Next Article in Journal
Detection of C-Reactive Protein Using Histag-HRP Functionalized Nanoconjugate with Signal Amplified Immunoassay
Next Article in Special Issue
Properties of Graphene-Related Materials Controlling the Thermal Conductivity of Their Polymer Nanocomposites
Previous Article in Journal
Therapeutic Delivery of rAAV sox9 via Polymeric Micelles Counteracts the Effects of Osteoarthritis-Associated Inflammatory Cytokines in Human Articular Chondrocytes
Previous Article in Special Issue
Enhancement of Thermal Boundary Conductance of Metal–Polymer System
Article

Phonon Bridge Effect in Superlattices of Thermoelectric TiNiSn/HfNiSn With Controlled Interface Intermixing

1
Institute of Physics, Johannes Gutenberg University, Staudingerweg 7, 55128 Mainz, Germany
2
Graduate School of Excellence Materials Science in Mainz, Staudingerweg 9, 55128 Mainz, Germany
3
Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, 08193 Barcelona, Spain
4
Institute of Applied Geosciences, Darmstadt University of Technology, Schnittspahnstrasse 9, 64287 Darmstadt, Germany
*
Author to whom correspondence should be addressed.
Nanomaterials 2020, 10(6), 1239; https://doi.org/10.3390/nano10061239
Received: 5 June 2020 / Revised: 21 June 2020 / Accepted: 22 June 2020 / Published: 25 June 2020
(This article belongs to the Special Issue Thermal Transport in Nanostructures and Nanomaterials)
The implementation of thermal barriers in thermoelectric materials improves their power conversion rates effectively. For this purpose, material boundaries are utilized and manipulated to affect phonon transmissivity. Specifically, interface intermixing and topography represents a useful but complex parameter for thermal transport modification. This study investigates epitaxial thin film multilayers, so called superlattices (SL), of TiNiSn/HfNiSn, both with pristine and purposefully deteriorated interfaces. High-resolution transmission electron microscopy and X-ray diffractometry are used to characterize their structural properties in detail. A differential 3 ω -method probes their thermal resistivity. The thermal resistivity reaches a maximum for an intermediate interface quality and decreases again for higher boundary layer intermixing. For boundaries with the lowest interface quality, the interface thermal resistance is reduced by 23% compared to a pristine SL. While an uptake of diffuse scattering likely explains the initial deterioration of thermal transport, we propose a phonon bridge interpretation for the lowered thermal resistivity of the interfaces beyond a critical intermixing. In this picture, the locally reduced acoustic contrast of the less defined boundary acts as a mediator that promotes phonon transition. View Full-Text
Keywords: interface; thermal conductivity; superlattice; intermixing; coherent phonon; roughness; 3 omega; 3 omega method; magnetron sputtering; half-Heusler; thermoelectric; thin film; TiNiSn; HfNiSn; thermal boundary resistance interface; thermal conductivity; superlattice; intermixing; coherent phonon; roughness; 3 omega; 3 omega method; magnetron sputtering; half-Heusler; thermoelectric; thin film; TiNiSn; HfNiSn; thermal boundary resistance
Show Figures

Figure 1

MDPI and ACS Style

Heinz, S.; Angel, E.C.; Trapp, M.; Kleebe, H.-J.; Jakob, G. Phonon Bridge Effect in Superlattices of Thermoelectric TiNiSn/HfNiSn With Controlled Interface Intermixing. Nanomaterials 2020, 10, 1239. https://doi.org/10.3390/nano10061239

AMA Style

Heinz S, Angel EC, Trapp M, Kleebe H-J, Jakob G. Phonon Bridge Effect in Superlattices of Thermoelectric TiNiSn/HfNiSn With Controlled Interface Intermixing. Nanomaterials. 2020; 10(6):1239. https://doi.org/10.3390/nano10061239

Chicago/Turabian Style

Heinz, Sven, Emigdio C. Angel, Maximilian Trapp, Hans-Joachim Kleebe, and Gerhard Jakob. 2020. "Phonon Bridge Effect in Superlattices of Thermoelectric TiNiSn/HfNiSn With Controlled Interface Intermixing" Nanomaterials 10, no. 6: 1239. https://doi.org/10.3390/nano10061239

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop