Morphology-controlled synthesis of ternary Pt-Pd-Cu alloy nanoparticles for efficient electrocatalytic oxygen reduction reactions

In the present work, we have accomplished morphology-controlled synthesis of ternary Pt-Pd-Cu alloy nanoparticles, particularly for efficient electrocatalytic oxygen reduction reactions. By controlling over the degree of galvanic displacement at room temperature, we selectively introduced porous and hollow architectures into Pt-decorated Pd-Cu alloy nanoparticles. Porous morphology was accompanied with partially facilitated Pt substitution reaction while hollow shape was exclusively achieved when the galvanic reaction was coupled with additional pre-treatment process which could eventually make the following displacement reaction more facile. Not only the both porous and hollow Pt@PdCu/C catalysts exhibited enhanced ORR performances compared to commercial Pt/C, but also they displayed outstanding durability. In addition, we investigated the alloying effects between Pt and Pd-Cu composite and the presumable influences of lattice strain through preliminary theoretical calculation to account for the enhanced ORR efficiency and durability of the present catalysts.