New Directions in Materials Science and Technology: Two- Dimensional Crystals

New Directions in Materials Science and Technology: Two-

Dimensional Crystals

Antonio H. Castro Neto

Graphene Research Centre

Worldwide investment in Graphene

European Union ~ USD$ 1,400 Million (?) USA ~ USD$ 50 Million

South Korea ~ USD$ 300 Million Singapore ~ USD$ 100 Million United Kingdom ~ USD$ 80 Million

~ 500 Million souls (2.8)

~ 300 Million souls (0.2)

~ 60 Million souls (1.3)

~ 50 Million souls (6)

~ 5 Million souls (20)

GRAPHENE RESEARCH CENTRE

S$ 100 Million ~ USD$ 80 Million - in 5 years

Visit:

www.graphenecenter.org

People

Antonio Castro Neto Physics, NUS

Yuan Ping Feng Physics, NUS Andrew Wee

Physics, NUS

Li Baowen Physics, NUS Kian Ping Loh

Chemistry, NUS

Hyunsoo Yang EE, NUS Peter Ho

Physics, NUS

Barbaros Oezyilmaz Physics, NUS

Yu Ting Physics, NTU

Vitor Pereira Physics, NUS Kostya Novoselov

Physics, NUS

Andre Geim Physics, Manchester

Nuno M. R. Peres Physics, NUS

Richard Kwok Wai Onn ST Kinetics

Lay-lay Chua Chemistry, NUS

Miguel Cazallila NUS, Physics

XPS/UPS UHV-STM

HREELS GLOVE BOX

EQUIPMENT

Clean Room

Class 100/1000

Theory Group

800 nodes IBM Computer Cluster

Modeling and Simulation of Structural

and Electronic Properties of 2D-Crystals

Research Lines and Collaborative Framework

Experiment



Magneto- transport



Optics



Raman



ARPES (SSLS)



TEM



STM



SEM



AFM

Applications & Devices



Growth (CVD, MBE)



Micro-fabrication



Patterning



Assembly

Theory



Modeling



Ab-initio



Molecular Dynamics



In-house HPC cluster

What about Graphene ?

5 µm

Graphene has been produced since the pencil was invented

in England in 1564 !

Human beings have been making money with Graphene since the 16th

century !

From 1564 to 2004 !

Plus some nanotechnology…

2 µ ^m

SiO

Si

Au contacts

graphite

optical image

SEM image

design

contacts and mesa

Graphene: leading the way in material science and technology

The 2010 Nobel Prize in Physics

Growth on SiC

Berger et al., J. Phys. Chem. B, 2004, 108 (52)

Exfoliation

chemically remove the substrate

CHEMICAL EXTRACTION

Kong ‘09

FIRST DEMONSTRATED Kong et al, Nanolett 2009 on Ni Hong, Ahn et al, Nature 2009 on Ni

Ruoff et al, Science 2009 on Cu

epitaxially grown monolayers

graphene-on-Si wafers

uniform; no multilayer regions;

few cracks; µ >5,000 cm ² /Vs

S. Seo (Samsung 2010)

B. H. Hong et al, Nature Nanotech. 2010

Summary of Electronic and Structural Properties

Dirac electrons Semi-metal

Phonons

High optical phonon frequencies K = Spring constant ~ 50 eV/A

Flexural modes

κ = bending rigidity ~1 eV

 Thinnest material sheet imaginable…yet the strongest! (5 times stronger than steel and much lighter!)

 Graphene is a semimetal

 Superb heat conductor

 Very high current densities (~10⁹ A/cm²)

 Easily transferrable to any substrate

Characterisitic Silicon AlGaAs/

InGaAs

InAlAs/

InGaAs SiC AlGaN/

GaN Graphene

Electron mobility at 300K (cm²/V·s) 1500 8500 5400 700 1500-2200 > 100,000

Peak electron velocity (×10⁷ cm/s) 1.0 (1.0)

1.3 (2.1)

1.0 (2.3)

2.0 (2.0)

1.3

(2.1) 5-7

Thermal conductivity (W/cm·K) 1.5 0.5 0.7 4.5 >1.5 48.4-53

Superlative Properties of Graphene

Graphene: Unprecedented transport properties

Graphene shows the highest carrier mobility of any known material

Unprecedented carrier mean free paths (~µm’s at room temperature) enable new

device architectures

Detection of individual gas molecules adsorbed on graphene

F. Schedin, A. K. Geim, S. V. Morozov, E. W. Hill, P. Blake, M. I. Katsnelson & K. S. Novoselov Nature Mater 6 (9): 652–655.

Hype or Hope ?

Miniaturization down to 1 nm : a few benzene rings Graphene Quantum Dots

Fine Structure Constant Defines Visual Transparency of Graphene

R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, N. M. R. Peres, A. K. Geim Science 320: 1308.

Transparent, Conductive Graphene Electrodes for Dye-Sensitized Solar Cells

Xuan Wang, Linjie Zhi, and Klaus Müllen Nano Letters 8 (1): 323.

