Multimetallic Core/Interlayer/Shell Nanostructures\nas Advanced Electrocatalysts

Abstract

The fine balance between activity\nand durability is crucial for\nthe development of high performance electrocatalysts. The importance\nof atomic structure and compositional gradients is a guiding principle\nin exploiting the knowledge from well-defined materials in the design\nof novel class of core–shell electrocatalysts comprising Ni\ncore, Au interlayer, and PtNi shell (Ni@Au@PtNi). This multimetallic\nsystem is found to have the optimal balance of activity and durability\ndue to the synergy between the stabilizing effect of subsurface Au\nand modified electronic structure of surface Pt through interaction\nwith subsurface Ni atoms. The electrocatalysts with Ni@Au@PtNi core-interlayer-shell\nstructure exhibit high intrinsic and mass activities as well as superior\ndurability for the oxygen reduction reaction with less than 10% activity\nloss after 10 000 potential cycles between 0.6 and 1.1 V vs\nthe reversible hydrogen electrode.