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.

1.
B. T.
Kelly
,
Physics of Graphite
(
Applied Science
,
London
,
1981
).
2.
J. F.
Ziegler
,
J. P.
Biersack
,
U.
Littmark
, “The Stopping and Range of Ions in Matter” (
Pergamon Press
,
1985
).
3.
J. C.
Lascovich
,
R.
Giorgi
,
S.
Scaglione
, “
Evaluation of the sp2/sp3 ratio in amorphous carbon structure by XPS and XAES
”,
Appl. Surf. Sci.
, Volume
47
, Issue
1
,
17
21
(
1991
).
4.
Y.
Mizokawa
, “
The C KLL first-derivative x-ray photoelectron spectroscopy spectra as a fingerprint of the carbon state and the characterization of diamondlike carbon films
“,
Jour. of Vac. Sci. & Tech. A
5
,
2809
(
1998
).
5.
A.
Mezzi
,
S. Kaciulis, “Surface investigation of carbon films: from diamond to graphite
”,
Surf. And Interface Analysis
, Volume
42
, Issue
6-7
(
2010
).
6.
Ziegler
JF
,
Biersack
JP
,
Ziegler
MD
.
The Stopping and Range of Ions in Matter
,
SRIM, 2013
. Actual website: http://www.srim.org. (
2013
)
7.
G.
Gawlik
,
P.
Ciepielewski
,
J. M.
Baranowski
,
J.
Jagielski
,
Surf. Coat. Tech.
306
,
2016
,
119
122
8.
J.
Liu
,
H. J.
Yao
,
Y. M.
Sun
,
J. L.
Duan
,
M. D.
Hou
,
D.
Mo
,
Z. G.
Wang
,
Y. F.
Jin
,
H.
Abe
,
Z. C.
Li
,
N.
Sekimura
,
Nucl. Instr. Meth. B
,
245
,
126
129
(
2006
).
9.
Andrea C.
Ferrari
,
Solid State Communications
143
,
47
57
(
2007
).
10.
R.J.
Nemanich
,
S.A.
Solin
,
Phys. Rev. B
,
20
,
392
(
1979
).
11.
R.P.
Vidano
,
D.B.
Fishbach
,
L.J.
Willis
,
T.M.
Loehr
,
Solid State Commun.
39
,
341
(
1981
).
12.
V.
Abidzina
,
I.
Tereshko
,
I.
Elkin
,
I.
Muntele
,
C.
Muntele
,
R. A.
Minamisawa
, and
D.
Ila
,
NIM B
Volume
257
, Issues
1–2
,
523
526
(
2007
).
13.
B.
Chhay
,
L.
Bowman
, and
D.
Ila
, “
Effects of Carbon Ion on Glassy Carbon Electrode as Chemical Sensor
”,
Mat. Res. Soc. Proc.
1204
(
2009
).
This content is only available via PDF.