Intercalation Chemistry of Two-Dimensional Materials

Intercalation chemistry exploits the van der Waals gaps in layered two-dimensional (2D) materials to insert guest species—atoms, ions or molecules—between host sheets. This process enables precise control over electronic, optical and mechanical properties by modulating interlayer spacing, inducing charge transfer and triggering phase transitions. In graphene, transition metal dichalcogenides and other 2D hosts, intercalation has been used to tune conductivity, induce superconductivity, adjust thermal transport and create novel heterostructures. By selecting specific intercalants and host lattices, researchers can engineer band structures, tailor ion-transport pathways and stabilise unconventional electronic phases. The ability to reversibly intercalate species under mild conditions also opens routes to scalable production of single-layer nanosheets, low-temperature synthesis of hybrid materials and dynamic control of functional properties for energy storage, nanoelectronics and sensing applications.

Research from Nature Portfolio

Recent work has visualised the atomic arrangement of alkali metals intercalated in bilayer graphene, revealing that potassium, rubidium and cesium form bilayer hcp stacks with a characteristic C6M2C6 motif. Advanced transmission electron microscopy combined with spectroscopic techniques quantified a substantial negative charge transfer to the graphene, confirming enhanced electronic doping and suggesting routes to increase intercalation capacity by controlling host thickness. In twisted bilayer MoS2, investigators have stabilised an intermediate lightly intercalated state across entire flakes by promoting top-surface lithium insertion. Spectroscopic mapping showed Raman peak splitting arising from symmetry breaking in the H phase, offering new insight into non-uniform intercalation dynamics and highlighting the potential of Moiré engineering to modulate guest-host interactions during battery cycling.

Intercalation Chemistry of Two-Dimensional Materials publication trend

The graph below shows the total number of articles in intercalation chemistry of two-dimensional materials across all publications each year (not limited to Nature Index journals).

Technical terms

Intercalation: Insertion of guest atoms, ions or molecules into the interlayer spaces of layered materials.

Two-dimensional materials: Crystalline solids consisting of single or few atomic layers with strong in-plane bonds and weak out-of-plane interactions.

Van der Waals gap: The space between adjacent layers in a 2D material held together by weak dispersion forces.

Charge transfer: Movement of electronic charge between intercalant and host layers, altering electrical properties.

References

1. Alkali metal bilayer intercalation in graphene. Nature Communications (2024).
2. Tandem intercalation strategy for single-layer nanosheets as an effective alternative to conventional exfoliation processes. Nature Communications (2015).
3. Intercalation as a versatile tool for fabrication, property tuning, and phase transitions in 2D materials. npj 2D Materials and Applications (2021).
4. Enhancing Light–Matter Interactions in MoS2 by Copper Intercalation. Advanced Materials (2021).
5. Observation of an intermediate state during lithium intercalation of twisted bilayer MoS2. Nature Communications (2022).