Bioelectrochemical carbon monoxide methanation in mixed-culture microbial electrolysis cells: Performance, electron transfer pathways and microbial succession.

Decreasing cathodic potential from -0.90 to -1.05 V in microbial electrolysis cells enhances methane production from CO by over tenfold, reaching 1.410 mmol.

• Why it matters: Converting toxic CO into methane via bioelectrochemical methods addresses the need for sustainable carbon resource recovery and industrial waste valorization, filling a critical knowledge gap.
• What they did: The study used a mixed-culture microbial electrolysis cell, analyzing electron transfer pathways, biofilm development, and microbial community shifts through electrochemical, spectroscopic, and genetic techniques.
• The result: Findings reveal a dual electron-uptake network, reduced charge transfer resistance, and enrichment of key microbes, enabling more efficient bio-methanation and advancing renewable biomethane production technologies.