Aqueous Inks of Pristine Graphene for 3D Printed Microsupercapacitors with High Capacitance

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Three-dimensional (3D) printing offers a sustainable method for creating high-performance energy storage devices.
• Miniaturized energy storage is crucial for on-chip technologies requiring energy autonomy.

Purpose of the Study:

• To demonstrate 3D printed microsupercapacitor electrodes from pristine graphene aqueous inks.
• To achieve high performance without high-temperature processing or additives.

Main Methods:

• Fabrication of microsupercapacitor electrodes using 3D printing with aqueous graphene inks.
• Characterization of electrochemical performance, including areal capacitance and energy/power densities.
• Testing of device stability through repeated voltage holding.

Main Results:

• Achieved an areal capacitance of 1.57 F cm⁻² at 2 mA cm⁻², with 72% retention after voltage holding tests.
• Demonstrated areal power density of 0.968 mW cm⁻² and areal energy density of 51.2 μWh cm⁻².
• Developed current collector-free interdigitated microsupercapacitors with gel electrolytes exhibiting near liquid-like ion transport.

Conclusions:

• 3D printing provides a sustainable, low-cost approach for efficient energy storage devices with programmable geometry.
• The developed graphene-based microsupercapacitors outperform previously reported printed carbon-based supercapacitors.
• This method enables the fabrication of advanced energy storage solutions for miniaturized electronic systems.