Recent Advances in Enzyme-based Biofuel Cells Using Glucose Fuel: Achieving High Power Output and Enhanced Operational Stability

An enzyme-based biofuel cell (EBFC) is widely regarded as one of the most efficient power sources for bio-friendly and implantable medical devices, capable of converting electrochemical reactions into electrical currents under physiological conditions. However, despite its potential, the practical and commercial use of EBFCs is limited by their low power output and operational instability. Therefore, significant research efforts have focused on increasing power output and stability by improving electron transfer between enzymes and host electrodes and developing efficient enzyme immobilization techniques. However, most EBFCs produced by current methods still deliver unsatisfactory performance. A promising approach to address these challenges is the use of conductive linkers that promote favorable interfacial interactions between adjacent enzymes and between enzymes and host electrodes. These linkers can facilitate electron transfer and ensure robust enzyme immobilization. In addition, designing the host electrode with a 3D structure and a large surface area can further improve the areal energy performance. This perspective reviews the working principles, types, and electron transfer mechanisms of EBFC electrodes and explores how conductive linkers and 3D host electrodes can enhance the performance of EBFC electrodes. Finally, recent advances in integrating EBFCs into biomedical devices are described.