Thermal Transport Phenomena in Nanostructured Materials

Thermal transport in nanostructured materials is governed by interactions of quantised lattice vibrations (phonons) with boundaries, interfaces and defects, leading to departures from classical macroscopic behaviour. At length scales comparable to the phonon mean free path, heat conduction may transition from diffusive to ballistic regimes, and interfaces introduce additional thermal resistance that can be engineered for enhanced control. Nanostructuring in one, two and three dimensions enables modulation of phonon spectra, the induction of coherent or incoherent transport, and the emergence of phenomena such as thermal rectification and anisotropic conductance. These effects underpin advances in thermal management for microelectronics, the design of high-efficiency thermoelectric generators and the development of phononic devices capable of active heat-flow control.

Research from Nature Portfolio

Recent studies demonstrate that cross-shaped heterostructures of graphene and hexagonal boron nitride can be tailored to tune thermoelectric performance by adjusting arm widths, offering a route to enhance the figure of merit through the interplay of electronic conductance and phononic thermal conductance. Investigations of carbon nanotube bundles reveal that matching the curvature of core and outer nanotubes reduces phonon scattering at van der Waals interfaces, leading to improved anisotropic thermal conductance. These findings highlight the potential of interface engineering and geometric design in van der Waals heterostructures for precise control of heat transport at the nanoscale.

Thermal Transport Phenomena in Nanostructured Materials publication trend

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

Technical terms

Phonon: A quantised mode of lattice vibration that carries heat energy in crystalline solids.

Thermal conductivity: A measure of a material’s ability to conduct heat, arising from phonon or electron transport.

Ballistic transport: Heat conduction regime in which phonons travel without scattering over distances comparable to sample dimensions.

Diffusive transport: Conventional heat conduction regime where frequent phonon scattering leads to a steady-state temperature gradient described by Fourier’s law.

Thermal rectification: Asymmetric heat flow behaviour in which heat current differs significantly depending on the direction of the temperature gradient.

Interface thermal resistance: Additional resistance to heat flow arising at the boundary between two dissimilar materials, also known as Kapitza resistance.

References

1. Flexible thermoelectrics in crossed graphene/hBN composites. Scientific Reports (2024).
2. Curvature and van der Waals interface effects on thermal transport in carbon nanotube bundles. Scientific Reports (2022).
3. Mechanical and Lattice Thermal Properties of Si-Ge Lateral Heterostructures. Molecules (2024).
4. Room temperature thermal rectification in suspended asymmetric graphene ribbon. Nanotechnology (2024).
5. Graphene and 2D Hexagonal Boron Nitride Heterostructure for Thermal Management in Actively Tunable Manner. Nanomaterials (2022).