Thermoelectric materials can convert waste heat directly into electricity. However, their practical application is often limited by the long-term stability of high-performance materials. A recent study involving researchers from IFW Dresden addresses this challenge.
The research team succeeded in controlling the movement of zinc ions within the thermoelectric material β-Zn₄Sb₃—an important step toward significantly slowing down its degradation. This is achieved by applying a zinc oxide coating only a few nanometres thick using Atomic Layer Deposition (ALD). Rather than merely protecting the surface, the coating actively influences atomic-scale processes inside the material: it regulates the migration of zinc ions while simultaneously modifying the propagation of heat-carrying lattice vibrations (phonons). As a result, the material retains its excellent thermoelectric performance while its structural stability is significantly improved.
Another important finding: The coated samples remained structurally stable even after more than 39,000 thermal cycles under a temperature gradient. The study thus demonstrates a new way to significantly extend the lifetime of thermoelectric materials and further advance their use for waste heat recovery.
The study also highlights a new role for Atomic Layer Deposition. Beyond protecting surfaces and improving material properties, ALD enables the targeted control of atomic-scale processes within a material. This approach opens up new opportunities for the development of durable thermoelectric materials and future energy applications.
The work also brings together two of IFW Dresden's research strengths: the development of high-performance thermoelectric materials and atomic-scale surface engineering using Atomic Layer Deposition (ALD).
Original publication
Amin Bahrami et al.: Atomic-scale regulation of ion motion and phonon scattering in β-Zn₄Sb₃ thermoelectrics by atomic layer deposition, Science Advances (2026)
https://www.science.org/doi/full/10.1126/sciadv.aeg3850
Contact
Dr.-Ing. Amin Bahrami
Surface-Functionalized Materials
E-mail: a.bahrami@ifw-dresden.de
Patricia Bäuchler
Communication
E-mail: p.baeuchler@ifw-dresden.de
