Silk‐Derived and Silk‐Based Composite Materials for Electrochemical Energy Storage

The increasing demand for sustainable energy storage technologies has increased interest in bio‐based functional materials. Biological‐based materials such as silk fibroin from mulberry ( Bombyx mori ) and non‐mulberry silks such as Eri ( Philosamia ricini ), Muga ( Antheraea assamensis ), and Tasar ( Antheraea mylitta, Antheraea pernyi ) are among the potential applications of biopolymers for electrochemical energy storage and flexible electronics. The semi‐crystalline substructure of silk fibroin, containing β‐sheet domains, possesses mechanical and thermal stability, and the different functional groups such as amine, hydroxyl, and carboxyl groups facilitate the integration of nanomaterials and conductive polymers such as polyaniline and polypyrrole. Among them, silk/polyaniline composites have shown high capacitance values with long cycle life stability, which supports their use in supercapacitor applications. This review focuses on current advances and challenges along with future perspectives for silk fibroin and silk‐based composites in energy storage technology. Despite enormous progress, some key challenges remain in maintaining high conductivity and large‐scale fabrication procedures. So, to overcome these limitations, future research needs to emphasize multifunctional and biodegradable device architectures, and also the ability of wild silks, including Muga and Eri, will be discovered, which can also offer advanced structural and functional advantages compared to traditional mulberry silk.