Microfluidic Fabrication of Janus Triboelectric Fibers with Bamboo-Like Architecture for Motion Sensing Applications

Abstract

Fiber-based triboelectric nanogenerators (f-TENGs) hold great promise for healthcare applications, addressing increasing demand for wearables and self-powered devices in our aging society. To date, many co-axial multilayer fibers have been developed for the fabrication of stand-alone single-thread f-TENGs, whose developments are often constrained by low-throughput fabrication processes that require advanced techniques and additional assembly steps. Herein, we describe a novel Janus bamboo-like f-TENG for human motion sensing. With the microfluidic wet spinning (MWS) technique, polytetrafluoroethylene (PVDF) and thermoplastic polyurethane (TPU) were precisely distributed in two halves of Janus fibers, with PVDF as tribo-negative and TPU as tribo-positive materials separated by bamboo-like cavities. We demonstrated that such f-TENGs can be facilely integrated into wearable sensors for monitoring human body movements at different frequencies and motion amplitudes. The continuous and controlled fabrication of such f-TENGs enabled by MWS offers new opportunities for the future development of self-powered and miniaturized wearable devices.

Graphical Abstract

Keywords

Microfluidic wet spinning / Bamboo-like structure / Janus fiber / Triboelectric nanogenerator / Human motion monitoring

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Funding

China Scholarship Council

Empa - Swiss Federal Laboratories for Materials Science and Technology

RIGHTS & PERMISSIONS

The Author(s)