A supramolecular electrode with high self-healing efficiency at room temperature, recyclability and durability for dielectric elastomer generators

Abstract

To achieve dielectric elastomer generators (DEGs) with excellent energy harvesting performance and long life, electrode materials with high compliance, high electrical conductivity (EC), high stability of EC under high strain, and high durability are key. Nevertheless, the compliance of previously reported electrodes for DEGs still needs to be improved, and they cannot be repaired at room temperature after being damaged, inducing the trouble of disassembling the DEG device. In this study, a highly conductive supermolecule-based electrode material for DEGs was designed and prepared by synthesizing a polyborosiloxane supermolecule network (PBS-SN) matrix with multiple dynamic bonds followed by introduction of highly conductive carbon black (CB) and carbon grease (CG) into the PBS-SN matrix. Benefiting from the multiple dynamic bonds of the PBS-SN matrix and the introduction of appropriate content of a silicone oligomer (SO) with high chain mobility and plasticizing effect, the as-prepared CB/CG/PBS-SN electrode exhibits a high elongation at break (>1000%), high compliance, high self-healing efficiency of EC at room temperature (93% for 3 h), good recyclability (at least five times without performance reduction) and high durability (up to 10 000 cycles). Compared with a DEG using the commonly used CG electrode, the DEG using the CB/CG/PBS-SN electrode exhibits higher energy density, which is 60.9% higher than that of the former, and much higher than that reported in many previous studies. The excellent room temperature self-healing ability of the electrode can help the in situ repair of the DEG device, reducing the trouble of disassembling the device and improving the convenience of usage.