FTO ligulate petals interconnected 3D- porous iron surface for enhanced interfacial interactions with exoelectrogenic bacteria

Abstract

Microbial fuel cells (MFCs) are a promising sustainable energy technology, with the bio-active anode playing a crucial role in their performance. The present study demonstrates a bio-active iron-based electrode that enhances bacterial adhesion and electron conductivity. The bacterial survivability on the electrode can enhanced by decorating its active porous framework with Fe₂TiO₅ (FTO) composite. These particles not only facilitate bacterial activity for electron transfer processes but also enhances the anode cell potential in the assembled double-chambered MFC. A superior specific surface area of 289.06 m²/g, satisfactory average surface roughness of 2.506 µm, and reduced charge transfer resistance of 12.89 × 10⁰ Ω cm² compared to 18.68 × 10⁰ Ω cm² for the Fe/0.2FTO and Fe electrodes were achieved. MFCs equipped with the Fe/0.2FTO anode yield a maximum power density of 1710.39 mW/m² at a current density of 2.13 mA/m², which is superior to that of Fe anodes. Anode biofilm morphology and surface texture demonstrated that the anode provides sufficient sites and mass transport pathways for exoelectrogenic bacterial species, promoting improved bacterial activity in mature biofilms. Thus, the FTO decorated porous 3D-framework anode with tunable surface properties, acts as a promising platform for sustained bacterial activity and stable operation of MFCs.