Dust Repellent Materials

Bekir S. Yilbas*, Ghassan Hassan, Abdullah Al-Sharafi

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingChapterpeer-review

Abstract

Selective surfaces, such as zirconium nitride, tungsten oxide, etc., are used in solar volumetric receivers and these surfaces can harvest solar energy for concentrated solar heating applications. In addition, optical properties, such as low absorption and high transmittance, of protective covers for photovoltaic panels are critical for efficient energy harvesting process. Environmental dusts have detrimental effect on the device performance due to degrading of the optical transmittance of such covers. The dust settlements on selective surfaces have similar effects on the solar receiver performances because of diffusion and scattering of incident solar energy by the dust particles on the surface. Depending on the size and dust particles distribution, the light scattering and optical diffusion causes total blockage of the incident solar radiation reaching at the active device surface. In addition, water condensates onto the dust particles in humid air ambient and cause dissolution of alkaline (Na, K) and alkaline earth metal (Ca) compounds. This, in turn, results in formation of chemically active fluid film while modifying the characteristics of the selective or transparent surfaces. Consequently, removal of dust particles becomes essential prior to formation of chemically active fluid. Several methods are possible to remove the dust particles from the surfaces, the main concern is to reduce the dust adhesion on the active surfaces. This can be achieved through generating micro/nano size air gaps between the dust particles and the selective surface. In addition, lowering surface energy of the selective surface is also favorable to reduce the dust adhesion on the surfaces. In the case of metals, such as zirconium, the nitride formation at the surface with micro/nanoscale surface texture lowers the surface energy and reduces the contact area between the dust particles and the surface. In order to form a zirconium nitride and micro/nano size pillars at the surface, a high intensity laser beam texturing under the high pressure nitrogen gas environment becomes necessary. Laser texturing also provides hydrophobic surface characteristics via forming micro/nano pillars at the surface; however, environmental dust settlement on textured surface influences the surface characteristics significantly. In the present chapter, fundamental understanding of dust particles characteristics such as size, shape, elemental composition, and adhesion on the selective surfaces are presented. Some sample examples such as laser texturing of ceramic (zirconia) and metallic (tungsten) surfaces are to be explored. The effects of the dust particles on the textured surface in a humid air ambient are to be investigated. Analytical tools used to assess the morphological changes on the laser textured surface prior and after the dust settlement in the humid air ambient are also presented.

Original languageEnglish
Title of host publicationEnergy Materials
PublisherElsevier Inc.
Pages832-880
Number of pages49
Volume2-5
ISBN (Electronic)9780128095973
ISBN (Print)9780128149256
DOIs
StatePublished - 7 Feb 2018

Bibliographical note

Publisher Copyright:
© 2018 Elsevier Inc. All rights reserved.

Keywords

  • Energy harvesting
  • Environmental dust
  • Hydrophobic
  • Repelling
  • Self-cleaning

ASJC Scopus subject areas

  • General Environmental Science

Fingerprint

Dive into the research topics of 'Dust Repellent Materials'. Together they form a unique fingerprint.

Cite this