The article "Cellulose-based smart materials: Novel synthesis techniques, properties, and applications in energy storage and conversion devices" by Bishnoi et al. (2024) reviews the advancements in cellulose-based materials, particularly hydrogels, for energy storage and conversion applications. The authors discuss the unique properties of nanocellulose, such as high aspect ratio, biocompatibility, and renewability, which make them suitable for various applications. They explore the extraction sources and solvents used for dissolving cellulose, including ionic liquids (ILs), N-methylmorpholine N-oxide (NMMO), sodium hydroxide/urea, and deep eutectic solvents (DESs). The article also covers the preparation methods of hydrogels, including physical cross-linking techniques like freeze-thawing and radiation-induced techniques, as well as chemical cross-linking methods such as chain growth polymerization, irradiation polymerization, and step-growth polymerization. The properties of hydrogels, such as self-healing, transparency, strength, and swelling behavior, are discussed, along with their applications in flexible batteries, fuel cells, solar cells, and flexible supercapacitors. The authors conclude by highlighting existing challenges and recent findings in the field, emphasizing the potential of cellulose-based materials in addressing the increasing demands of energy storage systems.The article "Cellulose-based smart materials: Novel synthesis techniques, properties, and applications in energy storage and conversion devices" by Bishnoi et al. (2024) reviews the advancements in cellulose-based materials, particularly hydrogels, for energy storage and conversion applications. The authors discuss the unique properties of nanocellulose, such as high aspect ratio, biocompatibility, and renewability, which make them suitable for various applications. They explore the extraction sources and solvents used for dissolving cellulose, including ionic liquids (ILs), N-methylmorpholine N-oxide (NMMO), sodium hydroxide/urea, and deep eutectic solvents (DESs). The article also covers the preparation methods of hydrogels, including physical cross-linking techniques like freeze-thawing and radiation-induced techniques, as well as chemical cross-linking methods such as chain growth polymerization, irradiation polymerization, and step-growth polymerization. The properties of hydrogels, such as self-healing, transparency, strength, and swelling behavior, are discussed, along with their applications in flexible batteries, fuel cells, solar cells, and flexible supercapacitors. The authors conclude by highlighting existing challenges and recent findings in the field, emphasizing the potential of cellulose-based materials in addressing the increasing demands of energy storage systems.