All-solid-state wire-shaped micro-supercapacitors: A microfluidic approach to core-shell structured bacterial...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Wire-shaped micro-supercapacitors (micro-SCs) offer structural advantages for wearable electronics.
• Current fabrication methods for continuous micro-SC production are complex and challenging.
• All-solid-state micro-SCs are desirable for their lightweight, flexibility, and mechanical stability.

Purpose of the Study:

• To introduce a novel microfluidic technique for synthesizing core-shell structured fibers.
• To fabricate high-performance, all-solid-state, wire-shaped micro-supercapacitors.
• To demonstrate the potential of these micro-SCs in wearable electronic applications.

Main Methods:

• A microfluidic technique was employed to synthesize core-shell structured fibers.
• Bacterial cellulose (BC) served as a scaffold, graphene (GN) enhanced electrical properties, and polypyrrole (PPy) formed the shell.
• A solid-state H3PO4/PVA gel electrolyte was utilized for the micro-supercapacitors.

Main Results:

• The developed micro-SCs exhibited a high specific capacitance of 162 mF cm⁻².
• An energy density of 96.5 mW h cm⁻² was achieved.
• Superior cycling stability was demonstrated, with 95.11% capacitance retention after 5000 cycles.

Conclusions:

• The microfluidic strategy enables the design of unique core-shell structured BC-GN/PPy fibers.
• This fabrication method is suitable for constructing high-performance micro-SCs.
• The developed micro-SCs hold significant promise for advanced wearable electronics.