Fully Printed Micro-Patterned Electrochemical Actuators

Submillimetre or micrometre scale electrically controlled soft actuators have immense potential in microrobotics, haptics, and biomedical applications. However, the fabrication of miniaturised and micro-patterned open-air soft actuators has remained challenging. In this study, we demonstrate the microfabrication of trilayer electrochemical actuators through aerosol jet printing, a rapid prototyping method with 10 μm lateral resolution. A fully printed 1 mm × 5 mm × 12.2 μm ultrathin PEDOT:PSS/Nafion/PEDOT:PSS actuator is successfully actuated in air under voltages from ±0.1 V to ±0.8 V, giving deflection angles proportional to the applied voltage, and reaching a peak-to-peak deflection of 0.25 rad (14 degrees) under a ±0.8 V 0.1 Hz square wave. The thinness of this AJP actuator reduces the proton transport length and flexural rigidity, hence causing relatively fast response and large deflection under low voltages. Next, we fully printed an actuator with two individually controlled submillimetre segments and demonstrated its multimodal actuation. The convenience, versatility, rapidity, and low cost of our microfabrication strategy promises future developments in integrating arrays of intricately-patterned individually-controlled soft microactuators on compact stretchable electronic circuits.