Wire-Shaped Supercapacitors with Organic Electrolytes Fabricated via Layer-by-Layer Assembly

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Wire-shaped supercapacitors (WSSs) offer flexibility and textile integration advantages.
• Existing WSS designs require optimization for performance and stability.

Purpose of the Study:

• To fabricate a thin, reproducible WSS with enhanced capacitance and extended voltage window.
• To investigate the impact of electrolyte composition on WSS performance and stability.

Main Methods:

• Layer-by-layer (LbL) assembly of multiwalled carbon nanotubes (MWCNTs) on a gold wire.
• Incorporation of vanadium oxide for pseudocapacitance enhancement.
• Formulation of an organic electrolyte (propylene carbonate-acetonitrile-lithium perchlorate-poly(methyl methacrylate)) with an extended voltage window of 1.6 V.

Main Results:

• Achieved an areal capacitance of 5.23 mF cm⁻² at 0.2 mA cm⁻².
• Demonstrated an energy density of 1.86 μW h cm⁻² and a power density of 8.5 mW cm⁻².
• Exhibited excellent cyclic stability with 94% capacitance retention after 10,000 cycles.

Conclusions:

• The developed LbL-assembled WSS shows significant potential for high-performance textile electronics.
• Optimized electrolyte composition is crucial for balancing WSS stability and performance.
• This scalable fabrication method paves the way for integrated energy storage in wearable devices.