Enhanced medium-chain fatty acid production in electro-fermentation: synergistic mechanisms of multi-transition metals in high-entropy metal oxide-modified cathodes

Key Points

• The study aims to investigate the effect of high-entropy oxides on medium-chain fatty acid production during electro-fermentation.
• Utilized high-entropy oxides (HEOs) as modified cathodes in electro-fermentation processes.
• Conducted theoretical calculations on charge distribution and electronic properties.
• Measured electrochemical performance and microbial activity over fermentation stages.
• HEO-modified cathodes showed optimal electrochemical performance and microbial activity.
• Achieved maximum hexanoic acid production of 60.6 mmol C/L and 168.0 mmol C/L in two fermentation stages.
• Enhanced production compared to control and single-transition metal oxide groups by 6%-80%.