Graphene: Production, Properties and ApplicationsPresented By: Ardalan Hayati Far

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Carbon allotropes

Carbon forms/

Hybridization

sp3

sp2 sp

sp3 - sp22

Carbon allotropes

• sp3

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The Darya-I-Nur Diamond Unit cell of the diamond cubic crystal structure

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Carbon allotropes

• sp

( C C )− ≡ − n

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Carbon allotropes

• sp3 - sp2

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Carbon allotropes• sp2

Graphite

Fullerene

Graphene

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Graphene and its descendants

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Production Techniques

• Exfoliation

• Epitaxy★ Silicon carbide

★ Metal substrates

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Production Techniques• Exfoliation

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Production Techniques• Exfoliation

Graphene on SiO2Graphene suspension in

chloroform11

Production Techniques• Epitaxy Metal substrate

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Production Techniques• Epitaxy Silicon carbide

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Properties

• Structure

• Mechanical

• Chemical

• Optical

• Thermal and thermoelectric

• Electronic

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Properties: Structure

TEM Optical micrograph

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Properties: Mechanical

Pressure strengh AFM

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Properties: Chemical

NO2 molecule on graphene surface17

Properties: Optical

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Properties: Thermal and thermoelectric

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Properties: Electronic

Why graphene is strange?

Electrons in graphene = Charge carriers

Electrons in graphene have zero effective mass.

For graphene we use Dirac equation! not Schrodinger equation.

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Properties: Electronic

Graphene lattice Band structure diagram

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Band structure diagramChemist Physicist

Localized electrons Delocalized electrons

MO Diagram Band Structure Diagram

Molecular Orbital Wavevector

Chemical bonding Potentials

Qualitative (Intuitive) Quantitative (Mathematical)

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Band structure diagram

Bloch function23

Band structure diagram: An example

The Band Structure of a 1D chain of H atoms

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Graphene Band Structure

High symmetry points25

Graphene Band Structure

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Graphene Band Structure

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Graphene Band Structure

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So What?!Graphene is a gapless semiconductor.

Graphene is a metal without overlapping.

Richard Feynman 29

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Applications

Visit this link:

http://www.graphene.manchester.ac.uk/future/

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Thanks for your attention

Questions?

Ardalan Hayati FarDey 1392