Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying

Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying

Attenuated Total Reflectance Infrared (ATR-IR) spectroscopy and texture measurements based on nitrogen adsorption-desorption isotherms are combined to characterize silica aerogel granules with different degrees of hydrophobicity. The aerogels were prepared from tetraethoxysilane via a room temperatu...

Full description

Bibliographic Details
Main Authors: Dimitar Shandurkov, Petar Ignatov, Ivanka Spassova, Stoyan Gutzov
Format: Article
Language:English
Published: MDPI AG 2021-03-01
Series:Molecules
Subjects:
sol-gel
aerogel
IR
adsorption
fractal dimension
Online Access:https://www.mdpi.com/1420-3049/26/6/1796
id doaj-7d18ff73452949359cad9f60ba3199eb
record_format Article
spelling doaj-7d18ff73452949359cad9f60ba3199eb2021-03-24T00:01:03ZengMDPI AGMolecules1420-30492021-03-01261796179610.3390/molecules26061796Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature DryingDimitar Shandurkov0Petar Ignatov1Ivanka Spassova2Stoyan Gutzov3Faculty of Chemistry and Pharmacy, Department of Physical Chemistry, University of Sofia St. Kliment Ohridski, 1164 Sofia, BulgariaFaculty of Chemistry and Pharmacy, Department of Physical Chemistry, University of Sofia St. Kliment Ohridski, 1164 Sofia, BulgariaBulgarian Academy of Sciences, Institute of General and Inorganic Chemistry, 1113 Sofia, BulgariaFaculty of Chemistry and Pharmacy, Department of Physical Chemistry, University of Sofia St. Kliment Ohridski, 1164 Sofia, BulgariaAttenuated Total Reflectance Infrared (ATR-IR) spectroscopy and texture measurements based on nitrogen adsorption-desorption isotherms are combined to characterize silica aerogel granules with different degrees of hydrophobicity. The aerogels were prepared from tetraethoxysilane via a room temperature hydrolysis-gelation process, solvent exchange, hydrophobization, and drying at subcritical conditions. The dependencies between the texture properties, pore architectures, surface fractal dimensions, and degree of hydrophobicity of the samples are extracted from the ATR-IR spectra and the adsorption-desorption isotherms. The IR absorption in the region of the Si-O-Si and Si-OH vibrations is used for a description of the structural and chemical changes in aerogel powders connected with their surface hydrophobization. The Frenkel–Halsey–Hill (FHH) theory is applied to determine the surface fractal dimension of the powder species.https://www.mdpi.com/1420-3049/26/6/1796sol-gelaerogelIRadsorptionfractal dimension
collection DOAJ
language English
format Article
sources DOAJ
author Dimitar Shandurkov
Petar Ignatov
Ivanka Spassova
Stoyan Gutzov
spellingShingle Dimitar Shandurkov
Petar Ignatov
Ivanka Spassova
Stoyan Gutzov
Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying
Molecules
sol-gel
aerogel
IR
adsorption
fractal dimension
author_facet Dimitar Shandurkov
Petar Ignatov
Ivanka Spassova
Stoyan Gutzov
author_sort Dimitar Shandurkov
title Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying
title_short Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying
title_full Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying
title_fullStr Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying
title_full_unstemmed Spectral and Texture Properties of Hydrophobic Aerogel Powders Obtained from Room Temperature Drying
title_sort spectral and texture properties of hydrophobic aerogel powders obtained from room temperature drying
publisher MDPI AG
series Molecules
issn 1420-3049
publishDate 2021-03-01
description Attenuated Total Reflectance Infrared (ATR-IR) spectroscopy and texture measurements based on nitrogen adsorption-desorption isotherms are combined to characterize silica aerogel granules with different degrees of hydrophobicity. The aerogels were prepared from tetraethoxysilane via a room temperature hydrolysis-gelation process, solvent exchange, hydrophobization, and drying at subcritical conditions. The dependencies between the texture properties, pore architectures, surface fractal dimensions, and degree of hydrophobicity of the samples are extracted from the ATR-IR spectra and the adsorption-desorption isotherms. The IR absorption in the region of the Si-O-Si and Si-OH vibrations is used for a description of the structural and chemical changes in aerogel powders connected with their surface hydrophobization. The Frenkel–Halsey–Hill (FHH) theory is applied to determine the surface fractal dimension of the powder species.
topic sol-gel
aerogel
IR
adsorption
fractal dimension
url https://www.mdpi.com/1420-3049/26/6/1796
work_keys_str_mv AT dimitarshandurkov spectralandtexturepropertiesofhydrophobicaerogelpowdersobtainedfromroomtemperaturedrying
AT petarignatov spectralandtexturepropertiesofhydrophobicaerogelpowdersobtainedfromroomtemperaturedrying
AT ivankaspassova spectralandtexturepropertiesofhydrophobicaerogelpowdersobtainedfromroomtemperaturedrying
AT stoyangutzov spectralandtexturepropertiesofhydrophobicaerogelpowdersobtainedfromroomtemperaturedrying
_version_ 1724205497453641728

Similar Items