Flexible, layered biofuel cells.

Area of Science:

• Biotechnology
• Electrochemistry
• Materials Science

Background:

• Biofuel cells require stacking to achieve practical voltages, similar to conventional batteries.
• Single biofuel cells typically produce less than 1 V.

Purpose of the Study:

• To develop a laminated biofuel cell stack with enhanced voltage output.
• To create a compact and efficient biofuel cell system for practical applications.

Main Methods:

• Fabricating bioanode and biocathode materials by immobilizing fructose dehydrogenase and bilirubin oxidase on carbon nanotube-decorated carbon fiber fabrics.
• Constructing a laminated triple-layer stack comprising bioanode fabrics, hydrogel electrolyte/fuel sheets, and biocathode fabrics.
• Measuring the open-circuit voltage and power output of the single cell and the laminated stack.

Main Results:

• The laminated triple-layer stack achieved an open-circuit voltage of 2.09 V, a 2.8-fold increase compared to a single cell (0.74 V).
• The total thickness of a single anode/gel/cathode set was only 1.1 mm.
• The 5 mm × 5 mm layered cell delivered a maximum power of 0.64 mW at 1.21 V, sufficient for powering light-emitting diodes.

Conclusions:

• A novel laminated biofuel cell stack design offers a significant voltage enhancement.
• The compact and efficient design demonstrates potential for powering low-power electronic devices.
• This approach provides a scalable method for increasing biofuel cell output voltage.