Fructose/dioxygen biofuel cell based on direct electron transfer-type bioelectrocatalysis.

Area of Science:

• Bioelectrochemistry
• Renewable Energy Technologies
• Enzyme Catalysis

Background:

• Development of efficient biofuel cells is crucial for sustainable energy.
• Direct electron transfer (DET) bioelectrocatalysis offers a mediator-free approach for biofuel cell design.
• Enzyme immobilization on electrode surfaces is key to enhancing catalytic activity and stability.

Purpose of the Study:

• To construct and characterize a novel one-compartment biofuel cell utilizing d-fructose dehydrogenase (FDH) and laccase (TsLAC) for DET bioelectrocatalysis.
• To investigate the catalytic performance of FDH and TsLAC as anode and cathode catalysts, respectively.
• To evaluate the overall performance of the constructed biofuel cell in terms of voltage, current, and power density.

Main Methods:

• FDH and TsLAC were immobilized on modified carbon paper electrodes (Ketjen black and carbon aerogel, respectively).
• Electrochemical techniques were employed to study the catalytic activity and electron transfer mechanisms of the immobilized enzymes.
• A one-compartment biofuel cell was assembled by integrating the FDH-modified anode and TsLAC-modified cathode without a separator.

Main Results:

• FDH exhibited strong adsorption and stable catalytic activity, producing a maximum current density of approximately 4 mA cm(-2) at pH 5.
• TsLAC demonstrated efficient dioxygen reduction with a catalytic current density of about 4 mA cm(-2), governed by mass transfer.
• The constructed one-compartment biofuel cell achieved an open-circuit voltage of 790 mV and a maximum power density of 850 microW cm(-2) at 410 mV.

Conclusions:

• The developed one-compartment biofuel cell design utilizing FDH and TsLAC is effective for direct electron transfer bioelectrocatalysis.
• The mediator-free system demonstrates promising performance for sustainable energy generation from d-fructose and dioxygen.
• Further optimization of enzyme immobilization and electrode materials could lead to enhanced biofuel cell efficiency.