PAPER PRESENTATION ON<br />Application Of Graphene In Modern Electronics<br />Presented By-<br />ChinmayChepurwar<br />G.H Raisoni College Of Engineering<br />(An Autonomous Institute under UGC act 1956,affilated to RTMNU, Nagpur)<br />Department of Electronics Engineering <br />
Obtained from simple and abundant form of carbon </li></ul> graphite . <br /><ul><li>Thinnest ever material in the world.</li></li></ul><li>The Graphene<br />Electron microscopic image on Sio2 surface<br />
The inventers<br />Andre Geim and Konstantin Novoselov have shown that carbon in such a flat form has exceptional properties<br />Konstantin Novoselow and Andre Geim were awarded the 2010 Nobel Prize for physics.<br />
History<br /><ul><li>The theory behind the substance graphene was first explored by theoretical physicist Philip Wallace in 1947.
In 1960’s it was believed that physically graphene cannot exist abecause of thermodynamic unstability
Graphene in itself however wasn't discovered until 2004 in its full observable and testable form
Since then, in the past 6 years, scientists have discovered that the substance retains some amazing properties.
Single layers of graphite were previously (starting from the 1970s) grown epitaxially on top of other materials.
There have also been a number of efforts to make very thin films of graphite by mechanical exfoliation
A key advance in the science of graphene was brought by Andre Geim and Konstantin Novoselov at Manchester University
Scotch tape technique</li></li></ul><li>Structure of Graphene<br />Sheets of graphene are bonded by loose bond in graphite. These bonds are broken and sheets are isolated to form graphene. These isolated hexagonal sheets are graphene.<br />
Salientfeatures of the structure<br /><ul><li> 2D Hexagonal structure.
Mechanical</li></li></ul><li>Physical properties of Graphene<br /> Density- density of graphene 0.77 mg/m2. <br />Strength- With its breaking strength 42 N/m it is 1000 times stronger than steel.<br />Optical transparency- graphene is almost transparent with its ability of absorb just 2.3% of light falling on it.<br />Thinnest possible material<br />
Conductivity further can be increased by applying electric field.
electrical conductivity of sheets are 10 times that of copper.
Best known conductor till now</li></li></ul><li>Electronic properties<br />15,000 cm2V−1s−1<br />Graphene differs from most conventional three-dimensional materials.<br />.<br />Intrinsic graphene is a semi-metal or zero-gap semiconductor<br />Graphene has a remarkably high electron mobility at room temperature<br />The mobility is nearly independent of temperature between 10 K and 100 K<br /> Resistivity of the graphene sheet would be 10−6 Ω·cm.<br />Optical properties<br />it absorbs πα ≈ 2.3% of white light<br />Unexpectedlyhigh opacity for an atomic monolayer<br />This is "a consequence of the unusual low-energy electronic structure of monolayer graphene<br />It is further confirmed that such unique absorption could become saturated when the input optical intensity is above a threshold value<br />Due to this special property, graphene has wide application in ultrafast photonics<br /> <br />
Thermal properties<br />The near-room temperature thermal conductivity of graphene was recently measured to be between (4.84±0.44) ×103 to (5.30±0.48) ×103 Wm−1K−1. <br />Mechanical properties<br />As of 2009, graphene appears to be one of the strongest materials ever tested. <br />200 times greater than steel<br />Bulk strength is 130GPa<br />Graphene sheets, held together by van der Waals forces<br />
What makes Graphene different from others???<br /><ul><li> Unique structure.
Graphene chips.</li></li></ul><li>Solar cells<br /><ul><li> The large scale production of highly transparent graphene films by chemical vapour deposition three years ago. In this process, researchers create ultra-thin graphene sheets by first depositing carbon atoms in the form of graphene films on a nickel plate from methane gas. Then they lay down a protective layer of thermo plastic over the graphene layer and dissolve the nickel underneath in an acid bath. In the final step they attach the plastic-protected graphene to a very flexible polymer sheet, which can then be incorporated into a OPV cell (graphenephotovoltaics).
High transperancy will increase efficiency of solar cells</li></li></ul><li>GrapheneBiodevices<br /><ul><li>Graphene's modifiable chemistry, large surface area, atomic thickness and molecularly-gatable structure make antibody-functionalized graphene sheets excellent candidates for mammalian and microbial detection and diagnosis devices. The most ambitious biological application of graphene is for rapid, inexpensive electronic DNA sequencing. Integration of graphene (thickness of 0.34 nm) layers as nanoelectrodes into a nanopore can solve one of the bottleneck issues
Nanopore-based single-molecule DNA sequencing.</li></li></ul><li>Fabrication of electronic devices <br /><ul><li>Graphene when converted into nanoribbon and nanotubes will replace silicon as semiconducting material.
Due to its high electronic quality, graphene has also attracted the interest of technologists who see it as a way of constructing ballistic transistors. Graphene exhibits a pronounced response to perpendicular external electric fields, allowing one to build FETs.
Graphene has excellent properties to be a vital component of integrated circuits
Graphene transistors are conceivable and are ready to replace silicon transistors
In 2009 researchers demonstrated four different types of logic gates, each consisting of a single graphene transistor
It is capable of taking an incoming electrical signal of a certain frequency and an producing output signal that is a multiple of that frequency
A recent publication has described a process for producing gram-quantities of graphene, by the reduction of ethanol by sodium metal, followed by pyrolysis of the ethoxide product, and washing with water to remove sodium salts.</li></li></ul><li>POTENTIAL APPLICATIONS OF GRAPHENE<br /><ul><li> Single molecule gas detection
Graphene-based sensors could sniff out dangerous molecules
Nanogapsin graphene sheets may potentially provide a new technique for rapid DNA sequencing.</li></ul>Escherichia coli<br />
MAJESTIC FUTURE<br /><ul><li>Advancements in touch screens</li></ul>It is practically transparent and a good conductor<br />Stiffer-stronger-lighter plastics<br />When mixed into plastics, graphene can turn them into conductors of electricity<br />
In the future, satellites, airplanes, and cars could be manufactured out of the new composite materials.<br />The fastest growing problem facing chip engineers today can be solved <br />
Graphene at its best<br /><ul><li>Better sports equipment