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Abstract Thermoelectric generators are an environmentally friendly and reliable solid‐state energy conversion technology. Flexible and low‐cost thermoelectric generators are especially suited to power flexible electronics and sensors using body heat or other ambient heat sources. Bismuth telluride (Bi2Te3) based thermoelectric materials exhibit their best performance near room temperature making them an ideal candidate to power wearable electronics and sensors using body heat. In this report, Bi2Te3thin films are deposited on a flexible polyimide substrate using low‐cost and scalable manufacturing methods. The synthesized Bi2Te3nanocrystals have a thickness of 35 ± 15 nm and a lateral dimension of 692 ± 186 nm. Thin films fabricated from these nanocrystals exhibit a peak power factor of 0.35 mW m−1·K−2at 433 K, which is among the highest reported values for flexible thermoelectric films. In order to evaluate the flexibility of the thin films, static and dynamic bending tests are performed while monitoring the change in electrical resistivity. After 1000 bending cycles over a 50 mm radius of curvature, the change in electrical resistance of the film is 23%. Using Bi2Te3solutions, the ability to print thermoelectric thin films with an aerosol jet printer is demonstrated, highlighting the potential of additive manufacturing techniques for fabricating flexible thermoelectric generators.
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Si0.97Ge0.03 microelectronic thermoelectric generators with high power and voltage densities
Abstract Microelectronic thermoelectric generators are one potential solution to energizing energy autonomous electronics, such as internet-of-things sensors, that must carry their own power source. However, thermoelectric generators with the mm2footprint area necessary for on-chip integration made from high thermoelectric figure-of-merit materials have been unable to produce the voltage and power levels required to run Si electronics using common temperature differences. We present microelectronic thermoelectric generators using Si0.97Ge0.03, made by standard Si processing, with high voltage and power generation densities that are comparable to or better than generators using high figure-of-merit materials. These Si-based thermoelectric generators have <1 mm2areas and can energize off-the-shelf sensor integrated circuits using temperature differences ≤25 K near room temperature. These generators can be directly integrated with Si circuits and scaled up in area to generate voltages and powers competitive with existing thermoelectric technologies, but in what should be a far more cost-effective manner.
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- Award ID(s):
- 1707581
- PAR ID:
- 10188674
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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