Engineering Dual p-n-Type CuI with Significant Enhanced Performance for Advanced Thermoelectric Applications.

Area of Science:

• Materials Science
• Solid State Physics
• Energy Harvesting

Background:

• Copper iodide (CuI) is a known p-type thermoelectric material.
• Developing n-type CuI and integrating both types for thermoelectric generators (TEGs) is underexplored.

Purpose of the Study:

• To tune thermoelectric properties of CuI by incorporating silver (Ag).
• To synthesize both p-type and n-type CuI materials.
• To evaluate their potential for thermoelectric applications and building heat loss mitigation.

Main Methods:

• Successive Ionic Layer Adsorption and Reaction (SILAR) method for material synthesis.
• Incorporation of Ag into CuI to create AgₓCu₁₋ₓI.
• Characterization of thermoelectric properties (Seebeck coefficient, figure of merit ZT).

Main Results:

• Synthesized p-type Ag₀.₂Cu₀.₈I with ZT of 0.47 at 340 K and a Seebeck coefficient of 810 μV·K⁻¹.
• Achieved n-type Ag₀.₉Cu₀.₁I with an exceptional ZT of 2.5 at 340 K and an ultrahigh Seebeck coefficient of -1891 μV·K⁻¹.
• Demonstrated a prototype thermoelectric glazing unit (5 × 5 cm²) with a 14 K temperature differential.

Conclusions:

• Ag-doped CuI offers a cost-effective, scalable, and greener alternative to conventional thermoelectric materials like Bi₂Te₃ and PbTe.
• The synthesized n-type CuI exhibits superior thermoelectric performance.
• CuI-based materials show promise for dual applications in power generation and building thermal management.