If you take an inorganic material like a mixed oxide cerium-zirconium.
(1) May we say that there is a natural limit in the SSA (m2/g), e.g. 200 m2/g?
My understanding is that there is a relationship between porosity and SSA. May we state that due to the limitation of the porosity, there is a limitation of the SSA?
(2) if the SSA is measured by the BET method, what is the limit of the method in terms of SSA?
Thank you !!
It easy calculate this limit. For example for graphene this limit is equal 1720 m2/g.
I saw samples of carbon black with a specific surface area close to 103 m2/g. It is necessary to take into account that the measured specific surface area (nitrogen adsorption method) is experimental data based on a physical model. But reality is not always exactly the same with the model.
Dearest Denis Morel >>>
as you know the surface area can be found fro BET technique and will give you depending on the desorption adsorption nitrogen and also with loop of hydrolysis so like in aerogel silica they reached to 998 SA and with carbon black with a specific surface area close to 103 m2/g and that also depend on the model of ASAP and method .
You may say that there is a theoretical limit in systems with known structure. For example, the theoretical surface area of graphene 2630 m2/g, not 1720 (it is easy to do this calculation). This is not considering edge effects, which would increase the surface area.
About your second point, you must study the BET method and its assumptions. Then you will notice that the method is created for a non-porous surface. Check the assumption in the well-written wikipedia page: https://en.wikipedia.org/wiki/BET_theory
Perhaps you can calculate the adsorption isotherm for your system (if crystalline) by computer simulation (GCMC method) and obtain the maximum surface area.
It is usually considered that nanotechnologists work with the diameter of nanoparticles starting from 1 nm. Therefore, the specific area of such a powder or a porous body with such a size can be considered maximum. There may be clusters of atoms and molecules of smaller size
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You may say that there is a theoretical limit in systems with known structure. For example, the theoretical surface area of graphene 2630 m2/g, not 1720 (it is easy to do this calculation). This is not considering edge effects, which would increase the surface area.
About your second point, you must study the BET method and its assumptions. Then you will notice that the method is created for a non-porous surface. Check the assumption in the well-written wikipedia page: https://en.wikipedia.org/wiki/BET_theory
Perhaps you can calculate the adsorption isotherm for your system (if crystalline) by computer simulation (GCMC method) and obtain the maximum surface area.
Please find the link below, I hope this may help you.
https://www.researchgate.net/post/Why_is_N2_used_in_specific_surface_area_measurement_by_BET
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