Review and Evaluation of Ceramic‐Stabilized Iron Oxides for Use as Energy Storage Based on Iron‐Steam Process

Several studies have reported about different hydrogen production and storage materials. The use of metal oxides, particularly iron oxides, as hydrogen storage materials offers a promising solution to bridge hydrogen production and utilization. The iron‐steam process, dating back to the 18th century, leverages iron's ability to bind oxygen from steam, producing hydrogen and iron oxides. This study revisits the iron/iron oxide system for its dual application as a hydrogen storage medium and as an energy carrier in systems like fuel cells. When integrated with high‐temperature electrolysis and fuel cells, this system can efficiently operate between 600 and 1000 °C. The key to long‐term performance lies in understanding the formation and stability of oxygen‐binding structures. Stabilizing the iron oxides for cycling procedures with other metal oxides like Al 2 O 3 , SiO 2 , and CaO is inevitable. Ceramic‐stabilized iron oxide pellets offer advantages including high cycling capability, efficient charge/discharge operations, and potential syngas production. They are particularly suitable for heavy goods vehicles, short‐term storage, and large‐scale industrial applications. Critical process parameters for the iron oxide material and process design must be investigated if an accurate assessment of the performance of this hydrogen storage concept is to be transferred into efficient practice.