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Large Spin-Dependent Thermoelectric Effects in NiFe-based Interconnected Nanowire Networks
Nicolas Marchal1, Tristan da Câmara Santa Clara Gomes1, Flavio Abreu Araujo1
1Institute of Condensed Matter and Nanosciences, Université catholique de Louvain, Place Croix du Sud 1, Louvain-la-Neuve, 1348, Belgium.
Nanoscale Research Letters
|July 1, 2020
Summary
Nickel-iron (NiFe) alloy and NiFe/copper multilayered nanowire networks show significant thermoelectric properties. Giant magneto-thermopower effects up to 60% were observed, demonstrating magnetic control for flexible thermoelectric devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Thermoelectric materials convert heat to electricity.
- Nanostructured materials offer unique electronic and thermal properties.
- Magnetic control of thermoelectricity is an emerging field.
Purpose of the Study:
- To synthesize NiFe alloy and NiFe/Cu multilayered nanowire (NW) networks.
- To investigate the thermoelectric properties of these NW networks.
- To demonstrate giant magneto-thermopower (MTP) effects and their potential applications.
Main Methods:
- Template-assisted electrochemical synthesis of NW networks.
- Characterization of thermoelectric properties, including thermopower and Seebeck coefficient.
- Measurement of MTP effects in multilayered NWs.
Main Results:
- NiFe alloy NW networks exhibit large thermopower.
- NiFe/Cu multilayered NWs show giant MTP effects (25% at 300 K, 60% at 100 K).
- A large spin-dependent Seebeck coefficient of -12.3 μV/K was obtained at room temperature.
Conclusions:
- NiFe/Cu multilayered NW networks demonstrate significant MTP effects.
- Magnetic control of thermoelectric properties in flexible devices is feasible.
- These findings open avenues for advanced thermoelectric applications.
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