Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces

Ekin Su Eskiizmirliler; Erkan Ersöz; Nilay Gizli

doi:10.35860/iarej.1826118

Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces

Abstract

Silica aerogels possess unique properties, such as high surface area, high porosity, low density, low thermal conductivity, and low refractive index. Their nanoscale porous structure and three-dimensional network make them promising materials for thermal insulation by effectively suppressing heat transfer via solid conduction and stagnant gas conduction. However, the presence of surface silanol groups renders conventional silica aerogels inherently hydrophilic and limits their practical applicability. In this study, transparent, thermally insulating, hydrophobic, and self-cleaning multifunctional silica-based aerogel nanocoatings were developed for glass substrates to reduce heat loss. The films were synthesized by the sol-gel method by using tetraethyl orthosilicate (TEOS) as the main silica precursor, and glycidoxypropyltrimethoxysilane (GLYMO) and aminopropyltriethoxysilane (APTES) were employed as epoxy- and amine-functional co-precursors, respectively. To further enhance the hydrophobicity, the coated surfaces were modified with trimethylchlorosilane (TMCS). The effects of surface modification and coating methods (dip and spin coating) on the optical, hydrophobic, and thermal properties were systematically investigated. The results showed that the samples produced using the spin-coated method exhibited the highest optical transparency, reaching up to 98.4%. Surface modification increased the water contact angle from 40° (bare glass) to 108°. Moreover, the fact that all surfaces exhibited contact angle hysteresis below 15° indicated effective self-cleaning capabilities. Thermal insulation performance of the coatings was evaluated comparatively using an insulated closed-box system under a constant heat source by monitoring the temperature difference between the upper and lower surfaces. Compared with all other samples, the unmodified spin-coated sample exhibited the highest temperature difference (ΔTmax = 5.38 °C) but the lowest thermal conductivity (k = 0.1231 W m⁻¹ K⁻¹). This study demonstrates that high optical transparency, effective thermal insulation, and hydrophobicity can be integrated within a single silica aerogel-based coating system. These multifunctional properties can be customized through controlled surface chemistry and coating parameters, presenting a practical and scalable strategy for energy-efficient glass applications.

Keywords

Supporting Institution

This study is supported by The Scientific and Technological Research Council of Turkey (TUBİTAK), under contract No: 5230125 TEYDEB 1505.

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Details

Primary Language

English

Subjects

Materials Science and Technologies

Journal Section

Research Article

Authors

Ekin Su Eskiizmirliler
0009-0000-6956-8145
Türkiye

Erkan Ersöz
0000-0001-6880-9891
Türkiye

Nilay Gizli ^*
0000-0002-7591-1365
Türkiye

Publication Date

August 25, 2026

Submission Date

January 15, 2026

Acceptance Date

June 18, 2026

Published in Issue

Year 2026 Volume: 10 Number: 2

DOI

https://doi.org/10.35860/iarej.1826118

IZ

https://izlik.org/JA22ZK63LP

Cite

RIS / Bibtex

APA

Eskiizmirliler, E. S., Ersöz, E., & Gizli, N. (2026). Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces. International Advanced Researches and Engineering Journal, 10(2), 98-106. https://doi.org/10.35860/iarej.1826118

AMA

1.Eskiizmirliler ES, Ersöz E, Gizli N. Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces. Int. Adv. Res. Eng. J. 2026;10(2):98-106. doi:10.35860/iarej.1826118

Chicago

Eskiizmirliler, Ekin Su, Erkan Ersöz, and Nilay Gizli. 2026. “Multifunctional Silica Aerogel Nanocoatings for Enhanced Thermal Insulation of Glass Surfaces”. International Advanced Researches and Engineering Journal 10 (2): 98-106. https://doi.org/10.35860/iarej.1826118.

EndNote

Eskiizmirliler ES, Ersöz E, Gizli N (August 1, 2026) Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces. International Advanced Researches and Engineering Journal 10 2 98–106.

IEEE

[1]E. S. Eskiizmirliler, E. Ersöz, and N. Gizli, “Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces”, Int. Adv. Res. Eng. J., vol. 10, no. 2, pp. 98–106, Aug. 2026, doi: 10.35860/iarej.1826118.

ISNAD

Eskiizmirliler, Ekin Su - Ersöz, Erkan - Gizli, Nilay. “Multifunctional Silica Aerogel Nanocoatings for Enhanced Thermal Insulation of Glass Surfaces”. International Advanced Researches and Engineering Journal 10/2 (August 1, 2026): 98-106. https://doi.org/10.35860/iarej.1826118.

JAMA

1.Eskiizmirliler ES, Ersöz E, Gizli N. Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces. Int. Adv. Res. Eng. J. 2026;10:98–106.

MLA

Eskiizmirliler, Ekin Su, et al. “Multifunctional Silica Aerogel Nanocoatings for Enhanced Thermal Insulation of Glass Surfaces”. International Advanced Researches and Engineering Journal, vol. 10, no. 2, Aug. 2026, pp. 98-106, doi:10.35860/iarej.1826118.

Vancouver

1.Ekin Su Eskiizmirliler, Erkan Ersöz, Nilay Gizli. Multifunctional silica aerogel nanocoatings for enhanced thermal insulation of glass surfaces. Int. Adv. Res. Eng. J. 2026 Aug. 1;10(2):98-106. doi:10.35860/iarej.1826118