Hydrogen adsorption studies on single wall carbon nanotubes

Hydrogen adsorption data on as-grown and heat-treated single walled carbon nanotubes (SWNTs) obtained by a volumetric procedure using a Quantachrome Autosorb-1 equipment are presented. The amounts of hydrogen adsorbed at atmospheric pressure reach approximately 0.01 wt.% at 298 K and I wt.% at 77 K. The isosteric heat of adsorption has been calculated for both samples from H-2 equilibrium adsorption data at three temperatures, having initial values of 7.42 and 7.75 kJ mol(-1). Studies in porous structure by N-2 adsorption and density measurements in helium pycnometer are reported. (C) 2004 Elsevier Ltd. All rights reserved.