Three-dimensional stretchable fabric-based electrode for supercapacitors prepared by electrostatic flocking

The three-dimensional vertical-array scaffolds can be constructed by electrostatic flocking with quite high efficiency and low cost for large-area applications. Herein, we have fabricated stretchable and highly conductive fabric base resulting from the strong interaction between acid-functionalized carbon nanotubes (AC-MWNTs) and cationic cotton/spandex fabric. Then the electrostatic flocking was applied for the first time to implant vertical arrays of carbon fibers onto conductive fabrics, accompanied by deposition of nano-MnO₂ to construct 3D stretchable fabric-based electrode with multistage array structure (MnO₂@C-MC/S₁-2). The composite binder-free electrode provided high conductivity and capacitive efficiency as well as the ideal electrochemical reversibility under tension. Furthermore, asymmetric solid-state supercapacitors were assembled using MnO₂@C-MC/S₁-2 as the positive electrode, C-MC/S₁ with higher C₁ loaded as the negative electrode, which exhibited maximum energy density of 1.70 mWh/cm² (at a power density of 21.82 mW/cm²) and power density of 347.34 mW/cm² (at an energy density of 0.91 mWh/cm²). The facile electrostatic flocking process with simplicity of operation and economic efficiency is both straightforward and cost-effective for fabricating three-dimensional electrodes for wearable energy storage applications.