Boron-Doped Single-Walled Carbon Nanotubes with Enhanced Thermoelectric Power Factor for Flexible Thermoelectric Devices
ACS Appl. Ener. Mat. 3, 3 (2020).
Y. Liu, V. Khavrus, T. Lehmann, H. L. Yang, L. Stepien, M. Greifzu, S. Oswald, T. Gemming, V. Bezugly, and G. Cuniberti.
Journal DOI: https://doi.org/10.1021/acsaem.9b02243

We report a detailed experimental and theoretical study on thermoelectric properties of boron-doped single-walled carbon nanotubes (B-SWCNTs), which are versatile building blocks of flexible thermoelectric devices. Implantations of substitutional boron dopants (0.1-0.5 atom %) in SWCNTs are realized using thermal diffusion. The after-synthesis boron doping simultaneously improves the Seebeck coefficient (S) and electrical conductivity (σ) of SWCNT networks, leading to an S2σ value of 226 μW/mK2. First-principle calculations indicate that a few tenths atom % of substitutional boron atoms improve the S value of semi-conducting SWCNTs but reduce the electron conductance in individual SWCNTs. The high σ of B-SWCNT networks is attributed to the improved electrical transport between laterally contacted metallic and semi-conducting nanotubes. The produced B-SWCNTs are stable over high-temperature annealing or processing in liquid media, which inspired us to fabricate thermoelectric modules by a low-cost printing method. The modules demonstrate an increased thermoelectric efficiency by 76% compared to those with undoped SWCNTs. This work provides a feasible fabrication strategy and physical insights for B-SWCNT-based flexible thermoelectrics.

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©10.1021/acsaem.9b02243
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Boron-Doped Single-Walled Carbon Nanotubes with Enhanced Thermoelectric Power Factor for Flexible Thermoelectric Devices
ACS Appl. Ener. Mat. 3, 3 (2020).
Y. Liu, V. Khavrus, T. Lehmann, H. L. Yang, L. Stepien, M. Greifzu, S. Oswald, T. Gemming, V. Bezugly, and G. Cuniberti.
Journal DOI: https://doi.org/10.1021/acsaem.9b02243

We report a detailed experimental and theoretical study on thermoelectric properties of boron-doped single-walled carbon nanotubes (B-SWCNTs), which are versatile building blocks of flexible thermoelectric devices. Implantations of substitutional boron dopants (0.1-0.5 atom %) in SWCNTs are realized using thermal diffusion. The after-synthesis boron doping simultaneously improves the Seebeck coefficient (S) and electrical conductivity (σ) of SWCNT networks, leading to an S2σ value of 226 μW/mK2. First-principle calculations indicate that a few tenths atom % of substitutional boron atoms improve the S value of semi-conducting SWCNTs but reduce the electron conductance in individual SWCNTs. The high σ of B-SWCNT networks is attributed to the improved electrical transport between laterally contacted metallic and semi-conducting nanotubes. The produced B-SWCNTs are stable over high-temperature annealing or processing in liquid media, which inspired us to fabricate thermoelectric modules by a low-cost printing method. The modules demonstrate an increased thermoelectric efficiency by 76% compared to those with undoped SWCNTs. This work provides a feasible fabrication strategy and physical insights for B-SWCNT-based flexible thermoelectrics.

Cover
©10.1021/acsaem.9b02243
Share


Involved Scientists