Revealed mechanism of 3D-open-microarray boosting exoelectrogens Geobacter enrichment and extracellular electron transfer for high power generation in microbial fuel cells

Abstract

The anode enables raised microbial fuel cells (MFCs) performance via in-situ growth electroactive material. However, the role of fabricated microstructures in electroactive bacteria loading and extracellular electron transfer (EET) has been paid less attention. Here, MoS2 nanosheets are custom grown on carbon cloth to construct anode models with diverse surface microstructures. Surprisingly, the 3D-MoS2/NS-CC anode only 0.85 d enables the MFC to be started and achieves a maximum power density of 3.85 W/m², which is significantly faster and higher than that of 2D-MoS2/NS-CC (3.6 d, 2.75 W/m²) and CC (4.46 d, 1.98 W/m²). As for the mechanism of 3D-MoS2/NSCC boosting MFC performance, this is attributed to the 3D-open-microarray preventing electroactive bacteria from shedding and facilitating to the establishment of excellent EET channels through the formed hybrid cell-electrode systems and Geobacter enrichment of up to 86.1 %. This research provides promising guidance for integrating nanomaterials and architecture to construct high-performance anodes in MFCs.