Polypyrrole-Modified Saccharomyces cerevisiae Used in Microbial Fuel Cell

Area of Science:

• Sustainable Energy
• Electrochemistry
• Biotechnology

Background:

• Microbial fuel cells (MFCs) offer sustainable energy from organic waste but face limitations due to slow charge transfer.
• Conductive polymers, like polypyrrole (PPy), can enhance MFC performance by improving charge transfer between cells and electrodes.

Purpose of the Study:

• To investigate the impact of polypyrrole (PPy) modification on yeast viability and electroactivity in microbial fuel cells (MFCs).
• To optimize PPy concentration for enhanced MFC performance and energy generation from wastewater.

Main Methods:

• Yeast cells were modified with varying concentrations of polypyrrole (PPy) (8, 25, 50, 100, 200 mM).
• Cell viability and proliferation were assessed using CFU/mL counts.
• Electrochemical performance was evaluated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV).
• Power density was measured using an external load in both laboratory solutions and wastewater.

Main Results:

• The 100 mM PPy concentration showed the highest impact on yeast proliferation (0.6 × 10⁷ CFU/mL).
• Differential pulse voltammetry (DPV) revealed that 50 mM PPy modification yielded the most significant current density, indicating improved charge transfer.
• The MFCs utilizing PPy-modified yeast achieved a power density of 12 mW/m² in wastewater, comparable to 45 mW/m² in laboratory solutions.

Conclusions:

• Polypyrrole modification effectively enhances yeast viability and electroactivity for MFC applications.
• Optimized PPy concentrations can significantly improve charge transfer and power generation in MFCs.
• PPy-modified yeast demonstrates potential for efficient energy recovery from wastewater, contributing to sustainable energy technologies.