Determination of the space between closed multiwalled carbon nanotubes by GCMC simulation of nitrogen adsorption

Zeolite microporosity studied by molecular simulation

“…in which N (r, p) is the loading of adsorbed molecules at pressure p, ρ (in units of mmol/ml) is the saturation loading of Ar in pores of diameter r, P (r) is the pore size distribution in units of ml g −1Å−1 , α is the (dimensionless) affinity parameter (0.31 for Ar [53]), E 0 is the characteristic adsorption energy (kJ/mol), p 0 is the saturation vapor pressure, and n(r) is a constant that only depends on r. The total loading θ(p) of Ar in the zeolite is computed by [54,55,56,35,36],…”

“…These microscopic methods describe the guest-host system at a molecular level, in contrast to classical methods that are based on macroscopic thermodynamic assumptions. It has been shown that the application of theoretical and molecular simulation-based methods leads to a much more accurate pore size analysis over the complete micro and mesopore size range [34,35,36].…”

Simple model of adsorption on external surface of carbon nanotubes—a new analytical approach basing on molecular simulation data

“…Bundles were generated basing on triple-walled tube obtained from tubes (48,0), (40,0) and (32,0)-t_w3_048. Analogous boxes were applied previously (Furmaniak et al 2008a(Furmaniak et al , 2009a) Fig. 10 The comparison of experimental data (nitrogen at 77.3 K-circles) with obtained from fitting of the model proposed in this study (equations (7) and (10)) so large that the tubes behave almost independently, so the secondary porosity contains rather large pores, affecting the mechanism of adsorption by a small amount.…”

“…It should be noted that more and more complicated models reproducing the structure of real carbon nanotubes (i.e. from ideal cylinders (Arora et al 2004;Arora and Sandler 2005;Gauden et al 2009;Harris 2009;Khan and Ayappa 1998;Kotsalis et al 2004;Kowalczyk et al 2005;Maddox and Gubbins 1995;Müller 2008;Ohba and Kaneko 2002;Terzyk et al 2008;Zhang et al 2008) to bundles (Alain et al 2000;Arab et al 2004;Furmaniak et al 2008aFurmaniak et al , 2009aHarris 2009;Sandler 2003, 2004;Paredes et al 2003;Wongkoblap et al 2009;Yin et al 1999) and tubes with defects Sandler 2007a, 2007b;Furmaniak et al 2009a;Gauden et al 2009;Harris 2009;Terzyk et al 2008;Zhang et al 2008)) have been applied. On the other hand, despite the complex structure of carbon nanotubes confirmed by the analysis of experimental data (mutual position of nanotubes in the bundle, defects, an unavoidable by-products of a typical nanotube growth process i.e.…”

“…On the other hand, despite the complex structure of carbon nanotubes confirmed by the analysis of experimental data (mutual position of nanotubes in the bundle, defects, an unavoidable by-products of a typical nanotube growth process i.e. impurities, such as carbon-coated catalyst particles, graphitic and amorphous carbons, and other carbon nanomaterials (Harris 2009)) the evaluation of the pore-size distribution of carbon nanotube sizes from the static adsorption measurements and computer simulations of nitrogen adsorption at 77 K calculated for the separated nanotubes has been treated as the standard method (Furmaniak et al 2008a;Kowalczyk et al 2005;Zhang et al 2003). However, the above-mentioned simple procedure has been insufficient for some experimental data.…”