Flexible Ag@Au core-shell nanowires electrode fabrication with controllable nanogold size and thickness on silver nanowires/PDMS substrate toward enhanced ethanol electrooxidation

The synthesis of gold nanowires (AuNWs) is challenging due to difficulties in obtaining AuNWs of variable diameters and lengths. In this study, an effective approach to fabricating AuNWs with controllable lengths and diameters was developed on a flexible silver nanowires (AgNWs)/polydimethylsiloxane (PDMS) substrate. Gold nanoparticles were uniformly electrodeposited onto the flexible AgNWs/PDMS to form bimetallic Ag@Au core-shell NWs/PDMS. The results showed that the diameters and the lengths of the Ag@Au NWs were easily finetuned. The flexible Ag@Au NWs/PDMS electrode exhibited excellent mechanical, electrical, and electrochemical properties. In ethanol oxidation reaction (EOR), the Ag@Au NWs/PDMS achieved a peak current density of 28541.55 mu A cm(-2) (10 times higher than that of a commercial Au electrode) and 63.39% retaining activity in a stability test by chronoamperometry (over 2 times stable than values in literature). Finally, EOR and chromium (VI) determination by the Ag@Au NWs/PDMS in flexible integrated electrodes were performed to showcase the versatile feasibilities of this new material.