Ion induced structural changes in graphite
Document Type
Conference Proceeding
Publication Date
10-2-2019
Abstract
We studied ionization-induced changes in the bonding of highly oriented pyrolytic graphite (HOPG) from sp2 (graphitic) to sp3 (amorphous or diamondlike) using MeV ion beams with varying degrees of surface energy deposition via ionization (electronic stopping power). This study allows us to better understand phase changes in ionizing environments as a function of electronic stopping power, as well as possibly provide a path to precise functionalization of materials such as graphene. Coupons of HOPG were bombarded with He, Si, and C ions at energies designed to produce ionization from 32 to 277 eV/Å, and the surfaces were examined using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and 3D laser microscopy. As expected, we observed the transformation of graphitic sp2 bonding to amorphous or diamondlike sp3 bonds, with the extent generally dependent on the amount of ionization energy deposited, a transformation which may be explained by ion-induced excitation followed by rapid thermal quenching. Significant amount of surface disruption and cracking, however, indicated that the results could have been significantly affected by thermal swelling and damage to the material.
Recommended Citation
Demaree, J. D.; Miller, L. S.; Luo, Z.; and Ila, D., "Ion induced structural changes in graphite" (2019). College of Health, Science, and Technology. 1056.
https://digitalcommons.uncfsu.edu/college_health_science_technology/1056