Graphite can conduct electricity because of its unique molecular structure. It is composed of carbon atoms arranged in layers of hexagonal lattices, where each carbon atom is bonded to three others. This leaves one electron per carbon atom free or "delocalized," meaning it is not involved in bonding and can move freely within the layers. These free electrons act as charge carriers, allowing electric current to flow easily through the graphite layers. The layers themselves are held together by weak forces, enabling electrons to move readily within each layer but not as easily between layers. This electron mobility gives graphite its ability to conduct electricity, similar to metals with their free electrons. The electrical conductivity is anisotropic, being much higher along the layers than perpendicular to them.

Key Points Behind Graphite’s Conductivity

• Carbon atoms form hexagonal layers bonded with three covalent bonds each.
• The fourth valence electron per carbon atom is free (delocalized).
• Delocalized electrons move freely within the layers, carrying electric charge.
• Layers weakly bonded allow easy movement of electrons within but less between layers.
• Graphite’s conductivity is similar in principle to metals, with free electrons acting as carriers.
• Conductivity depends on purity, temperature, and crystal orientation.