Surface probe of single-walled carbon nanotubes irradiated by high-energy proton beams

Abstract

The AP-grade (higher than 80 % purity) single-walled carbon nanotubes (SWCNTs) were irradiated by proton beams with energies higher than 10 MeV. The physical properties of the surface were examined by using scanning electron microscope (SEM) and Raman spectroscopy (RS) for both the irradiated and the non-irradiated samples, and the subtle change in the local atomic arrangement of the irradiated samples was examined by using a gas adsorption technique. The Raman spectroscopy study demonstrated a fine modification in the bonding of carbons after proton irradiations while no substantial structural modification was measured by using electron microscopy. A series of Ar gas adsorption results measured below 77 K revealed a decreased number of isotherm steps after proton bombardment suggesting the creation of local surface defects.