Characterization of porosity in nanoporous carbons using scanning tunneling microscopy

Characterization of activated carbon fibers using argon adsorption

“…(10) and (11). The calculated isotherm is then modified by a uniform random error ranging from 0.5% to 1%.…”

“…These techniques can be grouped into direct and indirect methods. The direct method consists of high resolution transmission electron microscopy (HRTEM) [6,7] and scanning tunneling microscopy (STM) [8][9][10], which offers not only direct visualization but also quantitative characterization of the internal structure of nongraphitized carbons in terms of pore morphology and topology [11]. The direct method generally indicates that the micropore morphology of activated carbon fiber is slit-shaped [12][13][14], and more recently it has been shown to provide a good correlation with characterization by gas adsorption [6].…”

Structural characterization of polyetherimide‐based carbon molecular sieve membranes

“…techniques, such as scanning tunneling microscopy STM and Ž . atomic-force microscopy AFM , have made it possible to look at the surface of microporous materials in greater detail than it was ever possible before using electron microscopy tech-Ž niques Hoffman et al, 1994;Economy et al, 1995;Rao and . Sircar, 1996 .…”

Quantitative assessment of pores in oxidized carbon spheres using scanning tunneling microscopy

“…Transversal section analysis was used in previous works, [9][10][11][12] but the results depended closely on the section chosen and the area observed was very limited, contrary to the present method. This method seems to be very useful for the differentiation of pores from depressions and trenches in the STM images.…”

“…The last class constitutes the majority of an internal surface of an activated carbon, and they represent 90 to 95% of the total surface area. [9][10][11][12] It was, however, pointed out that a quantitative interpretation of STM images is not evident because the surface area scanned is small and it is very difficult to differentiate pores from other surface defects (contaminations, depressions, trenches, etc). This limit would appear to restrict the micropore filling of small molecules (N 2 , CO 2 , .…”