How does graphite conduct electricity?

The structure of graphite is very unlike any other substances. It is composed of sheets of carbon atoms, and each of these is bonded to only three other atoms. This leaves the fourth valence electron of the carbon atom delocalized, which means it is free to move between the different sheets, therefore carrying the electrical charge through the network of carbon atoms which makes up the structure of graphite.

For any substance to be able to conduct electricity, first it must contain freely moving charged particles. These particles can either be electrons or ions, and they’re responsible for carrying the electric charge through any substance. With graphite and metal, electrical conduction is made possible by electrons which have been delocalized, which means they’re not firmly bound to any specific atom. Since these electrons are not bound, they’re free to roam, which is how the electrical current gets carried through most materials.

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