Surface microstructural engineering of continuous fibers as one-dimensional multifunctional fiber materials for wearable electronic applications

The rapid progress in advanced functional fibers (AFFs) offers unique superiorities in wearable electronics, artificial intelligence, and healthcare monitoring. However, there remain considerable challenges for AFFs to fulfill specific requirements of advanced applications due to their low electrical outputs, limitation in materials selection, and difficulty in regulating microstructures on narrow and curved surface of the fibers. In this study, fabricating and regulating honeycomb porous microstructures (HPMs) on one-dimensional nonplanar fiber surfaces were proposed and systematically studied for developing AFFs with customized functionalities. As a demonstration of application, multifunctional silver-plated nylon fibers surface-engineered with HPMs (SNF@HPMs) were developed with the assistance of the BF method and were further fabricated into SNF@HPMs-based triboelectric nanogenerator (SNF@HPMs-TENG). The SNF@HPMs-TENG showed considerable electrical performances with a power density of 390.8 mW/m² and good long-term stability, which can power portable electronics as capacitors, calculator, watch, and light up 150 LEDs. Moreover, a self-powered wearable sensor based on SNF@HPMs was also developed for monitoring the bending, tactile, and frictional stimuli in a real-time manner. The comprehension of HPMs mechanism on nonplanar fiber surface and demonstrated capability of the SNF@HPMs-TENG provide insights and guidance in regulating microstructures of fiber materials for developing AFFs with customizable functionalities.