Graphene Is The Cutting Edge Material

The figure depicts the excitation of an electron into the conduction band thus leaving a hole in the valence band. An electron-hole pair is called an exciton, and the natural physical separation between them is called the excitonic Bohr radius and is characteristic of each material. Thus when a semiconducting material approaches a size nearing its Bohr excitonic radius, the exciton is said to be confined within the particle and is called quantum

In 1779, Carl Wilhelm Scheele showed another allotrope of carbon graphite, which were known as a form of lead in early times. He found out that graphite was almost identical to charcoal except a small admixture of iron, and when it oxidized with nitric acid, it gave out “aerial acid” (carbon dioxide). In 1786, the French scientists Claude Louis Berthollet, Gaspard Monge and Vandermonde confirmed that graphite was mostly carbon by oxidizing with oxygen in the same way

Graphene synthesis usually utilise a method called exfoliation, which is defined as taking the outermost layer of graphite. There are three major types of exfoliation: chemical, mechanical, and thermal. The paper mainly focuses on chemical and mechanical exfoliation for graphene synthesis, which are the methods with highest number of experiments done.

A single layer of graphene does not create significant photoresponsivity, however, with two layers and a tunnel barrier in between, the top layer becomes electrically charged and transfers this response to the bottom layer as seen in Figure 2. This anomaly is known as a photogating effect and it produces a unique photoresponsivity over an extensive spectral range (Zhong 1). It is capable of absorbing 2.3% of white light in just one layer of graphene. The charge that it creates in the top layer is amplified and these charged electrons tunnel through the insulating barrier performing a quantum tunneling effect.

What is graphene? According to Merriam-Webster, graphene is defined as “an extremely electrical conductive form of elemental carbon that is composed of a single flat sheet of carbon atoms arranged in a repeating hexagonal lattice

Buckminsterfullerene, also known as “buckyball” is composed of 60 carbon atoms arranged in twenty hexagons and twelve pentagons, with a carbon atom at each vertex of each polygon and a bond along each polygon edge. It is insoluble in water, except its hydrated form. Hydrated buckyballs have a dense, stable shell that is composed of water molecules. Scientist use C60 in nanotechological applications, because of its high heat resistance and electrical

It is currently used to manufacturer sporting goods and electronic components. Scientists tout graphene as the next silicon. The material is one million times thinner than paper and harder than diamonds, while conducting 200 times more electricity than silicon – a tremendous implication for the electronics industry. These advances come at a hefty price, but researchers at Caltech have discovered an improved manufacturing process for the material. Once researchers refine this process, manufacturers may also use the material for goods such as solar power and surface

Thus, it is reasonable to expect more layers of graphene on nickel and less layers graphene on copper.

Different structural arrangements in the carbon atoms determine the outcome of the mineral. Diamonds are the hardest mineral; they are formed under a covalent bond which is very strong. Graphite on the other hand is one of the softest; it is held with a softer bond. Despite the difference in structure, both of these minerals are made from the same substance, pure carbon.

Each carbon atom is covalently bonded (sp2 hybridized) to three other carbon atoms in a hexagonal array, leaving one free electron per each carbon atom. Each hexagon in the graphene sheet exhibits two pi-electrons, which are delocalized allowing for the efficient conduction of electricity. A single layer of graphite is called grapheme. This material displays extraordinary electrical, thermal and physical properties. Graphene is technically a non-metal but is often referred to as a quasi-metal due to its properties being like that of a semiconducting material and allowing it to display high electron mobility at room temperature.

Graphite is a form of carbon which is an element. In graphite, the carbon atoms are joined together and arranged in layers. The links between the carbon atoms in the layer are strong, but the links between the layers are weak. The layers easily slip over each other. That's why graphite in a pencil is soft and you can see a mark when you write with it on paper.

Graphene is easy to make you only need Scotch tape and some pencil lead (carbon is not lead it is graphite). It is one of the most versatile elements and is in all forms of steel. Due to graphite being so soft it is a great lubricant and can be bought in a very fine powder for that application. Diamonds are one of the hardest material. Diamonds have found applications in jewelry to tools and equipment. The best tools you can buy have micro diamonds inserted into the metal of the tools. Diamond drill bits are able to drill into hardened metal without breaking or severely disfiguring the bits. However if you heat diamonds up to much they will be oxidized into carbon dioxide. Fires make micro diamonds that almost immediately burn up. The structural difference of these two forms are interesting. The graphite has a hexagonal structure, and the diamond has a square crystalline structure which accounts for its hardness. Since carbon is a group 4a element, meaning it has two inner electrons and four outer and needs four or to give four electrons to get its perfect form, and most bonds of carbon are hexagonal or like a tree with branches coming off from the carbon. Carbon has the highest number of possible bonds of all of the elements, which is why it is the basis of life and organisms are able to be so different.

Graphene is a form of carbon which has recently been receiving a great deal of attention. Some have come to call it “the wonder material” due to its many extraordinary properties. Although isolated in 2004, graphene's properties had been calculated decades earlier. It consists of a single layer of carbon atoms arranged in a hexagonal lattice. A single sheet of graphene is stronger than steel and yet remains very flexible, retaining all of its properties despite being bent and unbent multiple times. It is able to sustain extremely high electric current densities, is impermeable to all gasses, has a thermal conductivity double that of diamond and a very high electron mobility at room temperature. It is also easily chemically functionalized,

Boron nitride (BN) is a lab-grown binary compound consisting of equal number of boron (B) and nitrogen (N) atoms. BN crystallizes either as a hexagonal layered structure or as a tetrahedral linked structure, similar to that of graphite and diamond

We have now discussed the two extremes in electronic materials; a conductor, and an insulator we will now move to a material that lies in between these two, a semiconductor. The