Unconventional synthesis of Cu–Au dendritic nanowires with enhanced electrochemical activity

Abstract

Cu–Au dendritic nanowires (NWs) were synthesized by heating pre-synthesized Cu NWs and Au ultrathin NWs in a THF/H₂O mixture. The obtained dendritic NWs were composed of a Cu/CuO stem and distributed by Au multi-branches throughout the whole structure. The formation of a dendritic structure was initiated from oxidation of Cu to CuO during the phase transition stage, giving an anisotropic dendritic precursor. Then a galvanic replacement reaction between Cu and Au ions created abundant anchor sites, facilitating Au branch formation via self-deformation of ultrathin Au NWs around the Cu NWs surface. The synthesized Cu–Au dendritic NWs could be potentially used as biosensors in detecting glucose for its high sensitivity and excellent performances, due to the demonstration of their enhanced electrochemical activity for oxidation of glucose.