graphene nanoribbons
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Presentation topic: Graphene Nanoribbons
Presented to: Rethwan Faiz Course name: Power System Analysis Section: [G]
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Presentation members
Presented by:
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SL Name I.D1 Waleed, Khaled bin 14-26027-1
2 Hossen, MD. Saddam 13-24244-2
3 Hossain, MD. Anowar 13-24191-2
4 Mozammel, S. M. Mahmud 14-25942-1
Outlines
GrapheneCarbon nanotubes (CNT)Graphene nanoribbons (GNR)Comparison between CNT and GNRSynthesis methods of GNRsApplications of GNRsOp amp circuit using CNTFET
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Graphene
Graphene is a one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice
The name ‘graphene’ comes from graphite + -ene = graphene
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Molecular structure of graphene
Properties of Graphene
pure substance, orderly structure based on tight, regular, atomic bondingGraphene is believed to be the strongest material yet discoveredHas high thermal conductivityCan conduct electricity very wellIs very light and transparentSheets of Graphene are impermeable
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Graphene is the basic structural element of some carbon allotropes including… Graphite Charcoal Carbon Nanotubes Fullerene
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Carbon Nanotubes (CNT)Carbon nanotubes (CNT) are basically graphene sheets rolled up in a certain direction.“Chiral vector” or “chirality” describes how a graphene sheet is rolled up to form CNT.CNT might be metallic or semiconducting, depending on its chirality.Carbon nanotubes are strong, they are not brittle.They can be bent, and when released, they will spring back to their original shape.
Graphene Nanoribbons (GNR)
also called nano-graphite ribbonscarbon based materialone-dimensional structures with hexagonal two dimensional carbon latticesa derivative of GrapheneGraphene ribbons were introduced as a theoretical model by Mitsutaka Fujita
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Properties of GNR
GNR inherits almost all the attractive properties of the carbon nanotube and graphene.Has additional benefit of a tunable band gapZigzag & Armchair GNRs have metallic or semiconducting electronic properties that depends on the width of the nanoribbon.
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Rolling of a Carbon nanotube (CNT) from a graphene sheet
Cutting of a graphene nanoribbon (GNR) from a sheet of graphene
Synthesis methods of GNRs
The structure and physical properties of GNRs vary significantly depending on the synthesis method. The methods are: cutting from graphene using lithography bottom-up synthesis from polycyclic moleculesunzipping of carbon nanotubes (CNTs)
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Applications of GNRs
Light emitting diodesP-N junctionsSchottky diodesField effect transistorsConductive electrodesSolar cell systemsField effect transistors
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Comparison between two types of material used inTransistors of Fig 1 and Fig 2
Table 1: Set of CNT’s Diameters Used for the Op Amp Design
where "a" is the carbon to carbon atomic distance and it isequal to 1.42 angstrom
Normal 7-99 angstrom transistor has a height of 0.65 cm and a diameter of 0.60 cm
It can be concluded that diameter of Transistor is greatly reduced with usage of CNT material.
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