3D patterned fabric-based wearable micro-supercapacitor operating at high voltage by electrostatic actuation

Abstract

To address the energy storage needs of wearable electronics, this study developed high-performance, flexible micro-supercapacitors (MSCs) using 2D and 3D patterned fabric-based microelectrodes. The 2D electrodes were created via a screen-printing method with an omnidirectional pre-stretching strategy, while 3D array-structured electrodes were formed through electrostatic actuation. Nano-MnO₂ and Na_0.77MnO₂ were deposited to enhance pseudo-capacitive storage and widen the electrochemical window. The C-C/MnO₂-based MSCs exhibited a 21% pseudo-capacitance ratio, achieving an area-specific capacitance of 118.2 mF cm⁻² at 5 mV s⁻¹ and an energy density of 39.25 mWh cm⁻² at 0.21 mW cm⁻². These MSCs maintained 95.05%, 92.04%, and 89.74% of their capacitance under stretched, twisted, and folded conditions, respectively, and showed stable performance across temperatures from −20 °C to 60 °C. Additionally, C-C/Na_0.77MnO₂-based MSCs extended the electrochemical window to 1.6 V and retained 100.2% capacitance after 6500 cycles. This work offers innovative strategies for advancing portable and wearable electronic devices.