| Attributs | Valeurs |
|---|
| type
| |
| Is Part Of
| |
| Subject
| |
| Title
| - Distribution of Carbon Nanotube Sizes from Adsorption Measurements and ComputerSimulation
|
| has manifestation of work
| |
| related by
| |
| Author
| |
| Abstract
| - The method for the evaluation of the distribution of carbon nanotube sizes from the static adsorptionmeasurements and computer simulation of nitrogen at 77 K is developed. We obtain the condensation/evaporation pressure as a function of pore size of a cylindrical carbon tube using Gauge Cell Monte CarloSimulation (Gauge Cell MC). To obtain the analytical form of the relationships mentioned above we useDerjaguin−Broekhoff−deBoer theory. Finally, the pore size distribution (PSD) of the single-walled carbonnanohorns (SWNHs) is determined from a single nitrogen adsorption isotherm measured at 77 K. We neglectthe conical part of an isolated SWNH tube and assume a structureless wall of a carbon nanotube. We findthat the distribution of SWNH sizes is broad (internal pore radii varied in the range 1.0−3.6 nm with themaximum at 1.3 nm). Our method can be used for the determination of the pore size distribution of the othertubular carbon materials, like, for example, multiwalled or double-walled carbon nanotubes. Besides theapplicable aspect of the current work the deep insight into the problem of capillary condensation/evaporationin confined carbon cylindrical geometry is presented. As a result, the critical pore radius in structurelesssingle-walled carbon tubes is determined as being equal to three nitrogen collision diameters. Below that sizethe adsorption−desorption isotherm is reversible (i.e., supercritical in nature). We show that the classicalstatic adsorption measurements combined with the proper modeling of the capillary condensation/evaporationphenomena is a powerful method that can be applied for the determination of the distribution of nanotubesizes.
|
| article type
| |
| is part of this journal
| |
