Single-Step Additive Manufacturing of Monolithic MXene Architectures for Integrated Wireless Energy Storage in Wearable Electronics

Abstract

Flexible energy storage devices with integrated wireless charging units enable compact, mobile power solutions for next-generation wearable electronics. However, conventional multistep hybrid fabrication processes often suffer from interfacial energy losses and limited mechanical flexibility, hindering seamless integration. Here, we present a single-step extrusion printing strategy utilizing rheologically tailored Ti₃C₂ MXene inks to simultaneously print interdigitated microsupercapacitors (MSCs) and wireless charging coils. This approach leverages shear-aligned MXene nanochannels to construct bifunctional modules that achieve 51.9% wireless power transfer efficiency, high areal capacitance (59.36 mF cm^–2), and high energy density (26.71 μWh cm^–2), effectively addressing traditional interfacial limitations. The integrated device exhibits excellent mechanical robustness, maintaining capacitance stability under various bending angles or 10,000 folding cycles. Following only 8 min of wireless charging, it delivers a peak power output of 1.3 mW, outperforming existing planar MSCs. Notably, a 140 s charging period enables continuous operation of a humidity and temperature sensor for 43 min, setting a record-high charge-to-use ratio of 18.4. This study establishes a groundbreaking paradigm for seamless wireless power-storage integration that offers transformative design principles and fabrication strategies for next-generation wearable electronics.