Polydopamine/polypyrrole-modified graphite felt enhances biocompatibility for electroactive bacteria and power density of microbial fuel cell

The interactions between the microbes and the surface of an anode play an important role in capturing the respiratory electrons from bacteria in a microbial fuel cell (MFC). The chemical and electrochemical charac-teristics of the carbon material affect biofilm growth and direct electron transfer in MFCs. This study examined the electrodeposition of polydopamine (PDA) and polypyrrole (PPY) on graphite felt electrode (GF). The MFC with the modified PDA/PPY-GF reached 920 mW/m2, which was 1.5, 1.17, and 1.18 times higher than those of the GF, PDA-GF, and PPY-GF, respectively. PDA has superior hydrophilicity and adhesive force biofilm forma-tion, while PPY provides electrochemically active sites for microbial electron transfer. Raman spectroscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller surface area measurements, and contact angle analysis revealed the enhanced physicochemical properties of the carbon electrode. These results show that co -doped PDA/PPY provides a strategy for electroactive biofilm development and improves the bioelectrochemical performance in realistic MFC reactors.

Automated summary

The interactions between microbes and the anode surface are crucial for capturing respiratory electrons in microbial fuel cells (MFCs). The chemical and electrochemical characteristics of carbon materials affect biofilm growth and electron transfer in MFCs. This study investigated the electrodeposition of polydopamine (PDA) and polypyrrole (PPY) on a graphite felt electrode. The MFC with modified PDA/PPY-GF exhibited significantly higher electrochemical performance compared to other electrodes, demonstrating the potential of co-doped PDA/PPY to enhance biofilm development and improve bioelectrochemical performance in MFCs.