Kirigami Patterning of MXene/Bacterial Cellulose Composite Paper for All-Solid-State Stretchable Micro-Supercapacitor Arrays.

Stretchable micropower sources with high energy density and stability under repeated tensile deformation are key components of flexible/wearable microelectronics. Herein, through the combination of strain engineering and modulation of the interlayer spacing, freestanding and lightweight MXene/bacterial cellulose (BC) composite papers with excellent mechanical stability and a high electrochemical performance are first designed and prepared via a facile all-solution-based paper-making process. Following a simple laser-cutting kirigami patterning process, bendable, twistable, and stretchable all-solid-state micro-supercapacitor arrays (MSCAs) are further fabricated. As expected, benefiting from the high-performance MXene/BC composite electrodes and rational sectional structural design, the resulting kirigami MSCAs exhibit a high areal capacitance of 111.5 mF cm-2, and are stable upon stretching of up to 100% elongation, and in bent or twisted states. The demonstrated combination of an all-solution-based MXene/BC composite paper-making method and an easily manipulated laser-cutting kirigami patterning technique enables the fabrication of MXene-based deformable all-solid-state planar MSCAs in a simple and efficient manner while achieving excellent areal performance metrics and high stretchability, making them promising micropower sources that are compatible with flexible/wearable microelectronics.