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Low-temperature sintering of Ag nanoparticles for high-performance thermoelectric module design


To facilitate the development of thermoelectric modules for various operating temperature ranges, a connection technology that is suitable for heat-sensitive thermoelectric materials and capable of realizing both low-temperature connections and high-temperature service is required. Here we use low-temperature sintering of silver nanoparticles as an approach to connect the electrode and metallization layer of low- (Bi2Te3-based), medium- (PbTe-based) and high-temperature (half-Heusler-based) thermoelectric modules. Owing to the low melting point of Ag nanoparticles and the high stability in the sintered bulk, the processing temperature of the module is decoupled from the operating temperature, avoiding welding thermal stress. We demonstrate a conversion efficiency of ~11% at the temperature difference of 550 K for the PbTe-based module. Additionally, the module’s performance remains nearly unchanged throughout thermal cycling between hot-side temperatures of 593 and 793 K for 50 cycles. Our work accelerates the development of advanced modules for thermoelectric power generation.

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Fig. 1: Module welding temperature and thermoelectric conversion efficiency.
Fig. 2: Characterization of Ag NPs and corresponding sintered junctions.
Fig. 3: Characterization of the PbTe-based module connection layer.
Fig. 4: Performance of the PbTe-based module.

Data availability

All data generated or analysed during this study are included in the article, its Supplementary Information and the Source data provided with this paper.


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This work was supported by the Shenzhen Science and Technology Program (KQTD20200820113045081). Q.Z. acknowledges financial support from the National Natural Science Foundation of China (52172194 and 51971081), the Natural Science Foundation for Distinguished Young Scholars of Guangdong Province of China (2020B1515020023) and the Shenzhen Science and Technology Program (RCJC20210609103733073). J.M. acknowledges financial support from the National Natural Science Foundation of China (52101248), Shenzhen Fundamental Research Projects (JCYJ20210324132808020) and Shenzhen Stable Support Plan for Higher Education Institutions (GXWD20220818151757003).

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Authors and Affiliations



Q.Z., Z.R., J.M. and L.Y. designed this work. L.Y., X.W., J.C. and X.B. synthesized the samples and conducted the transport property measurements. F.Y. and Z.D. synthesized the Ag NP paste. L.Y. conducted the experimental study on sintered connection and characterization of the junctions. Y.W. and W.X. performed the TEM observations. L.Y. and X.B. conducted the experimental study on module fabrication and characterization. Q.Z., L.Y., Z.R., J.M., F.C., H.J., J.S., X.L. and M.L. discussed the results. L.Y., Q.Z., J.M. and Z.R. wrote this paper, and all authors edited it.

Corresponding authors

Correspondence to Jun Mao, Mingyu Li, Zhifeng Ren or Qian Zhang.

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Nature Energy thanks Johannes de Boor, Michihiro Ohta and Qingyu Yan for their contribution to the peer review of this work.

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Supplementary Figs. 1–33 and Tables 1–6.

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Yin, L., Yang, F., Bao, X. et al. Low-temperature sintering of Ag nanoparticles for high-performance thermoelectric module design. Nat Energy 8, 665–674 (2023).

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