Parallel Dislocation Networks and Cottrell Atmospheres Reduce Thermal Conductivity of PbTe Thermoelectrics
Advanced Functional Materials, vol. 31
Abstract
Abstract Dislocations play an important role in thermal transport by scattering phonons. Nevertheless, for materials with intrinsically low thermal conductivity, such as thermoelectrics, classical models require exceedingly high numbers of dislocations (>10 12 cm –2 ) to further impede thermal transport. In this work, a significant reduction in thermal conductivity of Na 0.025 Eu 0.03 Pb 0.945 Te is demonstrated at a moderate dislocation density of 1 × 10 10 cm –2 . Further characteristics of dislocations, including their arrangement, orientation, and local chemistry are shown to be crucial to their phonon‐scattering effect and are characterized by correlative microscopy techniques. Electron channeling contrast imaging reveals a uniform distribution of dislocations within individual grains, with parallel lines along four <111> directions. Transmission electron microscopy (TEM) shows the parallel networks are edge‐type and share the same Burgers vectors within each group. Atom probe tomography reveals the enrichment of dopant Na at dislocation cores, forming Cottrell atmospheres. The dislocation network is demonstrated to be stable during in situ heating in the TEM. Using the Callaway transport model, it is demonstrated that both parallel arrangement of dislocations and Cottrell atmospheres make dislocations more efficient in phonon scattering. These two mechanisms provide new avenues to lower the thermal conductivity in materials for thermal‐insulating applications.
Authors 13
-
Max-Planck-Institut für Nachhaltige Materialien
Affiliation as printed
Max‐Planck‐Institut für Eisenforschung GmbH Max‐Planck‐Straße 1 40237 Düsseldorf Germany
-
Affiliation as printed
Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education School of Materials Science and Engineering Tongji University 4800 Caoan Road Shanghai 201804 China
Key Laboratory of Advanced Civil Engineering, Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800 Caoan Road, Shanghai, 201804 China
-
Affiliation as printed
Institute of Physics IA RWTH Aachen University 52056 Aachen Germany
Institute of Physics IA, RWTH Aachen University, 52056 Aachen, Germany
-
Max-Planck-Institut für Nachhaltige Materialien
Affiliation as printed
Max‐Planck‐Institut für Eisenforschung GmbH Max‐Planck‐Straße 1 40237 Düsseldorf Germany
-
Affiliation as printed
Department of Materials Science and Engineering Northwestern University Evanston 60208 USA
Department of Materials Science and Engineering, Northwestern University, Evanston, 60208 USA
-
Max-Planck-Institut für Nachhaltige Materialien
Affiliation as printed
Max‐Planck‐Institut für Eisenforschung GmbH Max‐Planck‐Straße 1 40237 Düsseldorf Germany
-
Max-Planck-Institut für Nachhaltige Materialien
Affiliation as printed
Max‐Planck‐Institut für Eisenforschung GmbH Max‐Planck‐Straße 1 40237 Düsseldorf Germany
-
Affiliation as printed
Institute of Physics IA RWTH Aachen University 52056 Aachen Germany
Institute of Physics IA, RWTH Aachen University, 52056 Aachen, Germany
-
Affiliation as printed
Department of Materials Science and Engineering Northwestern University Evanston 60208 USA
Department of Materials Science and Engineering, Northwestern University, Evanston, 60208 USA
-
Max-Planck-Institut für Nachhaltige Materialien
Affiliation as printed
Max‐Planck‐Institut für Eisenforschung GmbH Max‐Planck‐Straße 1 40237 Düsseldorf Germany
-
Affiliation as printed
Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education School of Materials Science and Engineering Tongji University 4800 Caoan Road Shanghai 201804 China
Key Laboratory of Advanced Civil Engineering, Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, 4800 Caoan Road, Shanghai, 201804 China
-
Christina Scheu corresponding
Max-Planck-Institut für Nachhaltige Materialien
Affiliation as printed
Max‐Planck‐Institut für Eisenforschung GmbH Max‐Planck‐Straße 1 40237 Düsseldorf Germany
-
Siyuan Zhang corresponding
Max-Planck-Institut für Nachhaltige Materialien
Affiliation as printed
Max‐Planck‐Institut für Eisenforschung GmbH Max‐Planck‐Straße 1 40237 Düsseldorf Germany
Cited by 82 stored of 82
No patents citing this paper on Lens.org (checked 2026-10-06).