Patents: April 2012

摘要

A core-shell catalyst particle is produced by preparing a core particle containing a first core metal (selected from Pd, Ag, Rh, Os or Ir) which has a standard electrode potential of at least 0.6 V and a second core metal (selected from Co, Cu, Fe or Ni) with a lower electrode potential. The second core metal is eluted by adjusting the pH (2 to 4) and the potential (?2 V to 1 V) of the core particle and the shell portion is coated on the core particle by displacement plating to replace a Cu monoatomic layer deposited by underpotential deposition. The shell portion includes a metal selected from Pt, Ir and Au. The average diameter of the core particle is 4–40 nm.