@article{ab0afa31afa94765b71bf54d27d105e4,
title = "Facile Fabrication of Flexible and High-Performing Thermoelectrics by Direct Laser Printing on Plastic Foil",
abstract = "The emerging fields of wearables and the Internet of Things introduce the need for electronics and power sources with unconventional form factors: large area, customizable shape, and flexibility. Thermoelectric (TE) generators can power those systems by converting abundant waste heat into electricity, whereas the versatility of additive manufacturing suits heterogeneous form factors. Here, additive manufacturing of high-performing flexible TEs is proposed. Maskless and large-area patterning of Bi2Te3-based films is performed by laser powder bed fusion directly on plastic foil. Mechanical interlocking allows simultaneous patterning, sintering, and attachment of the films to the substrate without using organic binders that jeopardize the final performance. Material waste could be minimized by recycling the unexposed powder. The particular microstructure of the laser-printed material renders the—otherwise brittle—Bi2Te3 films highly flexible despite their high thickness. The films survive 500 extreme-bending cycles to a 0.76 mm radius. Power factors above 1500 µW m−1K−2 and a record-low sheet resistance for flexible TEs of 0.4 Ω sq−1 are achieved, leading to unprecedented potential for power generation. This versatile fabrication route enables innovative implementations, such as cuttable arrays adapting to specific applications in self-powered sensing, and energy harvesting from unusual scenarios like human skin and curved hot surfaces.",
keywords = "bismuth telluride, energy harvesting, flexible electronics, laser powder bed fusion, printed thermoelectrics",
author = "Yuan Tian and Isidro Florenciano and Heyi Xia and Qiyuan Li and Baysal, {Hasan Emre} and Daiman Zhu and Eduardo Ramunni and Sebastian Meyers and Yu, {Tzu Yi} and Kitty Baert and Tom Hauffman and Souhaila Nider and Berfu G{\"o}ksel and Francisco Molina-Lopez",
note = "Funding Information: Y.T. is a Fundamental Research Ph.D. fellow at FWO and this work was supported by the Research Foundation – Flanders (project number 11E2621N); I.F. acknowledges the support of the Internal Funds KU Leuven, C1 project C14/21/078; H.X.: The project (40007563 CONNECT,) has received funding from the FWO (project G0J4922N) and F.R.S.‐FNRS under the Excellence of Science (EOS) program. H.E.B. and T.‐Y.Y.: The research was further supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program: grant agreement 948922 – 3DALIGN. D.Z. acknowledges the Research Foundation – Flanders (project number 1287021N). This work was also supported by KU Leuven BOF‐SMINF internal funding KA/20/037. F.M.‐L. acknowledges the support of Interne Fondsen KU Leuven/Internal Funds KU Leuven (STG/19/004). K.B. and T.H. acknowledge FWO for infrastructure funding (XPS): I002818N. The authors thank Renaud Hendrik from Lubrizol for providing free Solsperse Hyperdispersants samples. The authors also thank Dr. Julian M. Mace from Dupont Teijin Films UK Ltd for providing samples of polyimide films (75 and 55 µm thick). The authors thank the opportunity to work at KU Leuven Institute on Additive Manufacturing and the warm help from Prof. Brecht Van Hooreweder and Yannis Kinds. The authors thank Prof. Maria Seo (Jin Won)'s support in TEM characterization. The authors thank Prof. Erin Koos and Dr. Anja Vananroye for the rheology measurement and results analysis. The authors thank Prof. Annabel Braem's support in Zeta potential measurement and XPS. The authors thank the support from the Materials Engineering Department: Wout Veulemans for particle size distribution analysis, advice in powder processing, and arranging room for the F.M.‐L. group in the powder lab; Joris Van Dyck for furnace assistance; Iris Cuppens for support regarding chemical experiments; Danny Winant for TGA measurements and liquid nitrogen supply. Human participant consent declaration: The final device was attached with tape on a person's arm with the hot side in direct contact with the skin and the cold side separated via a paper spacer. The human volunteer, one of the authors, took part following informed consent. Publisher Copyright: {\textcopyright} 2023 Wiley-VCH GmbH.",
year = "2024",
month = apr,
day = "11",
doi = "10.1002/adma.202307945",
language = "English",
volume = "36",
journal = "Advanced Materials",
issn = "1521-4095",
publisher = "Wiley , John Wiley & Sons,",
number = "15",
}