High-Performance Flexible Bismuth Telluride Thin Film from Solution Processed Colloidal Nanoplates

Area of Science:

• Materials Science
• Solid-State Physics
• Energy Conversion

Background:

• Thermoelectric generators offer eco-friendly solid-state energy conversion.
• Flexible thermoelectric generators are ideal for powering wearable electronics using ambient heat.
• Bismuth telluride materials perform optimally near room temperature, suiting body heat applications.

Purpose of the Study:

• To develop flexible bismuth telluride (Bi2Te3) thin films for thermoelectric generators.
• To utilize low-cost, scalable manufacturing methods for Bi2Te3 thin film deposition.
• To assess the thermoelectric performance and mechanical flexibility of the fabricated films.

Main Methods:

• Bi2Te3 thin films were synthesized and deposited on flexible polyimide substrates.
• Nanocrystal dimensions were characterized (35 ± 15 nm thickness, 692 ± 186 nm lateral).
• Aerosol jet printing was employed for fabricating thermoelectric thin films.

Main Results:

• The Bi2Te3 thin films achieved a peak power factor of 0.35 mW/m·K² at 433 K.
• The films maintained 77% of their initial electrical resistance after 1000 bending cycles (50mm ROC).
• High thermoelectric performance was demonstrated on flexible substrates using scalable methods.

Conclusions:

• Flexible Bi2Te3 thin films exhibit promising thermoelectric properties and mechanical robustness.
• Additive manufacturing techniques like aerosol jet printing are viable for creating flexible thermoelectric generators.
• These advancements support the development of efficient, body-heat-powered wearable devices.