Giant Thermoelectric Power Factor Anisotropy in PtSb_1.4Sn_0.6

Area of Science:

• Materials Science
• Solid State Physics
• Thermoelectrics

Background:

• Thermoelectric materials convert heat to electricity and vice versa.
• Anisotropy in thermoelectric properties can significantly impact device performance.
• Understanding new material phases is crucial for advancing thermoelectric applications.

Purpose of the Study:

• To synthesize and characterize a new platinum-antimony-tin (PtSbSn) phase with a marcasite structure.
• To investigate the anisotropic thermoelectric properties of the PtSbSn single crystal.
• To determine the origin of the observed anisotropy in the thermoelectric power factor.

Main Methods:

• Single crystal synthesis using ambient pressure flux growth.
• Structural characterization to identify the new PtSbSn phase.
• Measurement of thermoelectric properties, including Seebeck coefficient and electrical conductivity, along principal crystallographic directions.

Main Results:

• A new PtSbSn phase with marcasite structure (orthorhombic unit cell) was successfully synthesized.
• Giant anisotropy was observed in the thermoelectric power factor (S²σ) of the PtSbSn single crystal.
• The anisotropy in S²σ is primarily attributed to large variations in the Seebeck coefficient along different directions.

Conclusions:

• The newly discovered PtSbSn phase exhibits significant directional dependence in its thermoelectric performance.
• Anisotropic Seebeck coefficients are the main drivers of the observed giant anisotropy in the power factor.
• This material shows potential for applications where directional thermoelectric effects are desired.