferometric AAO nanowells sensors are possible. When these nanowells are coated with Ag or Au thin films, in addition to enhanced interference color, highly sensitive surface enhanced Raman scattering (SERS) effect has been observed. These results will be presented.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
971465
Report Number(s):
ANL/MSD/CP-59235
TRN: US201004%%22
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Conference: 2006 Materials Research Society (MRS) Fall Meeting; Nov. 27, 2006 - Dec. 1, 2006; Boston, MA
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; ALUMINIUM OXIDES; QUANTUM WELLS; PORE STRUCTURE; SENSORS; DETECTION; MEMBRANES; SYNTHESIS; THIN FILMS

Citation Formats

Wang, H. H., Son, K.-I., Lee, B., Lu, J., and Han, C.. AAO nanowells : synthesis, in-situ growth study, and applications in ultra-sensitive chemical detection.. United States: N. p., 2007. Web.
Wang, H. H., Son, K.-I., Lee, B., Lu, J., & Han, C.. AAO nanowells : synthesis, in-situ growth study, and applications in ultra-sensitive chemical detection.. United States.
Wang, H. H., Son, K.-I., Lee, B., Lu, J., and Han, C.. Mon . "AAO nanowells : synthesis, in-situ growth study, and applications in ultra-sensitive chemical detection.". United States. doi:.
@article{osti_971465,
title = {AAO nanowells : synthesis, in-situ growth study, and applications in ultra-sensitive chemical detection.},
author = {Wang, H. H. and Son, K.-I. and Lee, B. and Lu, J. and Han, C.},
abstractNote = {Anodized aluminum oxide (AAO) membranes consist of locally highly ordered nanopores. The pore diameter (20-200 nm) and pore-to-pore distance are controlled through the anodizing voltage and the choice of etching solution. High aspect ratio over 1,000 can easily be achieved which makes AAO membranes the ideal templates for making nanowires and nanotubes. In this work, the early stage of nanopore formation was studied in-situ with the use of small angle x-ray scattering (SAXS) and glazing incidence GISAXS techniques. The nanopores were found to grow as a function of the square root of growth time. The resulting short nanopores or nanowells with length below 200 nm were further characterized with use of SEM and AFM. These AAO nanowells showed interference color. Their reflectance UV-Vis spectra indicated strong angular dependence and can be understood with a simple single layer (nanoporous alumina over aluminum) model. These spectra are influenced by the nanowells thickness and diameter. Therefore, large array of interferometric AAO nanowells sensors are possible. When these nanowells are coated with Ag or Au thin films, in addition to enhanced interference color, highly sensitive surface enhanced Raman scattering (SERS) effect has been observed. These results will be presented.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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