A critical review of biofuel cell cathodes

Biofuel cell cathodes (BFCs) employing enzymatic or microorganism-based electrocatalysts have attracted significant attention for their ability to oxidize fuel and reduce an oxidizing agent at the electrodes. They have a variety of applications, including wastewater treatment, as biosensors, and in portable devices. However, their limited lifespan and low power density present challenges for their future potential and developments. Most BFCs that have been developed are capable of supplying energy only to transiently implanted biomedical devices. Materials with nanoscale dimensions have the potential to enhance the efficiency of BFCs. This contribution critically examines the functionality of fuel cell cathodes and explores a wide range of potential applications. It presents a comprehensive analysis of the current trajectory of biofuel cell development, highlighting limitations of BFCs and providing recommendations for future research directions. © 2025 Elsevier B.V., All rights reserved.