Detalles de publicación
PP 014075
Neutron bombardment of single wall carbon nanohorn (SWCNH): DSC determination of the stored Wigner-Szilard energy
F. Cataldo
Istituto Nazionale di Astrofisica – Osservatorio Astrofisica di
Catania, Via S. Sofia 78, 95123 Catania, Italy
&
Actinium Chemical Research, Via Casilina 1626/A,
00133 Rome, Italy;
S. Iglesias-Groth
Instituto de Astrofisica de Canarias, Via Lactea s/n, 38200 La
Laguna, Tenerife, Spain;
Y. Hafez
National Center for Astronomy, KACST, P.O. Box
6086, Riyadh 11442, Saudi Arabia;
G. Angelini
Istituto di Metodologie Chimiche, CNR, Via Salaria Km 29,300,
00016 Monterotondo Stazione, Rome, Italy
Single wall carbon nanohorn (SWCNH) were
neutron-bombarded to a dose of 3.28
9
10
16
n/cm
2
. The
Wigner or stored energy was determined by a differential
scanning calorimeter and was found 5.49 J/g, 50 times
higher than the Wigner energy measured on graphite flakes
treated at the same neutron dose. The activation energy for
the thermal annealing of the accumulated radiation damage
in SWCNH was determined in the range 6.3–6.6 eV against a
typical activation energy for the annealing of the radiation-
damaged graphite which is in the range of 1.4–1.5 eV. Fur-
thermore the stored energy in neutron-damaged SWCNH is
released at 400–430
C while the main peak in the neutron-
damaged graphite occurs at 200–220
C. The radiation
damaged SWCNH were examined with FT-IR spectroscopy
showing the formation of acetylenic and aliphatic moieties
suggesting the aromatic C=C breakdown caused by the neuton bombardment.
neutron-bombarded to a dose of 3.28
9
10
16
n/cm
2
. The
Wigner or stored energy was determined by a differential
scanning calorimeter and was found 5.49 J/g, 50 times
higher than the Wigner energy measured on graphite flakes
treated at the same neutron dose. The activation energy for
the thermal annealing of the accumulated radiation damage
in SWCNH was determined in the range 6.3–6.6 eV against a
typical activation energy for the annealing of the radiation-
damaged graphite which is in the range of 1.4–1.5 eV. Fur-
thermore the stored energy in neutron-damaged SWCNH is
released at 400–430
C while the main peak in the neutron-
damaged graphite occurs at 200–220
C. The radiation
damaged SWCNH were examined with FT-IR spectroscopy
showing the formation of acetylenic and aliphatic moieties
suggesting the aromatic C=C breakdown caused by the neuton bombardment.