Increasing the breakdown strength of dielectric actuators by using Cu/CuxO/silicone dielectric elastomers

Dielectric elastomer actuators (DEAs) have been receiving extensive attention due to their unparalleled combination of high energy density, high efficiency, softness, silent operation, and muscle-like performance, which are favorable for soft robotics. However, DEAs encounter safety problems due to dielectric breakdown at high electric fields. In this work, we fabricate DEAs by using Cu/CuxO/PDMS (polydimethylsiloxane) composites as dielectric elastomers. Due to the presence of a CuxO layer as the insulating layer, which blocks the formation of conductive networks and reduces the dielectric loss, the Cu/CuxO/PDMS film with 15 wt% content of Cu/CuxO exhibited a significantly higher breakdown strength (29.17 V μm−1 as compared to 12.50 V μm−1 for the Cu/PDMS film). Such results are helpful for further fabrication of DEAs with improved safety.