Performance boost for bismuth telluride thermoelectric generator via barrier layer based on low Young's modulus and particle sliding.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38057306.
- Also identified by DOI 10.1038/s41467-023-43879-8 and PMC identifier 10700503.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The lack of desirable diffusion barrier layers currently prohibits the long-term stable service of bismuth telluride thermoelectric devices in low-grade waste heat recovery. Here we propose a new design principle of barrier layers beyond the thermal expansion matching criterion. A titanium barrier layer with loose structure is optimized, in which the low Young's modulus and particle sliding synergistically alleviates interfacial stress, while the TiTe<sub>2</sub> reactant enables metallurgical bonding and ohmic contact between the barrier layer and the thermoelectric material, leading to a desirable interface characterized by high-thermostability, high-strength, and low-resistivity. Highly competitive conversion efficiency of 6.2% and power density of 0.51 W cm<sup>-2</sup> are achieved for a module with leg length of 2 mm at the hot-side temperature of 523 K, and no degradation is observed following operation for 360 h, a record for stable service at this temperature, paving the way for its application in low-grade waste heat recovery.