Benjamin Erable

The decrease in the electrochemical activity of multi‐species microbial anodes in bioelectrochemical systems is the main bottleneck to overcome for bringing these technologies one‐step closer to the industrialization stage. In this study, microsized stainless steel electrodes were implemented to investigate the distinctive electrochemical behavior of salt marsh electroactive biofilms (EABs). Four main temporal stages of biocolonization and electrochemical activity were thoroughly described. Maximum biofilm growth rate, high viability and high extracellular protein matrix content favored the increasing electrochemical activity of the EAB up to its maximum current peak. Then, when gradual fall in current became irreversible, biofilm growth rate decreased together with dead cells accumulation and an increase for extracellular polysaccharides. In addition, analyses of microbial populations showed a shift from Marinobacterium spp. to Desulfuromonas spp. These findings suggest a chemical and microbial temporal evolution of the EAB, which can be directly correlated to the electrochemical performance of the bioanode.