An all-in-one Ag₂Se-based flexible solar-thermoelectric generator with photothermal integration

Area of Science:

• Materials Science
• Energy Harvesting
• Nanotechnology

Background:

• Flexible solar-thermoelectric generators are crucial for wearable electronics.
• Simultaneous high photothermal and thermoelectric performance is challenging.

Purpose of the Study:

• To develop an integrated solar-thermoelectric generator with enhanced performance.
• To utilize silver selenide (Ag2Se) thin films as a light-absorbing terminal.

Main Methods:

• Fabrication of a multilayer architecture with Ag2Se thin films, an infrared-reflective layer, and an anti-reflective coating.
• Characterization of solar-selective absorption and photothermal conversion efficiency.
• Evaluation of the generator's temperature difference and power density.

Main Results:

• Achieved a photothermal conversion efficiency of 87.6% for Ag2Se.
• Demonstrated a maximum temperature difference of 19.6 K and power density of 0.17 μW cm⁻².
• Observed stable peak output power of ~1 μW under prolonged sunlight.

Conclusions:

• The proposed multilayer design is effective for high-efficiency solar-thermoelectric generators.
• This strategy broadens the application of narrow-bandgap thermoelectric films in photothermal energy conversion.