Straightforward stamping manufacturing of flexible in-plane supercapacitor using wood-derived robust film and Ti3C2Tx inks

The rapid proliferation of portable smart electronics has significantly expanded the demand for flexible energy storage devices. Flexible supercapacitor (FSC), characterized by long lifetime, high power density, and portability, is an ideal power source for smart electronics. However, key challenges remain in developing robust, sustainable, and cost-effective electrode substrates and achieving rapid fabrication of FSCs with tailored electrode patterns. Herein, a mechanically strong wood-derived film is applied as the flexible substrate for stamping of Ti 3 C 2 T x inks to readily construct a high-performance in-plane FSC. The wood-derived film with a dense layered structure, high crystallinity, and fiber-oriented characteristics is prepared from natural vertical-section wood via cell wall softening engineering in combination with densification treatment, which exhibits excellent mechanical performance, flexibility, and foldability. By direct stamping Ti 3 C 2 T x inks on wood-derived film surface followed by drying, a flexible interdigitated electrode with stable electrical conductivity is achieved, enabling the rapid manufacturing of in-plane FSC. The developed FSC delivers favorable areal capacitance of 57.8 mF·cm −2 at 0.2 mA·cm −2 , and high energy density of 2.89 μWh·cm −2 at 60 μW·cm −2 . Furthermore, the FSC maintains stable capacitive behavior in the flexural state or after cyclic bending. Collectively, the integration of wood-derived film with Ti 3 C 2 T x inks for producing FSC via a stamping approach offers a sustainable strategy for the rapid manufacture of portable energy storage devices.