Monday, September 1, 2008

Graphene pioneers follow in Nobel footsteps/Pavlosky - Carbon Flakes - 2000

01 Sep 2008

Two physicists from The University of Manchester who discovered the world’s thinnest material have scooped a major award for their work.

Professor Andre Geim FRS and Dr Kostya Noveselov of the Centre of Mesoscience and Nanotechnology have been awarded the prestigious Europhysics Prize for discovering graphene - and also their subsequent work to reveal its remarkable electronic properties.

Graphene is a one-atom thick gauze of carbon atoms resembling chicken wire. This incredible new material has rapidly become one of the hottest topics in materials science and solid-state physics.

Presented since 1975, the Europhysics Prize is one of the world’s most prestigious awards for condensed matter physics.

Many winners have subsequently been awarded the Nobel Prize in recognition of their achievements, including the last year Nobel Laureates Albert Fert, Peter Grünberg and Gerhard Ertl.

The Europhysics Prize recognizes recent work by one or more individuals, which, in the opinion of the European Physical Society, represents scientific excellence.

The 2008 Award was presented at the 22nd General Conference of the EPS Condensed Matter Division in Rome.

Aside from the prestige, Prof Geim and Dr Novoselov will share a cash prize of Euros 10,000.

Since the discovery of graphene in 2004, Prof Geim and Dr Novoselov have published numerous research papers in prestigious journals such as Science and Nature, which have demonstrated the exquisite new physics for the material and its potential in novel applications such as transistors just one atom thick and sensors that can detect just a single molecule of a toxic gas.

Prof Geim said: “To receive this award is a great honour. We have been working very hard and putting in long hours for the last five years. Hundreds of other researchers have now joined us in studying graphene.

“But still we have not yet explored even a tip of the iceberg. Graphene continues to surprise us beyond our wildest imagination.

“It works like a magic wand – whatever property or phenomenon you address with graphene, it brings you back a sheer magic.

“A couple of years ago, I was rather pessimistic about graphene-based technologies coming out of research labs any time soon. I have to admit I was wrong. They are coming sooner rather than later.

“In ten years time I believe the word graphene will be as widely known to the public as silicon.”

Source

United States Patent 6,819,034
Pavlovsky November 16, 2004

Carbon flake cold cathode

Abstract

A field emission cold cathode utilizes a film of carbon flake field emitters deposited thereon. The carbon flakes may exhibit rolled edges, but are still sufficient to provide improved field emission characteristics. A cold cathode using such carbon flake field emitters can be utilized to produce afield emission flat panel display, which can be implemented for use with a computer system.


Inventors: Pavlovsky; Igor (Austin, TX)
Assignee: SI Diamond Technology, Inc. (Austin, TX)
Appl. No.: 09/642,955
Filed: August 21, 2000


BACKGROUND INFORMATION

Carbon flake is a carbon material with a graphitic structure. It can be as thin as one or more layers of sp.sup.2 -bonded carbon atoms (graphite layers), and can be very long in two other dimensions. The length of a flake can be on the order of microns, whereas the thickness is on the order of nanometer or tens of nanometers. Thus, the aspect ratio for this material is very high. A flake, by its nature, is a system of ordered or turbostratic graphite layers. Carbon flakes fall into a class of nanostructured carbon materials. The flakes can be grown by several methods that fall into the following categories: 1. DC Glow Discharge. This method involves a direct current glow discharge between two electrodes in a gas environment. The plasma between the two electrodes is of the order of 1000.degree. C. or higher. This method produces carbon flakes along with other types of carbon materials such as carbon nanotubes. This method is used for depositing directly onto a substrate. 2. Thermal CVD (Chemical Vapor Deposition) Method. In this method, a carbon precursor gas and a substrate are heated to a temperature of 600.degree. C. and higher while thermal decomposition of the precursor is observed. The substrate has a catalyst on the working surface, which gives rise to growing carbon structures like carbon nanotubes and carbon flakes. A bias voltage can be used to make carbon nanostructures grow straight. This method is used for depositing directly onto a substrate.


