Behaviors of single CO2molecule on pentagon at carbon nanotube tip observed by field emission microscopy

Abstract

AbstractBehaviors of a single CO2 molecule on a clean pentagon at a tip of multiwall carbon nanotube (MWNT) were investigated by field emission microscopy (FEM). A CO2 admolecule was recognized as a gourd‐shaped bright spot in an FEM image similar to the nitrogen admolecule previously reported. The shape of bright spot reflected an adsorption state that the molecular axis was parallel to substrate pentagon. The CO2 admolecule moved between five steady adsorption sites which were reflected in the geometrical five‐fold symmetry of pentagon. From these experimental results, we propose an adsorption site model for a CO2 admolecule on a clean pentagon. By an Nd:YAG pulse laser irradiation, the CO2 admolecule successfully desorbed without any damage of the substrate pentagon whereas the end‐atoms are oxygen. This suggests that a CO2 molecule on a pentagon is physisorbed and chemically inert for surfaces of MWNT. Copyright © 2008 John Wiley & Sons, Ltd.