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Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 48, Iss. 8 — Mar. 10, 2009
  • pp: 1514–1519

Modeling the absorption behavior of solar thermal collector coatings utilizing graded a - C : H / Ti C layers

D. P. Gruber, G. Engel, H. Sormann, A. Schüler, and W. Papousek  »View Author Affiliations

Applied Optics, Vol. 48, Issue 8, pp. 1514-1519 (2009)

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Wavelength selective coatings are of common use in order to enhance the efficiency of devices heated by radiation such as solar thermal collectors. The use of suitable materials and the optimization of coating layer thicknesses are advisable ways to maximize the absorption. Further improvement is achievable by embedding particles in certain layers in order to modify material properties. We focus on optimizing the absorption behavior of a solar collector setup using copper as substrate, a layer of amorphous hydrogenated carbon with embedded titanium carbide particles ( a - C : H / Ti C ), and an antireflection coating of amorphous silicon dioxide ( a SiO 2 ). For the setup utilizing homogeneous particle distribution, a relative absorption of 90.98% was found, while inhomogeneous particle embedding yielded 98.29%. These results are particularly interesting since until now, absorption of more than 95% was found only by using embedded Cr but not by using the more biocompatible Ti.

© 2009 Optical Society of America

OCIS Codes
(240.0310) Optics at surfaces : Thin films
(160.2710) Materials : Inhomogeneous optical media

ToC Category:
Optics at Surfaces

Original Manuscript: November 19, 2008
Revised Manuscript: February 4, 2009
Manuscript Accepted: February 9, 2009
Published: March 4, 2009

D. P. Gruber, G. Engel, H. Sormann, A. Schüler, and W. Papousek, "Modeling the absorption behavior of solar thermal collector coatings utilizing graded α-C:H/TiC layers," Appl. Opt. 48, 1514-1519 (2009)

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