Deintercalation
Definition and meaning of Deintercalation in chemistry.
Deintercalation is the removal of guest ions, atoms, or molecules from the space between the layers of a host crystal structure, reversing the process of intercalation.
In more detail
Many solids, such as graphite, transition-metal dichalcogenides, and layered oxides, have weakly bonded sheets held apart by van der Waals forces, leaving galleries that can host smaller species. When those guest species diffuse out, the host layers typically contract and an atom within the lattice changes oxidation state to balance the charge lost with the departing ion. This reversible removal-and-reinsertion behavior underlies rechargeable battery electrodes, since repeated deintercalation and intercalation cycles store and release charge without destroying the host framework.
Key facts
| Reverse process | Intercalation |
|---|---|
| Example reaction | LiCoO2 → Li(1-x)CoO2 + xLi+ + xe− |
| Common host materials | Graphite, LiCoO2, TiS2, MoS2 |
| Field | Inorganic Chemistry |
During charging of a lithium-ion battery, Li+ ions are deintercalated from the layered LiCoO2 cathode, oxidizing Co3+ to Co4+, while the released Li+ migrates through the electrolyte and intercalates into the graphite anode.
Frequently asked questions
How does deintercalation differ from intercalation?
Intercalation is the insertion of guest species between the layers of a host lattice; deintercalation is the reverse step, in which those guest species leave. Together they form a reversible cycle in layered host materials.
Why is deintercalation important for batteries?
It is the mechanism by which lithium-ion battery cathodes release Li+ ions during charging, making it central to how rechargeable intercalation-type batteries store and deliver energy.