Thermal Transport Properties of Two-Dimensional Materials

Two-dimensional materials exhibit unique thermal transport characteristics arising from their atomically thin structure and strong in-plane bonding. Within the layer, covalent bonds facilitate rapid phonon propagation and exceptionally high in-plane thermal conductivity, whereas weak interlayer van der Waals forces impede heat flow in the through-plane direction, often by orders of magnitude. This pronounced anisotropy can be further tuned by structural engineering, such as rotational misalignment or isotope enrichment, which selectively scatter phonons and modulate lattice vibrations. Beyond fundamental interest, controlling heat flow in these materials is crucial for next-generation electronics, flexible devices, thermoelectrics and thermal insulators. Advanced fabrication and characterisation techniques have enabled systematic studies of phonon dynamics, non-Fourier conduction regimes, and interface conductances, paving the way for bespoke heat management solutions across multiple scales.

Research from Nature Portfolio

Recent studies have demonstrated that surface phonon polaritons can mediate heat conduction over micrometre scales in polar dielectric nanoribbons, revealing non-Fourier behaviour and offering a new mechanism for directed heat transport beyond conventional phonon diffusion. Another investigation has shown that introducing random interlayer rotations in van der Waals thin films produces extremely anisotropic thermal conductors, with in-plane conductivities approaching single-crystal values while through-plane conductivities fall to glass-like levels. A further work has achieved record in-plane thermal conductivity in monolayer hexagonal boron nitride by controlling boron isotope concentration, illustrating the potential of isotope engineering to enhance heat dissipation in electrically insulating 2D films.

Thermal Transport Properties of Two-Dimensional Materials publication trend

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

Technical terms

Thermal conductivity: A material’s intrinsic ability to conduct heat, expressed in watts per metre-kelvin (W m⁻¹ K⁻¹).

Phonon polariton: A hybrid quasiparticle arising from coupling between photons and optical phonons at a dielectric surface, capable of supporting long-range heat transfer.

Anisotropy: The property of exhibiting different thermal conductivities along different crystallographic or structural directions.

Van der Waals heterostructure: A stack of atomically thin layers assembled via weak interlayer forces, enabling tailored electronic and thermal behaviours.

Phononic crystal: An engineered structure with periodic variations in density or elasticity designed to control phonon propagation and thermal transport.

References

1. Low-dimensional heat conduction in surface phonon polariton waveguide. Nature Communications (2023).
2. Extremely anisotropic van der Waals thermal conductors. Nature (2021).
3. Modulating the thermal conductivity in hexagonal boron nitride via controlled boron isotope concentration. Communications Physics (2019).
4. Tuning the Through-Plane Lattice Thermal Conductivity in van der Waals Structures through Rotational (Dis)ordering. ACS Nano (2023).
5. Lateral Heterostructure Formed by Highly Thermally Conductive Fluorinated Graphene for Efficient Device Thermal Management. Advanced Science (2024).
6. MoS2 phononic crystals for advanced thermal management. Science Advances (2024).