Elastic Deformation of Cellulose/Lignin-Based Anode for Rejuvenating Aged Mix-Cultured Electroactive Biofilms

Electroactive biofilms (EABs) are essential components of both natural and artificial bio-electrochemical systems (BESs). However, the inevitable decay of EABs during prolonged operation can diminish their performance. In this contribution, an effective and noninvasive strategy for rejuvenating aging biofilms by the elastic deformation of anode material is approved. The synthesized wood tracheid-like structures anode material showed excellent compressibility and fatigue resistance in a wet state. The findings indicate that after the elastic deformation of the anode, aged biofilm exhibited a 37.5% increase in metabolic activity, and multi-SIM images confirmed the removal of dead cells. Analysis of the extruded substance revealed a significant removal of loosely bound extracellular polymeric substance which doesn't contribute directly to electron transfer. Community analysis demonstrated the rejuvenation process suppressed the ecological competition from non-exoelectrogens. Overall, there is a notable 25.97% increase in power density following the elastic deformation of the anode. Additionally, ion diffusion, specific capacitance, and catalytic response current all improved. To the knowledge, this is the first report employing an anode deformation strategy to restore decayed mix-cultured electroactive biofilm, which is vital for the practical long-term application of BESs. This work also offers new insights into the mechanical influence of anode materials on microorganisms.