solar technology using carbon nanotubes

1. Seminar (15EES86)
Presentation on
“Carbon Nanotubes in Solar Panel Technology”
Presented By
Dada khalandar
(2TG14EE009)
Under the Guidance of
Prof. Jagdeeshwar G. S. B.E., M. Tech.
Asst.Prof ,Dept. of E&EE ,TCE Gadag
Department of Electrical and Electronics Engineering
2019-20
S.T.S.K.K’s
TONTADARYA COLLEGE OF ENGINEERING
MUNDARGI ROAD, GADAG – 582 101

2. Contents
 Introduction
 Comparison between organic solar cells and carbon solar cells
 Carbon nanotubes and their Classification of nanotubes
 Material used in construction
 Construction and working of carbon solar cell
 Effect of carbon nanotubes on efficiency
 Properties of CNT’s
 Application and advantages
 Conclusion
 Reference

3. Introduction
 In today’s world with increase in population the demand for energy
is very high and major part of this demand is achieved by using
fossil fuels like oil ,natural gas and coal.
 Global energy problems, energy costs, green house effects, climate
change are the problems that drive the need for sustainable energy.
 Solar energy is the energy of future and is the solution to all these
problems. Photovoltaics and Concentrated solar power(CSP) are
the technologies used to convert solar energy to electricity.
 Solar panels of first generation and second generation are less
efficient and cost per watt is high.
 The research studies on third generation solar cells have efficiency
greater than 40%.These solar cells are made using carbon
nanotubes, graphene, solar inks .

4. 1.3 Comparison Between Organic Solar Cells and
Carbon Solar Cells
Carbon Solar Cells Organic Solar Cells
1. Made up of silicon and polymers. 1. made up of carbon deposits
2. Cost effective. 2.Potential to deliver high performance
at low cost.
3. Easily available for production. 3.Synthesis of carbon thin films is to be
done.
4. Fabrication is easy. 4. Fabrication is tough.
5. Efficiency of organic solar cells is
around 14-19%.
5. Efficiency of Carbon solar cells is 20-
30%.
6. Organic cells are corrosive. 6. Highly resistive to Corrosion.

5. Carbon nanotubes
 Carbon nanotubes (CNTs; also known as bucky tubes) are allotropes
of carbon with a cylindrical nanostructure. These cylindrical carbon
molecules have novel properties that make them potentially useful
in many applications in nanotechnology, electronics, optics and
other fields of materials science, as well as potential uses in
architectural fields. They exhibit extraordinary strength and unique
electrical properties, and are efficient thermal conductors.
 Nanotubes are members of the fullerene structural family, which
also includes the spherical bucky balls.
 Their name is derived from their size, since the diameter of a
nanotube is on the order of a few nanometers (approximately
1/50,000th of the width of a human hair), while they can be up to
18 centimeters in length .

6. CLASSIFICATION OF NANOTUBES
Carbon nanotubes are classified into
Single walled carbon nanotubes(SWCNT)
Multi walled carbon nanotubes(MWCNT)
Single Walled Carbon Nanotubes (SWCNT) Multi Walled Carbon Nanotubes (MWCNT)

7. MATERIALS USED INCONSTRUCTION
Carbon nanotubes(CNT’s)
 CNT’s are tubes made of pure carbon molecules having diameters
measured in nanometers .
 The chirality of the nanotube determines whether the tube is metallic
or semiconducting, optoelectric properties and diameter of the tube.
 The diameter of the nanotube has a corelation with the optical band
gap.
 The hexagonal array of atoms on the tube prohibit electrons from
diffusing through the wall. This characteristic forces the electrons to
travel down the axis of the tube, generating a very rapid and
efficient charge transport system.

8. MEH-PPV-CN
 The polymer being used in the active layer of the solar cell is Poly[2-
methoxy-5- (2ethylhexyloxy)-1,4-(1-cyanovinyl- enephenylene)],
which is abbreviated MEH-PPV-CN.
 MEH-PPV-CN is a light emitting polymer with peak emission
wavelength of 558nm and peak absorption at 405nm.
 MEH-PPV has applications in OFET’s, polymer light emitting
diode and pervoskite solar cells.

