A Redox-Mediated Iron-Air Fuel Cell for Sustainable and Scalable Power Generation

Abstract

Pursuing carbon neutrality has invigorated extensive investigations into sustainable and cost-effective power sources. Iron-air batteries (IAB) have emerged as a promising option due to their high energy density, low cost, and environmental friendliness. However, conventional IABs grapple with issues such as electrode passivation, low round-trip energy efficiency, and parasitic hydrogen evolution. This study introduces a redox-mediated iron-air fuel cell (RM-IAFC) to surmount these limitations. The RM-IAFC employs a pair of redox mediators, respectively, in anolyte and catholyte tanks, enabling the iron oxidation and oxygen reduction reaction processes to be liberated from the electrodes. This configuration decouples energy storage and power generation, allowing fast refueling and offering operation flexibility and scalability while eliminating the need for expensive catalysts. With these salient features, the RM-IAFC paves the way for sustainable and scalable power generation, particularly for stationary applications.