How exact can we determine the specific surface area of porous materials?
The specific surface area of powders and porous solids is usually described with the BET theory, however especially in the micropore range we should cast a critical spotlight on the term “surface area” on an atomic scale. On one hand, this will be in reference to the “real surface”, which incorporates irregularities and impurities of any given porous material. On the other hand it is also in relation to other representations of a surface area determined by a variety of analytical instruments employing the method of physisorption such as the 3P meso 400. This will be especially important during the determination of micropores. Furthermore the apparent contradiction, that surface area analysis in microporous materials is theoretically questionable but a sample characterisation based on it is very useful from a practical point of view, needs to be considered.
