Tellurium as a high-performance elemental thermoelectric

Area of Science:

• Materials Science
• Solid State Physics
• Condensed Matter Physics

Background:

• High-efficiency thermoelectric materials necessitate high electrical conductivity.
• Degenerate band valleys provide numerous conduction channels, enhancing conductivity without negatively impacting other properties, thus improving thermoelectric performance.

Purpose of the Study:

• To demonstrate that inherent band nesting in semiconductors can achieve high thermoelectric performance.
• To showcase elemental tellurium as a high-performance thermoelectric material, filling a performance gap for elemental thermoelectrics between 300-700 K.

Main Methods:

• Investigated the thermoelectric properties of elemental tellurium.
• Utilized the concept of inherent band nesting to achieve a large number of effective band valley degeneracy.

Main Results:

• Elemental tellurium exhibited a high thermoelectric figure of merit of unity.
• This performance was achieved across a temperature range of 300-700 K.
• Demonstrated the effectiveness of band nesting for enhancing thermoelectric performance.

Conclusions:

• Elemental tellurium is a promising high-performance thermoelectric material.
• The strategy of utilizing inherent band nesting and band valley degeneracy is effective for improving thermoelectric materials.
• This concept is broadly applicable to other thermoelectrics with similar band structures.