Introduction
Graphene has received great mass media coverage since Geim and Novoselov published their foundlings about monocrystalline graphitic films in 2004, which won them the Nobel Prize in Physics in 2010. (Novoselov et al, 2004) It has been described as the wonder substance or super material by the mass media, not only because it is the thinnest material ever known and the strongest ever measured, but also due to its excellent electrical, thermal, mechanical, electronic, and optical properties. It has high specific surface area, high chemical stability, high optical transmittance, high elasticity, high porosity, tunable band gap, and ease of chemical functionalization which helps in tuning its properties (Geim et al, 2007) Moreover, graphene has a multitude of amazing properties such as half-integer room-temperature quantum Hall effect (Novoselov et al, 2007), long-range ballistic transport with almost ten times greater electron mobility than that of silicon, and availability of charge carriers that behave as massless relativistic quasi particle, known as Dirac fermions. (Geim et al, 2007) The outstanding electrical conductivity and the transparency and flexibility of graphene-based material have led to research and development of some future technologies, such as flexible and wearable electronics. In addition, graphene can also be used for efficient energy storage materials, polymer composites, and transparent electrodes. (Geim et al, 2007) This paper presents a
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brief overview on the structure and some properties of graphene, along with a presentation of graphene synthesis method and various applications.
Structure
Graphene refers to a single layer of graphite, with sp2 hybridized carbon atoms arranged in a hexagonal...
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The complete experimental procedure is available in the General Chemistry Laboratory Manual for CSU Bakersfield, CHEM 213, pages 20-22, 24-25. Experimental data are recorded on the attached data pages.
Graphene Oxide is single sheets containing defect sites arising from partial oxidation of the edge and basal plane and graphene is an atomically flat single layer of C-atoms with outstanding electrical, mechanical and photonic properties. Figure 1 below shows the structure of graphene oxide.
Carbon exists in different forms such as graphite, amorphous carbon, and diamond, among others. Its graphitic carbon has a hexagonal and crystalline structure that easily cleaves which in turn makes it a soft material and effective lubricant. Its widely occurrence in earth’s crust makes it one the most abundant elements. Carbon presents itself in different allotropes such as Graphene, fullerenes and carbon nanotubes. Some of these allotropes have proven to be conducting and others to be semiconducting depending on their chemical nature (Ramuz & et al, 2012). Because of the abundance of carbon, carbon- based materials can be produced cheaply and in large quantities. In addition, carbon exhibits electrical and optical properties
Schreuder, Jolanda A. H.; Roelen, Corné A. M.; van Zweeden, Nely F.; Jongsma, Dianne; van der Klink, Jac J. L.; Groothoff, Johan W.
Shyu, Y., Hong, F. (2001). Low-temperature growth and field emission of aligned carbon nanotubes by chemical vapor deposition. Materials Chemistry and Physics, 72, 223-227.
The chemistry of diamonds is very interesting. Diamonds are composed mainly of carbon. Carbon can also exist as graphite, in a carbon chain or as buckminsterfullerene. It never forms bonds and leaves unshared electron pairs. In graphite the carbon atoms form an sp2 bonds. In this type of bonding an electron of the s orbital jumps to the p orbital to complete the octet with the other carbon atoms. When this happens it causes the orbital to flatten and the result is one big lattice in a two dimensional plane (Oxtoby). These lattices are attracted to each other not bonded to each other in compounds of graphite. Although they are made of the same carbon the diamond compound is different because of the type of bonds. Each atom forms four directional sp3 bonds instead of the three resonating bonds in graphite. This allows the diamond to keep its tetrahedral shape. It is also what makes the diamond so hard. The tetrahedral sh...
In the individual layer of graphite , the carbon atoms are assembled to form an honeycomb lattice with a gap of about 0.142 mm, and the average distance between planes is 0.335 NM. Graphite are found in two forms, alpha (hexagonal) and beta (rhombohedra), which share a very similar physical properties. The hexagonal graphite form which can either be flat or distorted. The alpha form can be changed to the beta form through mechanical processing and the beta form regresses to the alpha form when it is subjected to heat above 1300 °C. “7”
Fullerenes are accepted as the fourth for of solid carbon after amorphous, graphite and diamond forms. Fullerene chemistry has provided a new dimension of aromatic and a new platform for discussion of mathematical techniques pertinent to large cages. They are basically, large carbon cage molecules. These fullerenes have attracted great interest a large number of physical and chemical properties. These properties of nanostructures strongly depend on this size, shape and chemical compositions. This property leads to very interesting and recent applications in medicinal chemistry, material science and nanotechnology. Functionalization, intercalation and doping by the addition of electron acceptors or donors are the way of modifying the properties of these nanostructures. Among these nanostructures carbon based nanomaterials such as nanotubes, nanocages, nanoshells,
The ultra-small thickness of graphene could significantly improve the pressure sensitivity of the FPI sensors. In addition, graphene has much better mechanical strength than other thin film materials including metal and silica and could bear a static pressure up to MPa.
In 2010 two Russian-born scientists pioneered and synthesized a form of “wonder material” that generates heat and electricity at faster speeds, copes with high temperatures, and is almost transparent. Graphene is arranged in a flat hexagon lattice (like microscopic chicken wire) and is one atom thick two-dimensional 〖sp〗^2 bonded carbon. It is the world’s thinnest and strongest material, which can be manufactured into a plethora of provisions that can be used for next generation technology, such as planes, satellites, cars, and computers. However, uses of the material can be expensive and difficult to manufacture for mass production, which is why many of us today do not have access to graphene or use it for various applications in technology in day-to-day life. Graphene is a newly developing material, which is under scrutiny and scientific study in order to integrate it simply and effectively into everyday life.
Alford, Terry L., L. C. Feldman, and James W. Mayer. Fundamentals of Nanoscale Film Analysis. New York: Springer, 2007. Print.
Expo 2020 in Dubai, is set to be a very impactful event that will bring minds together to find solutions to global issues. The miraculous multi-functional material graphene will surely be featured in this world fair and it will definitely play a huge role in the future of not only the UAE, but also the entire world.
Plontke, R. (2003, March 13). Chemnitz UT. TU Chemnitz: - Technische Universität Chemnitz. Retrieved April 1, 2014, from http://www.tu-chemnitz.de/en/
A schematic configuration of the problem is illustrated in Figure 1. As can be seen in this figure, a double layer graphene sheet is covered by two ZnO piezoelectric layers. The thicknesses of graphene and piezoelectric layer are distinct and denoted by and , respectively. The interaction between graphene layers is modeled by Vdw force. The whole system surrounded by Pasternak foundation. Magnetic and electric field are applied to graphene and piezoelectric layers, respectively. Moreover, a biaxial force applied to the GSs. Before keeping on, it must be noted that the system shown in Figure 1 is divided into two systems. System 1 is considered upper piezoelectric and graphene layers, and system 2 is considered the lower ones.
Graphite is another form of carbon. It occurs as a mineral in nature, but it can be made artificially from amorphous carbon. One of the main uses for graphite is for its lubricating qualities. Another is for the "lead" in pencils. Graphite is used as a heat resistant material and an electricity conductor. It is also used in nuclear reactors as a lubricator (Kinoshita 119-127).