Sustainable Cellulose Ionogels With Promising Physical Structure, Properties, and Applications

ABSTRACT As an emerging green functional material, cellulose ionogels combine the renewability of cellulose with the unique physicochemical properties of ionic liquids, demonstrating multiscale tunable structures and multifunctional characteristics. This review systematically elaborates the hierarchical structural design from molecular‐scale mechanisms to macroscopic architectures, including porous networks, fibrous assemblies, and phase‐separated morphologies at nano/micro scales, as well as complex configurations achieved through advanced techniques such as 3D printing. These finely tailored structures endow the material with remarkable mechanical properties, high ionic conductivity, broad electrochemical windows, and intelligent responsiveness to thermal, humidity, and strain stimuli. Based on these attributes, cellulose ionogels exhibit broad application prospects in flexible sensors, electronic skin, supercapacitors, flexible energy storage devices, soft robotics, and biomedical fields. Finally, this article discusses current challenges and future development directions, highlighting the critical role of cellulose ionogels in advancing sustainable electronics and energy technologies.