FeO -Based Materials for Electrochemical Energy Storage

Iron oxides (FeO ), such as Fe₂O₃ and Fe₃O₄ materials, have attracted much attention because of their rich abundance, low cost, and environmental friendliness. However, FeO , which is similar to most transition metal oxides, possesses a poor rate capability and cycling life. Thus, FeO -based materials consisting of FeO , carbon, and metal-based materials have been widely explored. This article mainly discusses FeO -based materials (Fe₂O₃ and Fe₃O₄) for electrochemical energy storage applications, including supercapacitors and rechargeable batteries (e.g., lithium-ion batteries and sodium-ion batteries). Furthermore, future perspectives and challenges of FeO -based materials for electrochemical energy storage are briefly discussed.