The rational design of ultrathin Pt-based bimetallic nanostructures with controlled morphology and composition is essential for advancing electrocatalysts for the oxygen reduction reaction (ORR). Alloying Pt with secondary transition metals such as Fe, Co, and Ni is a widely adopted strategy to tune surface chemistry and catalytic behavior; however, achieving controlled incorporation of these metals into ultrathin one-dimensional Pt architecture remains challenging due to disparate reduction kinetics and stringent synthesis conditions. In this work, we present a generalized, template-assisted wet-chemical approach for the synthesis of ultrathin, single-crystalline PtM (M = Fe, Ni, Co) bimetallic nanowires with diameters below 3 nm, using preformed Pt nanowires as structural templates. Stepwise thermal treatment enables controlled incorporation of secondary metals while preserving the one-dimensional morphology and crystallographic coherence of the Pt framework. Comprehensive structural and compositional characterization using X-ray diffraction (XRD), transmission electron microscopy (TEM), high-angle annular dark-field scanning TEM (HAADF-STEM), and energy-dispersive X-ray spectroscopy (EDXS) confirms the formation of high-aspect-ratio bimetallic nanowires with uniform elemental distribution. Electrochemical evaluation toward ORR in alkaline media reveals composition-dependent catalytic behavior, with PtFe nanowires exhibiting the most favorable activity among the studied catalysts. These results highlight the versatility of the template-assisted strategy for producing compositionally tunable Pt-based nanowires and provide insights into the structure–activity relationships governing their electrocatalytic performance. Schematic showing synthesis route of ultrathin PtM (M = Fe, Ni, Co) bimetallic nanowires using Pt nanowire as template.
Samantaray et al. (Sun,) studied this question.