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May 20-21, 2019 | Vienna, Austria
Biomaterials and Nanomaterials &
Materials Physics and Materials Science
2
nd
International Conference on
Journal of Materials Science and Nanotechnology | Volume 3
Giant dielectric response and low dielectric loss in PbTiO
3
grafted CaCu
3
Ti
4
O
12
ceramics evaluated by impedance spectroscopy
Ali Rajabtabar
and
Ommeaymen Sheikhnejad
AC
2
T research GmbH, Austria
T
here is an ever-increasing tendency to employ
Electrochemical Impedance Spectroscopy (EIS) as a
strong tool to characterize thin films or ceramic layers
demonstrating electrical properties in Tribology. In this
regard, colossal dielectric materials with reasonable
energy storage and dielectric loss are on the core interest
of potential applications in sustainable energy industry.
In this study, PbTiO
3
(PT) was coated on the surface of
CaCu
3
Ti
4
O
12
(CCTO) particles via sol-gel method to enhance
the characteristics of grain boundary and interface towards
efficient application in Capacitors and Supercapacitors.
The X-ray diffraction (XRD) pattern of CCTO/PT ceramics
represents the PT phase exists mainly at the interface
between the CCTO grains. The field-emission scanning
electron microscopy (SEM) images captured from the
fracture surfaces confirm the grains were formed in cuboid-
like taking regular form with an increase in sintering time.
The line scan Energy-Dispersive X-ray Spectrometry (EDS)
result demonstrates that PT are slightly substituted in Cu
site of CCTO structure. EIS data demonstrates an enhanced
dielectric constant in low frequency with low dielectric
loss in high frequency for the grafted CCTO composite
ceramics (CCTO/PT composite ceramics with the PT
weight concentration of 10%) over the entire frequency
range. The dielectric loss for the CCTO-30% and -50% PT
samples is abruptly decreased to a value of ~0.0013 at 100
kHz. These observations were attributed to the change in
characteristics of grains and grain boundaries where the
insulating properties of the grain boundaries are improved
following the addition of PT.
Speaker Biography
Ali Rajabtabar is Scientist in AC
2
T research GmbH where is responsible
for data analysis as an experimental materials physicist in the pool of
advanced chemical analysis. He graduated in applied physics
(B.Sc./M.
Sc., Iran) and after 5+years of doing research and teaching physics,
he joined Harbin Institute of Technology to pursue his PhD degree in
materials physics and chemistry, while he enhanced the characteristics
of interface and grain boundary of CCTO based composite ceramics.
After a postdoctoral research in China, he moved to Austria as a guest
researcher working in ZONA-JKU Linz to learn and employ spectroscopic
ellipsometry. Then, as a senior research fellow he was doing EIS
measurement, modeling and data analysis on Li-ion battery project
of Keysight Technologies GmbH. He could publish even with diverse
research background in materials physics. Since his PhD, his focus was
placed on energy storage device and materials with growing challenges
towards industrial application.
e:
ali.rajabtabar@ac2t.at