Revisiting Current Trends in Electrode Assembly and Characterization Methodologies for Biofilm Applications

Microbial fuel cell (MFC) is a sustainable technology resulting from the synergism between biotechnology and electrochemistry, exploiting diverse fundamental aspects for the development of numerous applications, including wastewater treatment and energy production. Nevertheless, these devices currently present several limitations and operational restrictions associated with their performance, efficiency, durability, cost, and competitiveness against other technologies. Accordingly, the synthesis of nD nanomaterials (n = 0, 1, 2, and 3) of particular interest in MFCs, methods of assembling a biofilm-based electrode material, in situ and ex situ physicochemical characterizations, electrochemistry of materials, and phenomena controlling electron transfer mechanisms are critically revisited in order to identify the steps that determine the rate of electron transfer, while exploiting novel materials that enhance the interaction that arises between microorganisms and electrodes. This is expected to pave the way for the consolidation of this technology on a large scale to access untapped markets.