Silica Sol-gel Coatings with Improved Light Transmittance and Stability

  • Lenke Kócs Budapest University of Technology and Economics, Department of Physical Chemistry and Materials Science, Centre for Colloid Chemistry H-1521 Budapest, Budafoki út 6-8, Hungary
  • Emőke Albert Budapest University of Technology and Economics, Department of Physical Chemistry and Materials Science, Centre for Colloid Chemistry H-1521 Budapest, Budafoki út 6-8, Hungary
  • Borbála Tegze Budapest University of Technology and Economics, Department of Physical Chemistry and Materials Science, Centre for Colloid Chemistry H-1521 Budapest, Budafoki út 6-8, Hungary
  • Márta Kabai-Faix Budapest University of Technology and Economics, Department of Physical Chemistry and Materials Science, Centre for Colloid Chemistry H-1521 Budapest, Budafoki út 6-8, Hungary
  • Csaba Major Hungaro Lux Light Ltd., H-1171 Budapest, Strázsahegyi dűlő 7, Hungary
  • András Szalai Hungaro Lux Light Ltd., H-1171 Budapest, Strázsahegyi dűlő 7, Hungary
  • Péter Basa Semilab Semiconductor Physics Laboratory Co. Ltd. H-1117 Budapest, Prielle Kornélia str. 2, Hungary
  • Zoltán Hórvölgyi Budapest University of Technology and Economics, Department of Physical Chemistry and Materials Science, Centre for Colloid Chemistry H-1521 Budapest, Budafoki út 6-8, Hungary

Abstract

Silica sol-gel coatings on different substrate materials and their use as model systems have been studied. Mesoporous silica coatings with thicknesses of 85 - 135 nm and porosity of 18 ˗ 37% were prepared by dip-coating on polycarbonate and glass substrates. In order to eliminate the shrinkage of the porous structure acid or base vapour treatment was applied. Thickness and refractive index of the coatings were determined by analysing the transmittance spectra of the samples. Ellipsometric porosimetry measurements were carried out to determine the porosity, pore radius distribution, thickness and refractive index. The thickness of the samples was further confirmed by scanning electron microscopy. The adsorption capacity of the porous coatings was also studied by dye impregnation tests. The temporal stability of the samples was investigated by UV-Vis spectrometry and it was found that the advantageous optical properties (Tmax = 98 – 99%) of the samples remained constant even after a 1 year storage period.

Keywords

sol-gel coating, improved light transmittance, long-term optical stability, network strengthening, porosity
Published in Onlinefirst
24-07-2017
How to Cite
KÓCS, Lenke et al. Silica Sol-gel Coatings with Improved Light Transmittance and Stability. Periodica Polytechnica Chemical Engineering, [S.l.], 2017. ISSN 1587-3765. Available at: <https://pp.bme.hu/ch/article/view/10550>. Date accessed: 23 nov. 2017. doi: https://doi.org/10.3311/PPch.10550.
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Articles