Riveted Interconnections of Capacitance-Matched MXene-Based Yarn Supercapacitors Enable Seamless Energy Integration...

Electronic textiles are a transformative technology set to revolutionize next-generation wearable devices. However, a major challenge is making efficient yarn-based energy systems that power flexible wearables while blending seamlessly into textiles for unobstructed applications. Herein, 2D materials-coated yarn supercapacitors (YSCs) are designed, offering a promising solution through capacitance-matched electrode fabrication and a novel customizable riveted interconnection strategy for textile integration. MXene-coated cotton yarns (negative electrode) achieve a remarkable specific capacitance of ≈7 360 mF cm^-2 (≈536 F g^-1). To complement the negative electrode, a positive yarn electrode (rGO/MoS₂) is developed through a tailored synthesis process. A device fabrication strategy based on matching the capacitance of the yarn electrodes enhances the performance of YSCs, achieving an impressive specific capacitance of ≈658 mF cm^-2 (≈53 F g^-1), power density of ≈8,147 μW cm^-2 (≈650 W kg^-1), and energy density of ≈154.5 μWh cm^-2 (≈12.3 Wh kg^-1). The practical applicability of the YSCs is demonstrated via a novel yet simple integration design, whereby YSCs are connected to conductive rivets, which serve as buttons capable of toggling charge/discharge and easy removal from clothes for washing. The advancements made in this work enable on-the-go powering of wearable health systems, displays, and the Internet of things.