What is Graphene?

Carbon atoms arranged in honeycomb
structure forming graphene sheet

To understand what is graphene first we should be familiar with the structure of graphite. With our naked eye graphite looks bulk solid but actually it is made up of many layers stacked one up on another. Each of these individual layers are called graphene. Each of the graphene sheets is formed when carbon atoms are arranged in a honeycomb fashion as shown in fig.

  

     

Graphene is also called material with many of the superlatives. It is the strongest, most flexible and most transparent material. Due to these exciting properties there is global race to use graphene in day-to-day electronic devices. Theoretically graphene was predicted long ago but practically isolated quite recently (2004 AD). Ak Geim and Ks Novoselov were awarded Nobel Prize in physics for their discovery of graphene in 2010. I got a chance to have short talk with Mr. Novoselov during a conference in Tokyo last year. Graphene was first extracted from bulk graphite using scotch tape. For industrial application of graphene scotch tape method is not suitable as it produces graphene flakes of few milimetre only. For large scale production of graphene Chemical vapor deposition (CVD) method is widely used. In CVD method solid (like camphor) or gaseous  (like methane) precursor is detonated at high temperature on metallic substrate like Nickel or copper in presence of carrier gases like hydrogen and argon or their mixture. Schematic diagram of CVD is shown below.

In our lab we use solid precursor for producing graphene. Camphor is one of the precursors we are using currently. As we know camphor is derived from the plant it is environmental friendly and non- hazardeous compared to gaseous precursors like methane.

For further queries about the method of graphene synthesis on copper and Nickel foil following article can be taken as reference.

1) Influence of gas composition on the formation of graphene domain synthesized from camphor

http://www.sciencedirect.com/science/article/pii/S0167577X12016692

2) Synthesis of hexagonal graphene on polycrystalline Cu foil from solid camphor by atmospheric pressure   chemical vapor deposition

 http://link.springer.com/article/10.1007%2Fs10853-013-7514-3

Introduction to my research at NIT

My name is subash sharma and i'm currently phd student at nagoya institute of technology Japan.
My research interest are carbon materials like graphene, carbon nanotubes and so on. Papers published related to my research are :

1) Influence of gas composition on the formation of graphene domain synthesized from camphor
        S.Sharma, G.Kalita, R.Hirano, Y. Hayashi, M.Tanemura
                 Materials Letters 93, 258 (2013)

 2) Synthesis of graphene by surface wave plasma chemical vapor deposition from camphor
           G.Kalita, S.Sharma, K.Wakita, M.Umeno, Y. Hayashi, M.Tanemura
                      Physica status solidi (a)

3)  A photoinduced charge transfer composite of graphene oxide and ferrocene
            G.Kalita, S.Sharma, K.Wakita, M.Umeno, Y. Hayashi, M.Tanemura
               Phys. Chem. Chem. Phys., 2013,15, 1271-1274