Facile fabrication of a flexible electrode by electrodeposition of palladium on silver nanowires for ethanol oxidation

Abstract

Currently, most of the working electrodes in electrochemistry are fabricated on rigid substrates. However, flexible electrodes may play important roles in future electronics, such as wearable medical devices and fuel cells. In this study, a flexible Pd/AgNWs/PDMS electrode was generated by the electrodeposition of palladium (Pd) onto silver nanowires (AgNWs), which were drop-casted on polydimethylsiloxane (PDMS). Scanning electron microscopy (SEM) results showed that the AgNWs or the Pd coated AgNWs distributed evenly on the PDMS substrates. In addition, Pd nanoparticles were uniformly deposited on the AgNWs and the amount of the Pd nanoparticles on the AgNWs gradually increased along with the increasing deposition time. When this flexible electrode was used as the working electrode in a three-electrode system for ethanol oxidation in alkaline media (0.1 M KOH), the results showed that the electrode deposited for 25 CV cycles performed the best in 1.0 M ethanol, exhibiting large electrochemical active surface area (ECSA, 17.05 m2 g−1), more negative onset potential (−0.60 V, vs. Ag/AgCl), lower peak potential (0.56 V, vs. AgNWs), and enhanced charge transfer by electrochemical impedance spectroscopy (EIS). The new facile method for the construction of this bimetallic flexible catalytic electrode may inspire interesting applications in electrochemistry.