Ultrafast yet Controllable Dual-Responsive All-Carbon Actuators for Implementing Unusual Mechanical Movements

Abstract

Synthetic soft actuators with the integration of fast response speed, large-scale displacement, and precise control over deformation direction are highly demanded for implementing agile and precise mechanical movements in smart robots, artificial muscles, and biomimetic devices. In this work, ultrafast yet controllable all-carbon actuators are created based on graphene oxide and oriented carbon nanotubes. This all-carbon actuator shows humidity- and near infrared light-induced actuation with unprecedented performance integration, including ultrafast response (0.08 s), ultralarge deformation (angle change per length 70 °/mm), on-demand control over deformation direction (directional bending and chiral twisting), and high reversibility (no detectable fatigue after 10 000 cycles). Impressively, the remarkable actuation performances allow the all-carbon actuator to implement diverse unusual movements, including light-triggered jumping vertically at a speed of 250 mm/s, rolling horizontally at a speed of 12 mm/s, throwing an object at a speed of 505 mm/s, arresting a high-speed object (335 mm/s), as well as humidity-triggered lifting of an object instantly (0.34 s).