Graphene-Based Ultracapacitors

Meryl D. Stoller, Sungjin Park, Yanwu Zhu, Jinho An and Rodney S. Ruof Nano Lett 8 (10): 3498.

Graphene-Based Single-Bacterium Resolution Biodevice and DNA Transistor:

Interfacing Graphene Derivatives with Nanoscale and Microscale Biocomponents

Nihar Mohanty and Vikas Berry Nano Letters 8: 4469–76

Graphene and Mobile Ions: The Key to All-Plastic, Solution-Processed Light-Emitting Devices

Piotr Matyba, Hisato Yamaguchi, Goki Eda, Manish Chhowalla, Ludvig Edman and Nathaniel D. Robinson ACS Nano, 2010, 4 (2), pp 637–642

Rapid Sequencing of Individual DNA Molecules in Graphene Nanogaps

Henk W. Ch. Postma

Nano Lett., 2010, 10 (2), pp 420–425

ULTRAFAST PHOTODETECTORS

h e

n-type doping

metal

p-type doping

metal graphene

Avouris, Nature Photo 2010

ballistic transport

of photo-generated carriers in built-in electric field

~2% conversion

due to high transparency of graphene

ρ ~40Ω/□ transparency ~90%

µ ~5,000 cm

/Vs

Hong, Nature 2009; Nature Nanotech. 2010

SUBSTITUTE FOR ITO

GRAPHENE:

conductive & transparent

flexible:

sustains strain >10%

TOUCH SCREENS

graphene electrodes liquid crystal

active layer

transparent polymer film

bendable & wearable

SKKU-Samsung 2010

BROADBAND SATURABLE ABSORBERS

STARTUPS

@ Singapore & Cambridge non-linear opacity:

graphene is more

transparent at high powers

from far-infrared to UV

~10 fs response

ultra high-f

analogue transistors;

HEMT design

Manchester, Science ’04

-100 -50 0 50 100

V

(V)

ρ (k Ω )

0 2 4 6

SiO

Si graphene

US military programs:

500 GHz transistors on sale by 2013 years

demonstrated (IBM & HRL 2009):

~100 GHz even for low µ & long channels

Y. Lin (IBM)

3 µm

ballistic transport on submicron scale,

high velocity,

great electrostatics, scales to nm sizes

THz Transistors

production within 3 years: from 0 to >100 ton pa low-quality graphene (multilayers)

ANY APPLICATION WHERE

CARBON NANOTUBES OR GRAPHITE

ARE CONSIDERED

BUT can be BETTER

• both sides bind

• monolayers cannot cleave

any further

Graphene

Take home lesson

is NOT the end of the road !

Graphene

Take home lesson

is the beginning of an exploration!

Graphene

2D Crystals

K.S. Novoselov, D. Jiang, T. Booth, V.V. Khotkevich, S. V. Morozov, & A.K. Geim. Two Dimensional

Atomic Crystals. PNAS 102, 10451-10453 (2005).

Manganites

Titanates

LiCoO2

Phosphonates FePS

Vitor M. Pereira (vpereira@nus.edu)

New Routes for 2D Crystal Growth and Tailoring

Exfoliation Chemical Functionalization

CVD Growth Strain Engineering

MBE

Intercalation

1

Platforms

Huang et al, arXiv:

1009.4714v1

Graphene suspension obtained from sonication of graphite

• Electronically dirty; Structurally poor

• Mass Production Cost: Low

• Printed Electronics

CVD Graphene : growth on metal

• Electronically OK ; Structurally OK

• Mass Production Cost: Medium Price

• Flexible Electronics Single Crystal Graphene

• Electronically great; Structurally great

• Mass Production Cost: ?

• High End Electronics

Graphene Oxide

TAILOR MADE CHEMISTRY ON GIANT POLYAROMATIC PLATFORM

(GRAPHENE OXIDE)

Atomically Thin Films (ATF)

Free-standing graphene films

GO film by Langmuir-Blodgett assembly

Solution process  density control

Composites

Casting G/Nafion Spin-coating G film Vacuum filtration

Large Scale Production: From Graphite to Graphene

Vitor M. Pereira (vpereira@nus.edu)

Our “gastronomy”...

= = = =

2D Crystals

Electronic Circuits

Electro actuators

Chemical and Bio Sensors

Fuel Cell

Supercapacitors

OLED Solar Cells

Photo-sensors IR Filters

Flexible Electronics

Platform for Applications

Summary



Paraphrasing Isaac Newton we can say that we are still in the infancy of a broad field and diverting

ourselves with graphene, a material that looks more interesting than ordinary, whilst a great field of 2D crystals lay all undiscovered before us.

Thank you !

Local Organization Chair:

Prof. Hong-Jun GAO, CAS (hjgao@iphy.ac.cn)

The 4 ^th International Conference on

Recent Progress in Graphene Research

October, 2012, Beijing, China