Conference Session (B5)
Paper #6193
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University of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper
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THE USE OF GRAPHENE AS A PHOTOVOLTAIC MATERIAL
Karl Sewick, kws13@pitt.edu, 10AM Mahboobin, Thomas Dastalfo, tjd46@pitt.edu, 4PM Mahboobin
Revised Proposal —
Our conference paper will discuss the advantages of the
use of graphene as a photovoltaic material instead of the
current use of various compounds of silicon in the structure
of solar panels. Graphene is a good material for
photovoltaics because of its low electrical resistance,
compound structure, and its ability for doping to improve its
absorption spectrum/coefficient. This paper will mainly
compare graphene to silicon and their use in a photovoltaic
system. These issues are mainly centered around the
efficiency of energy collection from a solar panel.
Solar panels function by converting energy from the sun
in the form of photons into an electric current using a
semiconducting material that is doped on both sides in order
to polarize the semiconductor. To each side of the
semiconductor an electrode is attached. When photons strike
the positive side of the semiconductor, their energy is
absorbed by the semiconductor. The absorbed energy excites
electrons across the semiconductor from the positive to the
negative side, and these electrons are repelled from the
negative side and forced into a wire. This movement of
electrons into the wire induces an electric current [1].
The prospect of achieving all of our energy needs through
clean solar power is certainly a topic worth discussion and
research. In fact, the National Academies of Engineering has
declared “making solar power economical” one of the grand
engineering challenges of the 21st century [2]. The main
problems they have cited is that solar cells need to become
more efficient, cheaper, and we need to have a better method
of storing energy. We believe that using graphene as a
photovoltaic material may be the answer to making solar
cells more efficient.
This is not a method of energy production that comes
without any ethical dilemmas however. The main ethical
dilemmas surrounding solar energy production is to where do
we route all of this power? Who deserves it more, the big
cities or the fledgling rural communities that could benefit
from it massively [3]?
The general structure of graphene allows for more
efficient solar panels, relating to its electrical properties
which are conducive to carry electricity. Graphene is a 2-d
sheet of carbon atoms which is one atom thick. This pi bond
between carbons acts as a conducting bond for the electrons
University of Pittsburgh Swanson School of Engineering 1
Submission Date
to travel in across the structure increases the conductivity of
the material [4]. Therefore, graphene as a material has the
lowest resistivity of any material, about 37% less resistant
than silver [5]. This is an issue with silicon because of how
poor of a conductor it is. Another problem with silicon is with
its color, being a black color, some of the light will only heat
up the material without providing any additional energy. This
decreases efficiency because the temperature and resistivity
of materials follows a direct relationship. Pure graphene
absorbs poorly but can be altered to be a 54% better
absorber than silicon [6].
REFERENCES
[1] Institute of Physics. ”How do solar cells work?”.
http://www.physics.org/article-questions.asp?id=51
[2] (2016).National Academy of Engineering. “Make Solar
Energy Economical”
.http://www.engineeringchallenges.org/challenges/solar.aspx
[3] (2011).“Ethical Issues in Use Of Solar Energy
Researchomatic”. http://www.researchomatic.com/EthicalIssues-In-Use-Of-Solar-Energy-68394.html
[4] Joseph Bunch.(2008). Mechanical and Electrical
Properties of Graphene Sheets.(45-47)
[5] University of Maryland.(2008). “Electrons Can Travel
Over 100 Times Faster In Graphene Than In Silicon,
Physicists Show”. ScienceDaily
[6] Koppens Thongrattanasiri. Garcia de Abajo. (2013).
“Total light absorption in graphene”
ANNOTATED BIBLIOGRAPHY
F. Brunetti, G. Ulisse, M. Dianetti, G. Susanna, G. Innaccone,
G. Fiori, O. Martin, D. Neumaier, R. Puicervert, D. Lordan,
M. Burke, A Quinn, M. Schimidt, P. Lugli. (2015 July).
“Doped and textured graphene as electrode for organic solar
cells”. 2015 IEEE 15th International Conference on
Nanotechnology.
(Conference
Publication).
http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=73
88666&newsearch=true&queryText=graphene%20cost
Karl Sewick
Thomas Dastalfo
This conference paper was presented at the IEEE 15th
International Conference on Nanotechnology in Rome, Italy.
This paper analyzes the using graphene electrodes to develop
low-cost, flexible, large area solar cells. This paper also
analyzes research in which n and P doped graphene films
were transferred onto glass to produce solar cells. This paper
will be helpful to our paper by providing experimental data of
the efficiency of graphene used in solar cells to incorporate
into our paper.
This document is relevant to our topic and gives us data to
support our claims, and is also from a well respected source.
