Graphical Abstract

Although nanostructures based on noble metal alloys are widely utilized in (electro)catalysis, their low-temperature synthesis remains an enormous challenge due to the different Nernst equilibrium potentials of metal precursors. Herein, we describe the successful synthesis of trimetallic PtRhNi alloy nanoassemblies (PtRhNi-ANAs) with tunable Pt/Rh ratios using a simple mixed cyanogel reduction method and provide a detailed characterization of their chemical composition, morphology, and structure. Additionally, the electrochemical properties of PtRhNi-ANAs are examined by cyclic voltammetry, revealing composition-dependent electrocatalytic activity in the ethanol oxidation reaction (EOR). Compared to a commercial Pt black electrocatalyst, optimized Pt3Rh1Ni2-ANAs display remarkably enhanced EOR electrocatalytic performance in alkaline media.
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