Demonstration of Synergistic Catalysis in Au@Ni Bimetallic Core–Shell Nanostructures

Abstract

Core–shell bimetallic nanoparticles comprised of gold core and varying nickel shell have been synthesized, and their synergistic effect in catalysis is explored through catalytic hydrogenation of p-nitrophenol and p-nitrothiophenol. A clear evidence for synergism in Au@Ni core–shell nanoparticles having an ultrathin Ni shell (1–2 nm) around a Au core (6–10 nm) resulting in enhanced catalytic activity is observed. The rates observed from a thin nickel shell are higher than monometallic Au or Ni nanoparticles of similar size or with a thicker Ni shell of 6–8 nm.