Recent advances in iron oxide/graphene composites for flexible supercapacitors

Flexible supercapacitors (SCs) are pivotal in the development of wearable and portable electronic devices because of their exceptional power density, high charge/discharge rates, extended cycle life, lightweight, and flexibility. Graphene (G) -based macroscopic materials, such as one-dimensional fibers, two-dimensional films, and three-dimensional aerogels, exhibit a large specific surface area, low mass, excellent flexibility, and high conductivity. These properties make them highly suitable for use as flexible electrode materials in SCs. However, the low energy density of G -based materials hinders their application in certain fields. Iron oxide (Fe2O3) has garnered considerable attention as a negative electrode material because of its low cost, high theoretical capacity, and environmentally friendly nature. However, its practical application is limited because of its poor cycling stability, easy agglomeration, and low electrical conductivity. The combination of G with Fe2O3 to form a composite material not only addresses the issues of volume change and agglomeration associated with Fe2O3, but also establishes a robust conductive network that improves the electrochemical performance of composite electrodes. Therefore, the construction of SCs using Fe2O3/G composite electrodes has gained considerable research attention in recent years. We present a comprehensive review of the recent progress in the design of Fe2O3/G composites as electrode materials for flexible SCs. In addition, we discuss the current challenges and future prospects associated with the use of Fe2O3/G composites in flexible SCs.