Does Graphite Conduct Electricity: 13 Facts You Should Know

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Graphite is an allotropic form of carbon consisting of sacks of carbon layers. Let us know about conducting nature of graphite.

Graphite is a good conductor of electricity even though bulk carbon does not contribute to the conduction. At the nanoscale, the orientation of carbon atoms in the graphite lattice faces different directions, so electrical conduction is possible in graphite.

Graphite is a crystalline solid with a well-defined unit cell, which is a major contribution to electrical conduction. Let us concentrate on the facts involved in electrical conduction in graphite.

Can graphite be used as the electrical conductor?

Graphite is widely used as a dry lubricant. Let us focus on how graphite is used as an electrical conductor.

Graphite is the most stable isotope of carbon used only in short-distance electrical conduction, such as brushes in DC motors. It cannot be implemented as an electrical conductor in long wires due to tensile strength and flexibility.

Graphite is mechanically weak, is not so flexible, and does not have a tensile property. Graphite is highly resistive than copper, so it is mostly used in resistors and rheostats.

How is graphite an electrical conductor?

Material is said to be electrically conductive if there is dislodge of electrons in the outer shell. Let us provide the process of electrical conductivity in graphite.

The bond structure of the carbon atoms in graphite is like layers in which each carbon atom shares a bond with three other atoms leaving one spare valence electron. The spare electron is free to move around the lattice carrying charges. In this way, graphite acts as an electrical conductor.

The graphite consists of carbon atom layers, the extra electron per carbon can generate a sea of delocalized electrons available for conduction.

Why does graphite conduct electricity?

The electric conductivity of the material defines its quantified measurement of available charges. Let us demonstrate the reason for electrical conductivity in graphite.

Graphite conducts electricity because it consists of loosely bounded pi-electrons with a weak Vander Waals interaction at each layer. Thus these pi electrons are easily set free for motion and carry numerous amount of charges along the lattice structure to conduct electricity.

The flow of delocalized electrons from each layer carries the charges. It makes a way free from other traffic for the conduction because of weak Vander Waals force between the layers.

When does graphite conduct electricity?

Material can conduct electricity when an electron per atom is set free. Let us know the scenario of electrical conduction in graphite.

When graphene layers are collectively sacked together to form solid graphite, a sea of free electrons is generated. Under these circumstances, graphite can conduct electricity.

What is the electric conductivity of graphite?

An electric conductor is any material capable of allowing the electric current to pass through them. Let us demonstrate the electric conductivity of graphite.

The electrical conductivity of graphite is approximately estimated at around 104 Scm-1. The electrical conductivity in graphite always takes place perpendicular to the carbon layers.

Is graphite a good electric conductor?

A material is called a good conductor when it has a maximum tendency to create a free electron after bonding. Let’s find out how graphite can be a good conductor.

Graphite is a good electric conductor. The tendency to create a mobile electron per each carbon atom makes graphite a good conductor. These mobile electrons wander around the lattice carrying charges creating a hole leading to good electric conduction in graphite.

Structure and bonding of graphite

Graphite is a multi-layered brittle solid, and each layer is known as graphene. Let us depict the bonding structure of graphite.

  • Structure of Graphite –Carbon atoms are aligned in honeycomb manner. Each carbon atom is sp3 hybridized having trigonal planar geometry.
  • Bonding of Graphite –Each carbon atom held together by strong covalent bond. The bond length between each atom is 0.142nm, and the interplanar distance is 0.335nm.
Graphene graphite relation
Structure of graphite
Image credits: Wikimedia commons

There are two forms of graphite arrangement based on stacking graphene layers in the lattice called alpha and beta graphite. The sequence of arrangement of alpha graphite in the layer is ABAB, while the sequence of arrangement of beta graphite is ABCABC.

Properties of graphite

Graphite is solid having physical and chemical properties. Let us understand some of the properties of graphite.

  • Graphite is crystalline in nature soft and soapy to touch.
  • Graphite is opaque, grayish-black substance.
  • Graphite is smooth, slippery and lighter than the diamond.
  • Graphite can conduct heat and electricity.
  • Graphite is non-toxic and non-inflammable.
  • Graphite has high melting and boiling point.

Uses of graphite as an electrical conductor

Graphite has high heat endurance so it is used as an electric conductor. Let us list out some of the uses of graphite as an electrical conductor.

  • Portable electronic devices consist of batteries made using graphite. Portable CD players, laptops, mobiles, tablets even the battery of electric vehicles use graphite.
  • Graphite is used as an electrode in an electrochemical cell.
  • Graphite is also used in electric brushes and electric paints.

Does graphite conduct heat?

Conduction of heat in any material is similar to electrical conduction. Let us understand the thermal conductivity of graphite.

Graphite is a good conductor of heat. It conducts heat due to weak vender Waals interaction between the graphene layers. Since graphite consists of one free electron at the outermost shell of the carbon caused due to delocalized bonding in the layer leading to thermal conductivity.

Why does graphite have a high melting point?

The value of the melting point of several materials depends on the existence of Vander Waals force. Let us discuss the melting point of graphite.

The hexagonal structure holds the graphite layers by Vander Waals force in between the parallel layers, and the covalent bond between the molecules becomes stronger, which requires a large amount of energy to break the interaction. So graphite has a high melting point to break the bond.

Why does a diamond not conduct electricity?

Diamond is also an allotrope of carbon different from graphite because of the lattice arrangement of carbon. Let us focus on the electric conductivity of diamonds.

Diamond is a poor conductor of electricity because it consists of carbon of four valence electrons in which each electron is involved in bonding with the other neighbor atom, and no spare electron is left free to move around the lattice to carry the charges.

Another reason for the diamond to exhibit poor electrical conductivity is the absence of Vander Waals force between the layers of the diamond.

Conclusion

Let us wrap up this post by concluding that graphite is a very good conductor of electricity due to its crystalline structure with limited application in a piece of real-world electrical equipment.

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