Structure of low-density nanoporous dielectrics revealed by low-vacuum electron microscopy and small-angle X-ray scattering

Aerogels (AGs) are ultralow-density nanoporous solids that have numerous potential applications. However, as most AGs are strong insulators with poor mechanical properties, direct studies of the complex nanoporous structure of AGs by methods such as atomic force and conventional scanning electron mi...

Description complète

Détails bibliographiques
Publié dans:Langmuir : the ACS journal of surfaces and colloids. - 1985. - 23(2007), 2 vom: 16. Jan., Seite 353-6
Auteur principal: Kucheyev, Sergei O (Auteur)
Autres auteurs: Toth, Milos, Baumann, Theodore F, Hamza, Alex V, Ilavsky, Jan, Knowles, W Ralph, Saw, Cheng K, Thiel, Bradley L, Tileli, Vasiliki, Buuren, Tony van, Wang, Y Morris, Willey, Trevor M
Format: Article
Langue:English
Publié: 2007
Accès à la collection:Langmuir : the ACS journal of surfaces and colloids
Sujets:Journal Article
Description
Résumé:Aerogels (AGs) are ultralow-density nanoporous solids that have numerous potential applications. However, as most AGs are strong insulators with poor mechanical properties, direct studies of the complex nanoporous structure of AGs by methods such as atomic force and conventional scanning electron microscopy (SEM) have not proven feasible. Here, we use low-vacuum SEM to image directly the ligament and pore size and shape distributions of representative AGs over a wide range of length scales (approximately 100-105 nm). The structural information obtained is used for unambiguous, real-space interpretation of small-angle X-ray scattering curves for these complex nanoporous systems. Low-vacuum SEM permits imaging of both cross-sections and skin layers of AG monoliths. Images of skin layers reveal the presence of microcracks, which alter the properties of cast monolithic AGs
Description:Date Completed 17.07.2007
Date Revised 09.01.2007
published: Print
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827