posted on 2020-03-04, 23:13authored byQiliang Fu, Yi Chen, Mathias Sorieul
Next-generation electronics
(e.g., substrate and
conductor) need to be high performance, multifunctional, and environmentally
friendly. Here, we report the creation of a fully wood-based flexible
electronics circuit meeting these requirements, where the substrate,
a strong, flexible and transparent wood film, is printed with a lignin-derived
carbon nanofibers conductive ink. The wood film fabrication involves
extensive removal of lignin and hemicellulose to tailor the nanostructure
of the material followed by collapsing of the cell walls. This process
preserves the original alignment of the cellulose nanofibers and promotes
their binding. The film is flexible, yet strong in fiber direction
with a Young’s modulus and a tensile strength of 49.9 GPa and
469.9 MPa, respectively. Furthermore, a sustainable and bio-based
conductive ink is formulated with lignin-derived carbon nanofibers.
The bio-based ink is printed on transparent wood film, and a strain
sensor application of the printed circuit is demonstrated. Combining
the transparent wood film with the conductive ink produces environmental
friendly and sustainable wood-based electronics for potential applications
such as flexible circuits and sensors. Moreover, we envision the potential
for a scalable and continuous fabrication process as well as end-of-life
recyclability.