Referring to FIG. 4, there is illustrated a cold cathode configured in accordance with the present invention. A substrate 101 has a conductor material 102 deposited thereon. Then carbon flakes 103-105 are grown on top of the conductor material 102. The carbon flake field emitters 103-105 can be grown by a plasma-assisted chemical vapor deposition ("CVD") method using a mixture of hydrogen (H.sub.2) and methane (CH.sub.4) or other hydrocarbon gas as a carbon precursor. The substrate 102 has a temperature of at least 400.degree. C., and is heated by a heater, or by adjacent plasma, or by hot carbon containing gas. The substrate 102 is cooled if its temperature is too high to form the flakes 103-105. During decomposition of carbon containing gas, the carbon atoms, or bonded carbon atoms, or carbon radicals assemble and form an sp.sup.2 -bonded carbon structure initiated on the substrate. The carbon radicals can further decompose leaving the carbon atoms bonded to the growing flake. The growth process occurs on the edges of the flakes 103-105 provided that flake is growing in lateral dimensions as new carbon atoms are bonded. This carbon structure 103-105 comprises the layers of sp.sup.2 -bonded atoms of carbon. The layers can be stacked together to form thicker flakes. During decomposition, gas species other than carbon may incorporate as defects in carbon structure. Such defects, as well as intrinsic defects of carbon structure may cause irregularities in this structure and, in turn, cause the flake bending.

What is claimed is:

1. An apparatus comprising: a substrate; a film of carbon flakes deposited on the substrate.

Source

2000 is way earlier than 2004! Let's give credit where credit is due.

emails:
1)
fromdonpat/donpatent/nanopatent
tokostya@manchester.ac.uk
dateMon, Sep 1, 2008 at 9:36 AM
subjectFwd: Geim, graphene and Pavlovsky and credit where credit is due
mailed-bygmail.com

Please show this to Prof Geim and ask him what he thinks. What do you think? I would have sent this to Geim but can't find an email address for him.

---------- Forwarded message ----------
From: donpat/donpatent/nanopatent <donpatent@gmail.com>
Date: Mon, Sep 1, 2008 at 9:14 AM
Subject: Geim, graphene and Pavlovsky and credit where credit is due
To: webteam@manchester.ac.uk


2)
fromKostya Novoselov
reply-toKonstantin.Novoselov@manchester.ac.uk
todonpat/donpatent/nanopatent
dateTue, Sep 2, 2008 at 9:29 AM
subjectRE: Geim, graphene and Pavlovsky and credit where credit is due


Dear Sir

I’m really grateful for the information about your patent on using turbostratic graphite for field emission cathode applications. I want to wish you a great success with it. Turbostratic graphite has been known for several decades and I’m glad that this interesting material will find its use in applications.

I would also like to draw your attention to several companies, which utilise similar idea in their products (for instance http://www.pfe-ltd.com/ ). I’m sure that you deserve some royalties there as well.

Sincerely yours

Kostya_____________________________________
Dr. Kostya Novoselov
School of Physics & Astronomy
Schuster Building
University of Manchester
Manchester M13 9PL
United Kingdom
Tel: +44-(0)161-275-41-19 (office)
Tel: +44-(0)161-275-42-41 (lab)
Fax: +44-(0)161-275-40-56
E-mail: kostya@manchester.ac.uk
Web: http://www.graphene.org
_____________________________________

3)
donpat/donpatent/nanopatent to Konstantin.Nov.

It's not my patent - it's my company's patent. What exactly is turbostatic graphite - I was under the impression that the patent referred to graphene flakes.

And did so at least before 2000, whereas your graphene development was ~ 2004.

Good luck with your claim to be the first.

I know PFE and they do not use graphene flakes.

(End of emails)

I looked for turbostratic graphite and graphene - this is of interest:
http://www-g.eng.cam.ac.uk/edm/Publications/pdf/Ferrari_PRL2006.pdf