An experimental study of melting of CCl4 in carbon nanotubes.
We report dielectric relaxation spectroscopy measurements of the melting point of carbon tetrachloride confined within open-tip multi-walled carbon nanotubes with two different pore diameters, 4.0 and 2.8 nm. In both cases, a single transition temperature well above the bulk melting point was obtained for confined CCl4. These results contrast with what was obtained in our previous measurements using carbon nanotubes with a pore diameter of 5.0 nm, where multiple transition temperatures both above and below the bulk melting point of CCl4 were observed. Our experimental measurements are consistent with our recent molecular simulation results (F. R. Hung, B. Coasne, E. E. Santiso, K. E. Gubbins, F. R. Siperstein and M. Sliwinska-Bartkowiak, J. Chem. Phys., 2005, 122, 144706). Although the simulations overestimate the temperatures in which melting upon confinement occurs, both simulations and experiments suggest that all regions of adsorbate freeze at the same temperature, and that freezing occurs at higher temperatures upon reduction of the pore diameter.
Jazdzewska
Monika
M
Institute of Physics, Adam Mickiewicz University, Umultowska 85, 61-614, Poznan, Poland.
Hung
Francisco R
FR
Gubbins
Keith E
KE
Sliwinska-Bartkowiak
Malgorzata
M
D002251:Carbon Tetrachloride / Q000737:chemistry*; D025802:Electric Capacitance; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010316:Particle Size; D013057:Spectrum Analysis; D044366:Transition Temperature
D037742:Nanotubes, Carbon; D002251:Carbon Tetrachloride