Sandwich Engineering Advances Ductile Thermoelectrics.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Energy Harvesting

Background:

• Flexible thermoelectrics can power wearable electronics using body heat.
• Ductile semiconductors are ideal but balancing ductility and performance is difficult, especially for n-type materials.

Purpose of the Study:

• To design a novel n-type ductile thermoelectric material with enhanced performance and flexibility.
• To overcome the challenge of balancing ductility and thermoelectric efficiency in n-type semiconductors.

Main Methods:

• Fabrication of a sandwich-like thermoelectric film with Ag2(S, Se) core and Ag2Se shell layers.
• Characterization of structural, electrical, and thermal transport properties.
• Fabrication and testing of a flexible in-plane thermoelectric device.

Main Results:

• Achieved a record figure-of-merit of 0.91 at 323 K for n-type ductile semiconductors.
• Demonstrated excellent flexibility and a power density of 26.5 W m-2 at a 50 K temperature difference.
• The novel sandwich architecture significantly improved thermoelectric performance while maintaining ductility.

Conclusions:

• The developed Ag2(S, Se)-Ag2Se sandwich film offers a promising solution for high-performance flexible thermoelectrics.
• This material design strategy can pave the way for advanced self-powered wearable electronics.
• The study alleviates the long-standing compromise between thermoelectric performance and material ductility.