9. Construction of Carbon Solar Cell:
 In conventional solid-state photovoltaic cells three different tasks
are generally expected to be fulfilled simultaneously by the material.
 Light absorption to generate electric charge carriers, charge carrier
separation and charge transport to the electrodes.
 A mixture of a stable photoactive light absorbing dye molecule with
carbon nanotubes introduced to a conjugated polymer matrix to
perform these tasks.
 During this time a Charge separation at the interface, electron
transport through the carbon nanotube acceptors and hole transport
from the dye to the polymer backbone occur.

10. CNT’s in Carbon solar cell

11. Working
 Solar panels work on the principle of photovoltaic effect.
 Photovoltaic effect is generation of voltage and electric current in
material when expossed to light.
Working of carbon solar cell

12.  The electrons that are generated when the solar panels are
exposed to a stream of photons are transferred between the
different bands of energy inside the atom to which they are bound.
 The transition of the energy state of electrons takes place from
valence band to the conduction band, but within the material that
is used in the solar panels. This transfer of electrons makes them
accumulate in order to cause a build up of voltage between the two
electrodes.
 Series connections of solar cells in solar panels help add up the
voltage.

13. Effect of carbon nanotubes on efficiency
 A CNT based transparent electrode as an alternative to ITO has
improved the range of absorption from ultraviolet to near infrared
offering a wide wavelength.
 The power conversion efficiency(PCE) can be improved by 1.31%
using CNT/Si hetrojunction solar cells.
 BHJ solar cells with CNT can enhance a PCE upto 5%.
 N-doped mutiwall carbon nanotubes help in achieving highly
efficient polymer bulk hetrojunction solar cell.
 N-MWCNT increases the effieciency of the solar cell by 8.6%.

14. Properties of carbon nanotubes
 High thermal conductivity
 High electrical conductivity
 High tensile strength
 Low thermal expansion coefficient
 Chemical stability
 High mechanical strength
 Ideal semiconductors for solar technology

15. Applications
 Carbon Nanotube Composites in Photoactive Layer
 CNT’s in Dye-Synthesized Solar Cells
 Carbon Nanotubes as Transparent Electrodes
Advantages
 The efficiency of the system can be improved.
 They remain stable at ambience temperature about 1600F.
 The amount of the material to be used for the construction
will also be reduced.
 As the mobility of the electrons is more in the case of the CNT
the output voltage produced is drastically increased.

16. CONCLUSION
 It is a brief review of CNT applications in photovoltaics and the
design development of future generation’s solar cells. CNTs
support better sunlight absorption .
 The addition of 3rd generation technology to the solar industry is
one possible way to end energy crisis. With affordable, efficient,
environmentally friendly energy available and the effect of global
warming can be reduced.

17. References
[1] IETE Zonal Seminar “Recent Trends in Engineering & Technology” - 2017 Special
Issue of International Journal of Electronics, Communication & Soft Computing
Science and Engineering, ISSN: 2277-9477
[2] Science and Engineering, ISSN: 2277-9477 IETE Zonal Seminar “Recent Trends in
Engineering & Technology” - 2017 Special Issue of International Journal of
Electronics, Communication & Soft Computing.
[3] Hoppe, Sariciftci. “Organic Solar Cells: An Overview” J. Mat. Res. 19 (7) 1924-45,
2004.
[4] Huang, Houjin et al. “Relative Optical Absorption of Metallic and Semiconducting
Single- Walled Carbon Nanotubes.” J. Phys. Chem. B 110 4686-4690, 2006.
[5] Institute for Molecular Engineering, The University of Chicago, 5747 South Ellis
Avenue, Chicago, Illinois 60637, United States Center for Nanomaterials and
Chemical Reactions, Institute for Basic Science (IBS), Materials Science and
Engineering, KAIST,Daejeon 305-701, Republic of Korea

18. THANK YOU