This document discusses polymeric materials used in organic solar cells. It explains that organic solar cells use organic polymers and small molecules to absorb light and transport charges. Common donor polymers mentioned include phthalocyanine and poly(3-hexylthiophene), while acceptor examples provided are perylene, perylene-3,4,9,10-tetracarboxylic dianhydride, phenyl-C61-butyric acid methyl ester, and buckminsterfullerene. The document outlines the charge transfer process in organic solar cells and advantages of using polymeric materials, such as low cost and flexibility. Hazards and properties are also noted for some mentioned materials.
2. Organic Photovoltaic Cells
Organic photovoltaic
cells are solar cells
that utilize organic
polymers and small
molecules as the
active layer for light
absorption and
charge transport
http://www.solarcell.net.in/2
3. Organic Photovoltaic Cells
Solar cells are
designed using a p-
n junction with
both n and p-type
materials such that
the free holes and
electrons flow in
opposite directions,
producing a direct
current.
http://www.solarcell.net.in/3
4. The Steps for the Charge
Transfer
1) Excitation on donor
2) Excitation delocalized on a donor-acceptor
complex
3) Charge-transfer initiated.
4) Charge separation.
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6. Advantages of Polymeric
Materials
Compared to silicon structures, organic materials
have several advantages:
1) Low cost of the technology
2) Possible to achieve fully flexible structures,
3) Relatively low voltages.
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7. Polymeric Materials
Materials having a delocalized electron
system can absorb sunlight, create
photogenerated charge carriers, and transport
these charge carriers.
Organic solar cells generally focuses either on
solution processable organic semiconducting
polymers.
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12. 1. Phthalocyanine
Unsubstituted
phthalocyanines
strongly absorb light
between 600 and
700 nm, thus these
materials are blue or
green.
Substitution can shift
the absorption
towards longer
wavelengths,
changing the color
from pure blue to12
16. 1. Perylene
C20H12
Molar mass: 252.31 g
mol−1
Melting Point: 276-
279 °C
S. Güneş, H. Neugebauer, Conjugated Polymer-Based Organic Solar Cells, 2007
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17. 1. Perylene
The
perylene molecule
consists of
two naphthalene mole
cules connected by a
carbon-carbon bond
at the 1 and 8
positions on both
molecules.
All of the carbon
atoms in perylene
are sp2 hybridized.S. Güneş, H. Neugebauer, Conjugated Polymer-Based Organic Solar
Cells, 200717
18. 1. Perylene
It or its derivatives
may be carcinogenic
Do not breathe dust
Avoid contact with
skin
Avoid contact with
eyes
.
http://en.wikipedia.org/wiki/Perylen
e
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19. 1. Perylene
It has an absorption
maximum at 434 nm.
http://en.wikipedia.org/wiki/Perylen
e
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23. 3. Phenyl-C61-butyric acid methyl ester
“PCBM”
It is a more practical
choice for an electron
acceptor when
compared with
fullerenes because of
its solubility
in chlorobenzene.
This allows for
solution processable
donor/acceptor mixes,
a necessary property
for "printable" solar
cells.23
24. 4. Buckminsterfullerene “C60”
C60
Molar Mass: 720.64 g
mol−1
Density: 1.65 g/cm3
Melting Point:
sublimates at ~600 °C
S. Güneş, H. Neugebauer, Conjugated Polymer-Based Organic
Solar Cells, 2007
24
25. 4. Buckminsterfullerene “C60”
The C60 molecule is
extremely stable,
being able to
withstand high
temperatures and
pressures.
S. Güneş, H. Neugebauer, Conjugated Polymer-Based Organic
Solar Cells, 2007
25
26. References
S. Gunes, H. Neugebauer, Conjugated Polymer-
Based Organic Solar Cells, 2007
A. Moliton1, R. Hiorns, Review of electronic and
optical properties of semiconducting π-conjugated
polymers: applications in optoelectronics, 2004
A. Facchetti, π-Conjugated Polymers for Organic
Electronics and Photovoltaic Cell Applications,
Northwestern University, 2011
www.wikipedia.com
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