Facile synthesis of Pd@Pt octahedra supported on carbon for electrocatalytic applications

Due to the scarcity of Pt, it is highly desirable to construct core‐shell structures with ultrathin Pt shells while maintaining their high electrocatalytic activities. However, it is necessary to preferentially synthesize a core with a specific structure before further formation of core‐shell catalysts with specific morphologies. This prerequisite greatly increases the complexity of the synthesis process. This article describes a synthetic method of core‐shell Pd@Pt octahedra catalysts from Pd nanocubes, truncated nanocubes or truncated octahedra. The formation of octahedral core‐shell structures involves two key factors: (1) the oxidative etching process of Pd atoms at the corner sites; (2) the different reduction rates between Pt and Pd precursors. This mechanism can be extended to synthesize carbon‐supported sub‐8 nm Pd@Pt octahedra from commercial Pd/C catalysts. The derived carbon‐supported Pd@Pt octahedra catalysts performed comparable activity and durability for methanol oxidation reaction with state‐of‐art PtRu/C catalysts. This synthetic method provides an innovative path for large‐scale production of well‐controlled catalysts.