Highly Responsive Soft Electrothermal Actuator with High-Output Force Based on Polydimethylsiloxane (PDMS)-Coated Carbon Nanotube (CNT) Sponge

Abstract

Recently, soft actuators have been found to have great potential for various applications due to their ability to be mechanically reconfigured in response to external stimuli. However, the balance between output force and considerable strain constrains their potential for further application. In this work, a novel soft electrothermal actuator was fabricated by a polydimethylsiloxane (PDMS)-coated carbon nanotube sponge (CNTS). The results showed that CNTS was heated to 365 °C in ∼1 s when triggered by a voltage of 3.5 V. Consequently, due to the large amount of air inside, the actuator expanded in 2.9 s, lifting up to ∼50 times its weight, indicating an ultrafast response and powerful output force. In addition, even in water, the soft actuator showed quick response at a voltage of 6 V. This air-expand strategy and soft actuator design is believed to open a new horizon in the development of electronic textiles, smart soft robots, and so on.