This work reports a general wet-chemistry method to produce Au–Cu–X (X = Pt, Pd, and Ag) trimetallic nanorods using galvanic replacement reaction with Au–Cu nanorods as the templates.

A generalized synthesis is developed for a series of metal–chalcogenide nanorods using Ag nanocrystals as seeds. The Ag based CdS nanorods without sulfurization of the Ag seeds showed improved photocatalytic properties.

Development of trimetallic nanoparticles can potentially broaden the optical window for plasmonic applications, but can also offer new photocatalysts for organic synthesis. The optical and catalytic properties can be tuned by the ratio between different components and how they are distributed in the nanoparticles, in addition to their size and shape. This work reports a seed‐mediated coreduction method for the fabrication of Au‐Cu‐Ag nanorods in oil phase. The composition and morphology of trimetallic Au‐Cu‐Ag nanostructures can be controlled by adjusting the injection temperature and the concentration of silver precursor. An additional peak (around 395 nm) is observed in extinction spectrum of trimetallic Au‐Cu‐Ag nanorods compared to that of bimetallic Au‐Cu nanorods, caused by the segregated silver composition in the trimetallic nanorods. The reported synthesis can be used to develop a wide range of trimetallic nanostructures with tunable optical properties and functionality.