Fabrication of Vertex‐type‐selectively Reinforced PtCu@PtCuNi Double‐layered Nanoframes for Efficient Methanol Electrooxidation Catalysis

Abstract Herein, we report a two‐step strategy for the preparation of vertex‐type‐selectively reinforced PtCu@PtCuNi double‐layered nanoframes (DNFs). In the first step, PtCuNi heterogeneous nanocrystals (HNCs) were synthesized by a facile one‐pot solvent method. The PtCuNi HNC is composed of a Cu‐enriched concave rhombic dodecahedral core, a double‐layered nanoframe consisting of an inner vertex‐selectively‐reinforced rhombic dodecahedral PtCu nanoframe and an outer concave rhombic dodecahedral PtCuNi nanoframe, and a Ni‐enriched shell. In the second step, PtCu@PtCuNi DNFs were prepared by selectively removing the leachable components via acid treatment. Strikingly, the inner rhombic dodecahedral nanoframe contained six nanopods sticking out from its ⟨100⟩ vertices rather than ⟨111⟩ ones, and the outer concave rhombic dodecahedral nanoframe is formed by interconnecting the adjacent vertices of the inner nanoframe. The electrocatalytic test for methanol oxidation reaction showed that the as‐prepared PtCu@PtCuNi DNFs exhibited enhanced electrocatalytic activity and improved stability compared to the commercial Pt/C catalyst.