Determination of the permeability of carbon aerogels by gas flow measurements
Abstract
Carbon aerogels are synthesized via the polycondensation of resorcinol and formaldehyde, followed by supercritical drying and pyrolysis at 1050{degree}C in nitrogen. Because of their interconnected porosity, ultrafine cell structure and high surface area, carbon aerogels have many potential applications, such as in supercapacitors, battery electrodes, catalyst supports, and gas filters. The performance of carbon aerogels in the latter two applications depends on the permeability or gas flow conductance in these materials. By measuring the pressure differential across a thin specimen and the nitrogen gas flow rate in the viscous regime, we calculated the permeability of carbon aerogels from equations based upon Darcy's law. Our measurements show that carbon aerogels have apparent permeabilities on the order of 10{sup {minus}12}to 10{sup {minus}10} cm{sup 2} for densities ranging from 0.44 to 0.05 g/cm{sup 3}. Like their mechanical properties, the permeability of carbon aerogels follows a power law relationship with density and average pore size. Such findings help us to estimate the average pore sizes of carbon aerogels once their densities are known. This paper reveals the relationships among permeability, pore size and density in carbon aerogels.
- Authors:
- Publication Date:
- Research Org.:
- Lawrence Livermore National Lab., CA (United States)
- Sponsoring Org.:
- USDOE; USDOE, Washington, DC (United States)
- OSTI Identifier:
- 7177095
- Report Number(s):
- UCRL-JC-108831; CONF-920402-54
ON: DE92019574
- DOE Contract Number:
- W-7405-ENG-48
- Resource Type:
- Conference
- Resource Relation:
- Conference: Material Research Society spring meeting, San Francisco, CA (United States), 27 Apr - 2 May 1992
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; CARBON; PERMEABILITY; FOAMS; GELS; CORRELATIONS; DENSITY; EQUATIONS; POROSITY; SIZE; COLLOIDS; DISPERSIONS; ELEMENTS; NONMETALS; PHYSICAL PROPERTIES; 360606* - Other Materials- Physical Properties- (1992-)
Citation Formats
Kong, F M, Hulsey, S S, Alviso, C T, and Pekala, R W. Determination of the permeability of carbon aerogels by gas flow measurements. United States: N. p., 1992.
Web.
Kong, F M, Hulsey, S S, Alviso, C T, & Pekala, R W. Determination of the permeability of carbon aerogels by gas flow measurements. United States.
Kong, F M, Hulsey, S S, Alviso, C T, and Pekala, R W. 1992.
"Determination of the permeability of carbon aerogels by gas flow measurements". United States.
@article{osti_7177095,
title = {Determination of the permeability of carbon aerogels by gas flow measurements},
author = {Kong, F M and Hulsey, S S and Alviso, C T and Pekala, R W},
abstractNote = {Carbon aerogels are synthesized via the polycondensation of resorcinol and formaldehyde, followed by supercritical drying and pyrolysis at 1050{degree}C in nitrogen. Because of their interconnected porosity, ultrafine cell structure and high surface area, carbon aerogels have many potential applications, such as in supercapacitors, battery electrodes, catalyst supports, and gas filters. The performance of carbon aerogels in the latter two applications depends on the permeability or gas flow conductance in these materials. By measuring the pressure differential across a thin specimen and the nitrogen gas flow rate in the viscous regime, we calculated the permeability of carbon aerogels from equations based upon Darcy's law. Our measurements show that carbon aerogels have apparent permeabilities on the order of 10{sup {minus}12}to 10{sup {minus}10} cm{sup 2} for densities ranging from 0.44 to 0.05 g/cm{sup 3}. Like their mechanical properties, the permeability of carbon aerogels follows a power law relationship with density and average pore size. Such findings help us to estimate the average pore sizes of carbon aerogels once their densities are known. This paper reveals the relationships among permeability, pore size and density in carbon aerogels.},
doi = {},
url = {https://www.osti.gov/biblio/7177095},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Apr 01 00:00:00 EST 1992},
month = {Wed Apr 01 00:00:00 EST 1992}
}