Carbon Nanotube-Polyurethane Composite Sheets for Flexible Thermoelectric Materials

Antonio J Paleo; Yadienka Martinez-Rubi; Beate Krause; Petra Pötschke; Michael B Jakubinek; Behnam Ashrafi; Christopher Kingston

doi:10.1021/acsanm.3c03247

Carbon Nanotube-Polyurethane Composite Sheets for Flexible Thermoelectric Materials

ACS Appl Nano Mater. 2023 Sep 19;6(19):17986-17995. doi: 10.1021/acsanm.3c03247. eCollection 2023 Oct 13.

Authors

Antonio J Paleo¹, Yadienka Martinez-Rubi², Beate Krause³, Petra Pötschke³, Michael B Jakubinek², Behnam Ashrafi⁴, Christopher Kingston²

Affiliations

¹ 2C2T-Centre for Textile Science and Technology, University of Minho, 4800-058 Guimarães, Portugal.
² Security and Disruptive Technologies Research Centre, National Research Council Canada, Ottawa, Ontario K1A 0R6, Canada.
³ Leibniz-Institut für Polymerforschung Dresden e.V. (IPF), Hohe Str. 6, 01069 Dresden, Germany.
⁴ Aerospace Research Centre, National Research Council Canada, 5145 Decelles Avenue, Montreal, Quebec H3T 2B2, Canada.

Abstract

Integration of single-wall carbon nanotubes (SWCNTs) in the form of fabriclike sheets or other preformed assemblies (films, fibers, etc.) simplifies their handling and allows for composites with higher nanotube contents, which is needed to better exploit their outstanding properties and achieve multifunctional materials with improved performance. Here, we show the development of p-type SWCNT-thermoplastic polyurethane (TPU) fabric materials with a wide range of SWCNT contents (from 5 to 90 wt %) by employing a one-step filtration method using a suspension of SWCNTs in a TPU solvent/nonsolvent mixture. The mechanical and thermoelectric (TE) properties of these SWCNT-TPU nanocomposites were tailored by varying the SWCNT/TPU wt % ratio, achieving significant advantages relative to the pristine SWCNT buckypaper (BP) sheets in terms of strength and stretchability. In particular, the SWCNT-TPU nanocomposite with a 50/50 wt % ratio composition (equivalent to 15 vol % of SWCNTs) shows a power factor (PF) of 57 μW m^-1 K^-2, slightly higher compared to the PF of the SWCNT BP prepared under the same conditions (54 μW m^-1 K^-2), while its mechanical properties significantly increased (e.g., ∼7-, 25-, and 250-fold improvements in stiffness, strength, and tensile toughness, respectively). These results represent a significant step toward the development of easy-to-process self-supporting and stretchable materials with robust mechanical properties for flexible thermoelectric devices.