Dual-Stimuli Responsive Carbon Nanotube Sponge-PDMS Amphibious Actuator

A dual-stimuli responsive soft actuator based on the three-dimensional (3D) porous carbon nanotube (CNT) sponge and its composite with polydimethylsiloxane (PDMS) was developed, which can realize both electrothermal and electrochemical actuation. The bimorph actuator exhibited a bending curvature of 0.32 cm^-1·W^-1 under electrothermal stimulation on land. The displacement of the electrochemical actuator could reach 4 mm under a 5 V applied voltage in liquid. The dual-responsive actuator has demonstrated the applications on multi-functional amphibious soft robots as a crawling robot like an inchworm, a gripper to grasp and transport the cargo and an underwater robot kicking a ball. Our study presents the versatility of the CNT sponge-based actuator, which can be used both on land and in water.