A bioelectrocatalytic glucose oxidation cascade for energy-efficient electrocatalysis applications

Area of Science:

• Biotechnology and Green Chemistry
• Electrocatalysis and Energy Storage

Background:

• Hydrogen energy and zinc-air batteries (ZABs) are promising clean energy technologies.
• The oxygen evolution reaction (OER) in these systems suffers from high overpotential and slow kinetics, limiting efficiency.

Purpose of the Study:

• To develop a green and efficient bioelectrocatalytic cascade system to overcome OER limitations.
• To reduce energy consumption in water splitting and ZAB charging.
• To enable co-production of high-value gluconic acid.

Main Methods:

• Utilized nitrogen-doped carbon nanotubes (N-CNTs) as a support and electrocatalyst.
• Immobilized glucose oxidase (GOx) on N-CNTs for glucose oxidation.
• Developed in situ catalytic decomposition of hydrogen peroxide (H2O2) byproduct.

Main Results:

• Achieved a current density of 10 mA cm⁻² at a low potential of 1.60 V for hydrogen evolution.
• Demonstrated significant reduction in overpotentials for water splitting and ZAB charging.
• ZABs with the system showed high power density and excellent cycling stability.

Conclusions:

• The bioelectrocatalytic cascade system offers an energy-saving and high-efficiency strategy.
• Bifunctional bioelectrochemical catalysts are key for efficient hydrogen production and biomass valorization.
• This approach paves the way for sustainable energy solutions and valuable chemical co-production.