Facile Design of Conductive Ag-PDMS Electrodes for Stretchable Electrodes

Recent technological progress towards the application of wearable electronic devices has prompted the development of flexible electrodes. To date, various technical approaches to improve the mechanical and electrical reliability of flexible electrodes have been reported; however, the transition from lab-scale processing to industrialization is still limited by complex processing steps involved in their preparation. Simple engineering steps are introduced to prepare flexible electrodes fabricated from silver-polydimethylsiloxane (Ag-PDMS) composites for wearable device applications. The electrical properties of the electrodes were investigated under stretching and bending conditions. Also, the effect of different Ag contents in the electrodes on electrical properties was investigated. As increasing the Ag content above 300 wt.%, Ag-PDMS electrodes exhibit electrical conductivity, which is closely related to the percolation threshold for the formation of a 3-D network of Ag in the PDMS matrix. Further increase of Ag content up to 450 wt.% resulted in electrical conductivity about 1000 S/cm, corresponding to an electrical resistivity of 1 mΩ cm. Furthermore, we investigated the electrical resistivity changes when repetitive stretching and bending deformation was applied. Based on the conceptual demonstration of a light-emitting diode circuit using Ag-PDMS electrodes, a simple printable electrode fabrication method can be applied to various stretchable electronic devices.