Graphite is a mineral composed of stacked sheets of carbon atoms with a hexagonal crystal structure. It is the most stable form of pure carbon under standard conditions. Graphite is very soft, has a low specific gravity, is relatively non-reactive, and has high electrical and thermal conductivity.
Graphite occurs naturally in igneous and metamorphic rocks, where high temperatures and pressures compress carbon into graphite. Graphite can also be created synthetically by heating materials with high carbon content (e.g. petroleum coke or coal-tar pitch). The carbon-rich material is heated to 2500 to 3000 degrees Celsius, which is hot enough to "purify" the material of contaminants, allowing the carbon to form its hexagonal sheets.
Diamond and graphite crystal structures. Graphene would be a single layer of the graphite crystal structure.
Graphite is extremely soft and breaks into thin flexible flakes that easily slide over one another, resulting in a greasy feel. Due to this, graphite is a good "dry" lubricant and can be used in applications where wet lubricants (like lubricating oil) cannot.
Carbon has several other allotropes, or forms, that occur naturally, each with their own crystal structure. One form is graphene, which is a single layer of carbon atoms in a hexagonal pattern. Another well-known allotrope of carbon, are diamonds. Although also composed of pure carbon, diamonds are almost entirely different in their physical properties.
Uses
Uses
Graphite is used in a number of applications that require high temperatures and need a material that will not melt or disintegrate. Graphite is used to make the crucibles for the steel industry. Graphite is also used as a neutron moderator in certain nuclear reactors, like the Soviet RBMK, due to its ability to slow down fast-moving neutrons.
Other common uses of graphite include:
Pencil lead
Lubricant
Electrodes in batteries
Brake linings for heavy vehicles
What is Graphene
Graphene is a one-atom-thick layer of carbon atoms arranged in a hexagonal lattice. It is the building-block of Graphite (which is used, among others things, in pencil tips), but graphene is a remarkable substance on its own - with a multitude of astonishing properties which repeatedly earn it the title “wonder material”.
Graphene's properties
Graphene is the thinnest material known to man at one atom thick, and also incredibly strong - about 200 times stronger than steel. On top of that, graphene is an excellent conductor of heat and electricity and has interesting light absorption abilities. It is truly a material that could change the world, with unlimited potential for integration in almost any industry.
Potential applications
Graphene is an extremely diverse material, and can be combined with other elements (including gases and metals) to produce different materials with various superior properties. Researchers all over the world continue to constantly investigate and patent graphene to learn its various properties and possible applications, which include:
batteries
transistors
computer chips
energy generation
supercapacitors
DNA sequencing
water filters
antennas
touchscreens (for LCD or OLED displays)
solar cells
Spintronics-related products
Producing graphene
Graphene is indeed very exciting, but producing high quality materials is still a challenge. Dozens of companies around the world are producing different types and grades of graphene materials - ranging from high quality single-layer graphene synthesized using a CVD-based process to graphene flakes produced from graphite in large volumes.
High-end graphene sheets are mostly used in R&D activities or in extreme applications such as sensors, but graphene flakes, produced in large volumes and at lower prices, are adopted in many applications such as sports equipment, consumer electronics, automotive and more.
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