Facile synthesis of nearly monodisperse AgCu alloy nanoparticles with synergistic effect against oxidation and electromigration

Bimetallic nanoparticles (NPs) have attracted a great deal of attention due to the synergistic interaction between metal components. In this work, the thermal process in which the reducing agent is not expensive or hazardous as those in traditional methods was employed to prepare alloy Ag-Cu NPs. The molar ratio between Ag and Cu was varied from 1:9 to 9:1. Nearly monodisperse NPs with alloy structure were characterized by X-ray diffraction and high-resolution transmission electron microscopy with energy dispersive spectroscopy In comparison with monometallic Ag and Cu NPs, the alloyed Ag-Cu NPs showed better monodispersity, especially when the ratio between Ag and Cu was 1:1. Moreover, the alloyed Ag-Cu NPs exhibited enhanced resistance to electromigration and oxidation, the respective problem of pure Ag and Cu. The alloyed Ag-Cu NPs also exhibited improved properties than a mixture of Ag-Cu NPs. This study should serve as the foundation for exploring high performance alloyed bimetallic NPs.