1. Graphene The theory of graphene was first put forth in 1947 by P.R. Wallace, but it was not until 2004 that graphene was produced in an observable and testable form. Graphene is basically a single atom layer of graphite, and is the thinnest material known to man with a thickness of 0.345 nanometers. It has the potential to revolutionize multiple industries including solar cell technology because of its unique properties. These properties include exceptional strength yet also flexibility, the best conductivity of any known material at room temperature, and durability as graphene cannot corrode or degrade. The structure of graphene, a two-dimensional crystal lattice, with the monolayer of carbon atoms packed tight in a hexagonal figure, is the reason for these properties. Graphene The theory of graphene was first put forth in 1947 by P.R. Wallace, but it was not until 2004 that graphene was produced in an observable and testable form. Graphene is basically a single atom layer of graphite, and is the thinnest material known to man with a thickness of 0.345 nanometers. It has the potential to revolutionize multiple industries including solar cell technology because of its unique properties. These properties include exceptional strength yet also flexibility, the best conductivity of any known material at room temperature, and durability as graphene cannot corrode or degrade. The structure of graphene, a two-dimensional crystal lattice, with the monolayer of carbon atoms packed tight in a hexagonal figure, is the reason for these properties. Non-Renewable Resources In 2013, 4,058 billion kilowatt-hours of electricity was produced in the U.S. alone. The vast majority of this production was from fossils fuels and other non-renewable resources like nuclear power. These resources are running out and will not always be available. Oil and gas are projected to be gone within fifty years while coal will only last twenty years longer than that. In addition to running out, these sources harm the Earth’s atmosphere when they are used. Fossil fuels emit carbon dioxide leading to “the greenhouse affect,” which negatively affects Earth’s climate. A renewable and sustainable source of energy, such as solar technology, must be developed into a reliable source. Non-Renewable Resources In 2013, 4,058 billion kilowatt-hours of electricity was produced in the U.S. alone. The vast majority of this production was from fossils fuels and other non-renewable resources like nuclear power. These resources are running out and will not always be available. Oil and gas are projected to be gone within fifty years while coal will only last twenty years longer than that. In addition to running out, these sources harm the Earth’s atmosphere when they are used. Fossil fuels emit carbon dioxide leading to “the greenhouse affect,” which negatively affects Earth’s climate. A renewable and sustainable source of energy, such as solar technology, must be developed into a reliable source. Photovoltaic Technology Photovoltaics is the direct conversion of light into electricity at the atomic level. Photovoltaic cells or solar cells harness the photoelectric effect, the observation that certain materials’ electrons will begin moving when exposed to light producing a small current. This effect only occurs with certain elements and compounds, which is why silicon and indium are used in current solar cell technology. Indium is very rare and, therefore, expensive as is the silicon refinement process. Because of this, solar cells are expensive and not available to or practical for most people. Graphene could change this as it possesses the properties needed to replace expensive materials and increase the efficiency of solar cells. Photovoltaic Technology Photovoltaics is the direct conversion of light into electricity at the atomic level. Photovoltaic cells or solar cells harness the photoelectric effect, the observation that certain materials’ electrons will begin moving when exposed to light producing a small current. This effect only occurs with certain elements and compounds, which is why silicon and indium are used in current solar cell technology. Indium is very rare and, therefore, expensive as is the silicon refinement process. Because of this, solar cells are expensive and not available to or practical for most people. Graphene could change this as it possesses the properties needed to replace expensive materials and increase the efficiency of solar cells. Electricity Generation by Energy Source (2013) Non-Renewable Energy 87% Renewable Resources 13% Coal39%Hydropower6% Natural Gas27%Wind4.4% Nuclear19%Biomass1.7% Petroleum2%Solar0.23% Other0%Other0.67% THE INTEGRATION OF GRAPHENE INTO PHOTOVOLTAIC SYSTEMS FOR CLEAN AND RENEWABLE ENERGY William Pezzuti and Julian Mandzy Graphene Integrated into Photovoltaic Cells 1.Graphene replacing indium2. Graphene and the rest of the solar cell 3. Sustainability 1.Graphene replacing indium 2. Graphene and the rest of the solar cell 3. Sustainability -Indium is used in solar cells as a transparent electrode - University of Cincinnati researchers have found that adding graphene- The problem with graphene is the inability to currently Graphene is also transparent and highly conductive flakes to certain parts of solar cells has increased their performance mass-produce quality graphene -Graphene is more durable than indium threefold- There are promising methods of production such -Graphene can match or even outperform indium as it allows - Researches at the MIT are experimenting with ways to use graphene as chemical reduction of graphene oxide and chemical more wavelengths of light to pass through throughout an entire solar cell, eliminating the need for silicon. In vapor deposition, they just need to be perfected -Graphene can be produced artificially, which would eliminate theory, this new solar cell could be 1,000 times more efficient than a- If graphene could be mass-produced, it would be the costly mining and use of rare, non-renewable indium silicon based cell extremely sustainable as would graphene solar cells and sustainable energy Graphene Integrated into Photovoltaic Cells 1.Graphene replacing indium2. Graphene and the rest of the solar cell 3. Sustainability 1.Graphene replacing indium 2. Graphene and the rest of the solar cell 3. Sustainability -Indium is used in solar cells as a transparent electrode - University of Cincinnati researchers have found that adding graphene- The problem with graphene is the inability to currently Graphene is also transparent and highly conductive flakes to certain parts of solar cells has increased their performance mass-produce quality graphene -Graphene is more durable than indium threefold- There are promising methods of production such -Graphene can match or even outperform indium as it allows - Researches at the MIT are experimenting with ways to use graphene as chemical reduction of graphene oxide and chemical more wavelengths of light to pass through throughout an entire solar cell, eliminating the need for silicon. In vapor deposition, they just need to be perfected -Graphene can be produced artificially, which would eliminate theory, this new solar cell could be 1,000 times more efficient than a- If graphene could be mass-produced, it would be the costly mining and use of rare, non-renewable indium silicon based cell extremely sustainable as would graphene solar cells and sustainable energy “It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran Wrap.”- Researchers at Columbia University's Fu Foundation School of Engineering. Scientists believe graphene could become important in many aspects of our lives, it may just take some time. Nobel Prize winning scientist Andre Geim said, “Compare this situation with the one 100 years ago when people discovered polymers. It took some time before polymers went into use in plastics and became so important in our lives.” Projected depletion of coal, oil, and gas SiO 2(s) +C (s) →Si (l) +CO 2(g) Si (s) +3HCl (g) →SiHCl 3(g) +H 2(g) SiHCl 3(g) +H 2(g) →Si (s) +3HCl (g) The reactions used to produce a very pure form of silicon called semiconductor grade silicon. The whole process is costly, requires heating of up to 1500-2000 o C, and the final reaction alone takes 200-300 hours. There are also harmful byproducts such as CO 2.