G. Hwang, S. Haliyo, S. Regnier. (2010, April). “Infraredphotovoltaic properties of graphene revealed by electroosmotic spray direct patterning of electrodes”. Micro & Nano
Letters. vol:5. issue:2. pp.140-145 (Online Article).
http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=54
57366&newsearch=true&queryText=graphene%20manufactu
ring%20cost
This article was published in Micro & Nano Letters, a
publication that publishes short research papers presenting
research on micro- and nanoscale science. This article
analyzes a method of using a robotically controlled electroosmotic spray to create optoelectronic devices directly onto
the surface of graphene in a cost efficient way. These
manufactured graphene optoelectronic devices have great
photoelectric properties in infrared wavelengths. This will be
useful in our paper by illustrating a method in which
graphene can create an electric current from not only visible
wavelengths of light but also infrared wavelengths.
J. Bunch.(2008). Mechanical and Electrical Properties of
Graphene
Sheets.
Cornell
University.(pg.
45-47).
(Dissertation)
http://www.mceuengroup.lassp.cornell.edu/sites/mceuen/files
/publications/Thesis_Bunch.pdf
This dissertation, from the graduate department of Cornell
University, discusses the difference between graphite and
silicon in their electrical properties. The dissertation also
discusses the fundamental characteristics of graphene and its
construction. The paper also helps to describe the structure of
graphene. These specifications are critical to our paper by
helping us understand the properties of graphene and its
comparison to silicon.
F.H.L. Koppens, S. Thongrattanasiri, F.J. Garcia de Abajo.
(2013). “Total light absorption in graphene”. Physical
Review Letters. (Online Article).
http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.108.0474
01
This article, from the American Physical Society, details
discoveries in the improvements of the absorption of
graphene. This article states that graphene can be perfectly
absorbent when doped, ordered in a periodic array of
nanodisks, and placed on a dielectric. This is crucial to our
paper because of the importance on the absorption light for
solar panels, which would improve efficiency in the panels.
G. Fiori, P. Paletti, R. Pawar, G. Iannaccone, G. Ulisse, F.
Brunetti. (2015 July). “Improving the efficiency of organic
solar cells with graphene transparent electrode and light
management: a simulation study”. 2015 IEEE 15th
International Conference on Nanotechnology. (Conference
Publication).
http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=73
88915&newsearch=true&queryText=graphene%20solar%20e
fficiency
This conference paper was also presented at the IEEE 15th
International Conference on Nanotechnology in Rome, Italy.
This paper details how to improve the efficiency of organic
solar cells by as much as 30% by using graphene electrodes
instead of ITO transparent electrodes. This data was acquired
through simulations, and this data scales from the atomic
level up to the device level. This paper and data will help us
illustrate how graphene electrodes can dramatically increase
the efficiency of solar cells.
University of Maryland. (2008). “Electrons Can Travel Over
100 Times Faster In Graphene Than In Silicon, Physicists
Show”. ScienceDaily. (Online Article).
http://www.sciencedaily.com/releases/2008/03/08032409451
4.htm
This article, from ScienceDaily, a respected source for
current research discoveries, gives statistics on the resistance
of graphene as a material. This article fundamentally explains
the difference of resistivity of graphene compared to that of
copper, a low resistance metal. the article is very helpful to
our paper because of resistance being a limiting factor in the
current that we can produce from the photoelectric effect.
C. Huang, S. Yu, Y. Lai, G. Chi, and P. Yu. (2015).
"Efficiency Enhancement of Organic/GaAs Hybrid
Photovoltaic Cells Using Transparent Graphene as Front
Electrode,". IEEE Journal of Photovoltaics. vol.PP, no.99,
pp.1-6 (Online Article)
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=73
42873
This article is from the IEEE journal of Photovoltaics and
explains the possible use of graphene as a front electrode.
The source gives data on the use of doped graphene as the ptype semiconductor for the panel, with a dielectric below it,
and compares its efficiency to a generation two solar panel.
W. Wang, T. Li, Y. Wang. (2012). “Photovoltaic Response of
N-doped Graphene-based Photodetector”. IEEE 7th
International Conference on Nano/Micro Engineered and
Molecular
Systems.
(Conference
Publication) http://ieeexplore.ieee.org/xpl/articleDetails.jsp?
arnumber=6196714&newsearch=true&queryText=Graphene
%20photovoltaic
2
Karl Sewick
Thomas Dastalfo
This conference paper was presented at the IEEE 7th
International Conference on Nano/Micro Engineered and
Molecular Systems (NEMS) in Kyoto, Japan. This paper
analyzes the photovoltaic response that was found in an Ndoped graphene based photodetector with a metal-graphenemetal structure. The paper also covers how nitrogen atoms
are doped into the graphene and also, how once doped with
nitrogen the graphene displays semiconducting properties and
generates a photocurrent under light excitation. This paper
will help us to describe an effective way of doping graphene
in order to make it produce a current when struck with
photons.
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