A Moss-Inspired Electroless Gold-Coating Strategy Toward Stretchable Fiber Conductors by Dry Spinning

Stretchable fiber conductors are appealing in the field of soft electronics due to their potential to be woven into fabrics leading to smart textile electronics. Coating highly conductive metal films onto elastic polymer fibers can be a potential strategy, however, it is nontrivial to achieve strong metal/polymer adhesion to avoid interfacial failure under large mechanical strains. Here, a novel moss-inspired gold-coating strategy by using an ultrathin gold nanowires (AuNWs)-seeded electroless deposition strategy to fabricate stretchable fiber conductors in a dry spinning process is reported. By optimizing Hildebrand's and Hansen's solubility parameter, the AuNWs are dispersed well in an elastomer matrix leading to the efficient scalable production of AuNWs-impregnated elastomeric fibers. Remarkably, these AuNWs can serve as seeds to promote conformal electroless deposition of gold films to substantially enhance the fiber conductivity. Such gold films resemble moss exhibiting strong adhesion to elastomeric polymer fibers because they have AuNWs roots embedded in the polymer matrix. With prestrained fibers, directional cracks along the axis are found, but they can be repaired reversibly when strains are reapplied. This leads to substantial conductivity enhancement. The fiber conductors can be woven into an everyday glove to exhibit superior strain-insensitivity without changing the intensity of the light-emitting diode under severe deformations.