%0 Journal Article
%A Balzer, Christian
%A Cimino, Richard T.
%A Gor, Gennady
Y.
%A Neimark, Alexander V.
%A Reichenauer, Gudrun
%D 2016
%T Deformation of Microporous Carbons during N2, Ar, and CO2 Adsorption: Insight from the Density Functional
Theory
%U https://acs.figshare.com/articles/journal_contribution/Deformation_of_Microporous_Carbons_during_N_sub_2_sub_Ar_and_CO_sub_2_sub_Adsorption_Insight_from_the_Density_Functional_Theory/3509606
%R 10.1021/acs.langmuir.6b02036.s001
%2 https://acs.figshare.com/ndownloader/files/5576429
%K CO 2 Adsorption
%K CO 2 data
%K adsorption stress
%K Density Functional Theory
%K N 2
%K adsorbate diameter exhibit
%K Ar
%K micropore
%X Using the nonlocal
density functional theory, we investigate adsorption
of N2 (77 K), Ar (77 K), and CO2 (273 K) and
respective adsorption-induced deformation of microporous carbons.
We show that the smallest micropores comparable in size and even smaller
than the nominal molecular diameter of the adsorbate contribute significantly
to the development of the adsorption stress. While pores of approximately
the nominal adsorbate diameter exhibit no adsorption stress regardless
of their filling level, the smaller pores cause expansive adsorption
stresses up to almost 4 GPa. Accounting for this effect, we determined
the pore-size distribution of a synthetic microporous carbon by simultaneously
fitting its experimental CO2 adsorption isotherm (273 K)
and corresponding adsorption-induced strain measured by in situ dilatometry.
Based on the pore-size distribution and the elastic modulus fitted
from CO2 data, we predicted the sample’s strain
isotherms during N2 and Ar adsorption (77 K), which were
found to be in reasonable agreement with respective experimental data.
The comparison of calculations and experimental results suggests that
adsorption-induced deformation caused by micropores is not limited
to the low relative pressures typically associated with the micropore
filling, but is effective over the whole relative pressure range up
to saturation pressure.
%I ACS Publications