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Volume 4
Nano Research & Applications
ISSN: 2471-9838
Page 96
JOINT EVENT
August 16-18, 2018 | Dublin, Ireland
&
12
th
Edition of International Conference on
Nanopharmaceutics and Advanced Drug Delivery
25
th
Nano Congress for
Future Advancements
Nano Congress 2018
&
Nano Drug Delivery 2018
August 16-18, 2018
Nano Res Appl 2018, Volume 4
DOI: 10.21767/2471-9838-C3-015
Sub-oxide passivation of silicon nanoparticles produced by mechanical attrition
David Moweme Unuigbe
University of Cape Town, South Africa
T
he presence of native oxide on the surface of silicon nanoparticles is renowned for constraining charge transport on the
surfaces. Studies carried out using scanning electron microscopy (SEM) shows that the particles in the printed silicon
network have a wide range of shapes and sizes. High-resolution transmission electron microscopy reveals that the particle
surfaces are dominated by the (111)- and (100)-oriented planes which stabilizes against further oxidation of the particles.
X-ray absorption spectroscopy (XANES) and X-ray photoelectron spectroscopy (XPS) measurements at the O 1s-edge have
been utilized to study the oxidation and local atomic structure of printed layers of silicon nanoparticles which were milled
for different times. XANES results reveal the presence of the +4 (SiO
2
) oxidation state which tends towards the +2 (SiO) state
for higher milling times. Si 2p XPS results indicate that the surfaces of the silicon nanoparticles in the printed layers are only
partially oxidized and that all three sub-oxide, +1 (Si
2
O), +2 (SiO) and +3 (Si
2
O
3
), states are present. The analysis of the change
in the sub-oxide peaks of the silicon nanoparticles shows the dominance of the +4 state only for lower milling times.
david.unuigbe@hotmail.com