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Title: W:Al 2O 3 nanocomposite thin films with tunable optical properties prepared by atomic layer deposition

Abstract

Here, a systematic alteration in the optical properties of W:Al 2O 3 nanocomposite films is demonstrated by precisely varying the W cycle percentage (W%) from 0 to 100% in Al 2O 3 during atomic layer deposition. The direct and indirect band energies of the nanocomposite materials decrease from 5.2 to 4.2 eV and from 3.3 to 1.8 eV, respectively, by increasing the W% from 10 to 40. X-ray absorption spectroscopy reveals that, for W% < 50, W is present in both metallic and suboxide states, whereas, for W% ≥ 50, only metallic W is seen. This transition from dielectric to metallic character at W% ~ 50 is accompanied by an increase in the electrical and thermal conductivity and the disappearance of a clear band gap in the absorption spectrum. The density of the films increases monotonically from 3.1 g/cm 3 for pure Al 2O 3 to 17.1 g/cm 3 for pure W, whereas the surface roughness is greatest for the W% = 50 films. The W:Al 2O 3 nanocomposite films are thermally stable and show little change in optical properties upon annealing in air at 500 °C. These W:Al 2O 3 nanocomposite films show promise as selective solar absorption coatingsmore » for concentrated solar power applications.« less

Authors:
 [1];  [1];  [1];  [2];  [2];  [1]
  1. Argonne National Lab. (ANL), Argonne, IL (United States)
  2. Univ. of Illinois at Urbana-Champaign, Champaign, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1332989
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. C
Additional Journal Information:
Journal Volume: 120; Journal Issue: 27; Journal ID: ISSN 1932-7447
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Babar, Shaista, Mane, Anil U., Yanguas-Gil, Angel, Mohimi, Elham, Haasch, Richard T., and Elam, Jeffrey W. W:Al2O3 nanocomposite thin films with tunable optical properties prepared by atomic layer deposition. United States: N. p., 2016. Web. doi:10.1021/acs.jpcc.6b03823.
Babar, Shaista, Mane, Anil U., Yanguas-Gil, Angel, Mohimi, Elham, Haasch, Richard T., & Elam, Jeffrey W. W:Al2O3 nanocomposite thin films with tunable optical properties prepared by atomic layer deposition. United States. doi:10.1021/acs.jpcc.6b03823.
Babar, Shaista, Mane, Anil U., Yanguas-Gil, Angel, Mohimi, Elham, Haasch, Richard T., and Elam, Jeffrey W. 2016. "W:Al2O3 nanocomposite thin films with tunable optical properties prepared by atomic layer deposition". United States. doi:10.1021/acs.jpcc.6b03823. https://www.osti.gov/servlets/purl/1332989.
@article{osti_1332989,
title = {W:Al2O3 nanocomposite thin films with tunable optical properties prepared by atomic layer deposition},
author = {Babar, Shaista and Mane, Anil U. and Yanguas-Gil, Angel and Mohimi, Elham and Haasch, Richard T. and Elam, Jeffrey W.},
abstractNote = {Here, a systematic alteration in the optical properties of W:Al2O3 nanocomposite films is demonstrated by precisely varying the W cycle percentage (W%) from 0 to 100% in Al2O3 during atomic layer deposition. The direct and indirect band energies of the nanocomposite materials decrease from 5.2 to 4.2 eV and from 3.3 to 1.8 eV, respectively, by increasing the W% from 10 to 40. X-ray absorption spectroscopy reveals that, for W% < 50, W is present in both metallic and suboxide states, whereas, for W% ≥ 50, only metallic W is seen. This transition from dielectric to metallic character at W% ~ 50 is accompanied by an increase in the electrical and thermal conductivity and the disappearance of a clear band gap in the absorption spectrum. The density of the films increases monotonically from 3.1 g/cm3 for pure Al2O3 to 17.1 g/cm3 for pure W, whereas the surface roughness is greatest for the W% = 50 films. The W:Al2O3 nanocomposite films are thermally stable and show little change in optical properties upon annealing in air at 500 °C. These W:Al2O3 nanocomposite films show promise as selective solar absorption coatings for concentrated solar power applications.},
doi = {10.1021/acs.jpcc.6b03823},
journal = {Journal of Physical Chemistry. C},
number = 27,
volume = 120,
place = {United States},
year = 2016,
month = 6
}

Journal Article:
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  • Cited by 3
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