Growth and characterization of Graphene

Graphene, a single sheet of Carbon atoms arranged in a honeycomb lattice, has become the most promising material for the future. Graphene has been studied for long time from a theoretical point of view. After its isolation in 2004 experiments began and its properties revealed.
Due to its electrical, optical and mechanical properties, this 2D material can be used in many applications ranging from electronics to medicine. Such applications include, but are not restricted to, energy storage, optoelectronics, THz electronics, transparent conductors, artificial leaves, materials reinforcement, drug delivery, cell scaffolds, and many others.
In order to be able to use Graphene for such applications it is necessary to have a fast, reliable and cost-effective production method.
During the past ten years many methods have been applied for the synthesis and isolation of Graphene. Among them the most promising are the so-called physical vapor and chemical vapor deposition methods.
In this work we will first introduce Graphene and its physical properties. Then we will concentrate on the Characterization techniques used to investigate this material; in particular we will see how Raman spectroscopy is a non-destructive invaluable tool for Graphene identification and characterization. Scanning electron microscopy is also a very useful tool for imaging of Graphene and it will be also described.
The third part of the work is dedicated to a survey of the Graphene growth and isolation methods. In particular our work will focus on Graphene growth by carbon precipitation on thin film metals and, thus, the aspects of thin film deposition and crystallization will be reviewed.
Last, we will present the results obtained in the Surfaces, Thin films & Nanostructures laboratory in L’Aquila on Graphene growth on Ni thin films. The technique used carbon precipitation and subsequent recrystallization in Graphene on top of Ni after thermal annealing, using as carbon sources both solid amorphous carbon (deposited by flash evaporation) and gaseous CH4 precursor.
The as-grown Graphene shows a characteristic Raman spectrum. The presence of D and D’ peaks reveal its defective structure while 2D peak fitting shows few-layer Graphene, compatible with the values found in literature.