When Cellulose Moves: Smart Sensors and Actuators

Cellulose, the most abundant biopolymer on Earth, has rapidly gained attention as a key component in the development of smart materials capable of dynamic and adaptive behavior. This review highlights the unique motion and actuation capabilities of cellulose-based systems, focusing on their ability to convert external stimuli into mechanical movement. The recent progress in cellulose-derived soft actuators that respond to moisture, electric fields, thermal and light input, and magnetic forces is detailed – enabling programmable shape changes, bending, twisting, and locomotion. Alongside these, cellulose-based soft sensors that transduce environmental cues though magnetic, resistive and capacitive mechanisms are examined. Special emphasis is placed on the synergy between sensing and actuation in multifunctional devices that mimic natural movement and responsiveness. Applications in wearable devices, soft robotics, biomedical systems, energy harvesting, smart packaging, and bioinspired technologies are explored to demonstrate the practical potential of these materials. The challenges in achieving robust, reversible, and multi-stimuli-responsive motion are also addressed, and future directions for scaling up and integrating cellulose-based smart systems into real-world applications are proposed.