Preparation and performance of soft actuator based on IPMC with silver electrodes

The surface electrodes of traditional ionic polymer-metal composites (IPMC) are made of platinum. To reduce the production cost, nonprecious metals such as silver is proposed. A new approach of electroless silver plating based on chemical deposition method is adopted, getting two types of IPMCs, Pt-Ag IPMC, and Ag-Ag IPMC. The microscopic analysis, driving abilities tests, and their surface-electrode resistance analysis show that Ag and Pt particles penetrate inside Nafion membrane with gradient distribution throughout the membrane. The maximum electro-active bending deformation angles of the specimens, which are obtained under the same specimen dimension and constrains, are about 60 degrees for Pt-Pt IPMC and Pt-Ag IPMC and 90 degrees for the Ag-Ag IPMC, respectively, corresponding to the driving voltage of 3 V, 4 V, and 1.5 V. The surface-electrode resistance of Ag-Ag IPMC is the lowest and the most stable, which shows that the proposed approach is valid. The experiments show that the IPMC technology based on the silver electrode is feasible.