To main content

Nano Insulation Materials Exploiting the Knudsen Effect

Abstract

As the world's focus is turned even stronger toward miscellaneous energy efficiency and saving aspects, the development of new high-performance thermal insulation materials for building applications will play an important role in this regard. The aim of the presented study is to develop an understanding for the governing thermal transport mechanisms and utilize the Knudsen effect in nanoporous insulation materials through theoretical concepts and experimental laboratory explorations, thus being able to synthesize nano insulation materials (NIM) with very low thermal conductivity values as a major goal. NIMs based on hollow silica nanospheres (HSNS) have been synthesized by a sacrificial template method, where the idea is that the heat transport by gas conductance and gas/solid state interactions decreases with decreasing pore diameters in the nano range as predicted by the Knudsen effect. HSNS with reduced thermal conductivity compared to their solid counterparts have been prepared where the hollow sphere cavities and voids between the spheres are filled with air at atmospheric pressure, i.e. eliminating the need for various measures like e.g. protective metallized foils to maintain a vacuum or expensive low-conducting gases in the cavities and voids. Hence, HSNS represent a promising stepping-stone toward the future high-performance thermal insulation materials.
Read the publication

Category

Academic article

Language

English

Author(s)

Affiliation

  • SINTEF Community / Architecture, Materials and Structures
  • SINTEF Industry / Sustainable Energy Technology
  • SINTEF Industry / Materials and Nanotechnology
  • Norwegian University of Science and Technology

Year

2019

Published in

IOP Conference Series: Materials Science and Engineering

ISSN

1757-8981

Volume

634

Page(s)

1 - 7

View this publication at Norwegian Research Information Repository