Antibacterial MnS/Co-SNC cathode catalysts for high-performance microbial fuel cells

Area of Science:

• Electrochemistry
• Materials Science
• Biotechnology

Background:

• Microbial fuel cells (MFCs) face challenges in practical application due to slow oxygen reduction reaction (ORR) kinetics and cathode biofouling.
• Existing catalysts often struggle to address both issues simultaneously, limiting MFC performance and longevity.

Purpose of the Study:

• To develop a bifunctional catalyst (MnS/Co-SNC) capable of enhancing ORR activity and providing antibacterial properties.
• To investigate the catalyst's performance in single-chamber MFCs for sustainable energy generation.

Main Methods:

• Synthesis of a MnS/Co co-anchored N-doped carbon catalyst (MnS/Co-SNC) derived from ZIF-67.
• Electrochemical characterization of the catalyst's ORR performance in alkaline media.
• Evaluation of the catalyst's antibacterial activity and biofilm suppression.
• Testing the catalyst as an air-cathode in single-chamber MFCs to assess power density and stability.

Main Results:

• The MnS/Co-SNC catalyst demonstrated superior ORR onset potential (0.92 V) and half-wave potential (0.88 V) compared to commercial Pt/C.
• The catalyst exhibited significant antibacterial activity, effectively inhibiting biofilm formation.
• In single-chamber MFCs, the MnS/Co-SNC cathode achieved a maximum power density of 1400 mW m⁻² and maintained stable voltage for over 120 hours.
• The catalyst outperformed other state-of-the-art non-precious metal catalysts.

Conclusions:

• The developed MnS/Co-SNC catalyst offers a synergistic solution to enhance MFC performance by improving ORR kinetics and combating biofouling.
• This multifunctional catalyst represents a significant advancement for the practical application of MFCs in sustainable energy generation.