Unveiling Brass-Doped CoSb₃-Based Thermoelectric Materials Using Solid-State Reaction

Area of Science:

• Materials Science
• Solid State Physics
• Thermoelectrics

Background:

• Skutterudite (CoSb₃)-based materials are promising for mid-temperature thermoelectric applications.
• Their performance is linked to electrical properties and alloy design.

Purpose of the Study:

• To synthesize and characterize Brass_x/Co₄Sb_11.5Te_0.5 composites.
• To investigate the effects of co-doping with brass and tellurium on thermoelectric properties.

Main Methods:

• High-temperature solid-state reactions were used for synthesis.
• X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS) were employed for analysis.

Main Results:

• The primary crystal structure observed was CoSb₃, with minor impurity phases.
• Co-doping effectively regulated carrier concentration and enhanced the power factor.
• Nanostructures, grain boundaries, and defects reduced lattice thermal conductivity.

Conclusions:

• Brass_0.1/Co₄Sb_11.5Te_0.5 achieved a peak thermoelectric figure of merit (ZT) of 0.81 at 781 K.
• The study demonstrates a viable strategy for optimizing skutterudite thermoelectric materials.