Abstract: The present invention is directed to hollow catalyst particles comprising a layered shell structure and to a method of their manufacture. The catalyst particles have the general formula Hcore/PMinner shell/IL/PMouter shell in which Hcore is the hollow core, PMinner shell is a precious metal forming the innermost layer of the shell, IL is an intermediate layer comprising a base metal/precious metal alloy, and PMouter shell is a precious metal forming the outermost layer of the shell. The precious metal is selected from Pt, Ir and Pd and mixtures or alloys thereof, and IL is an intermediate layer comprising a base metal/precious metal alloy wherein the concentration of the base metal changes from the periphery of the hollow core to the outer surface of the intermediate layer. The base metal is selected from Co, Ni, and Cu and mixtures thereof.

Abstract: The present invention is directed to catalyst particles comprising a layered core-shell-shell structure and to a method of their manufacture. The catalyst particles have the general formula BM/IL/PM in which BM is a base metal core (selected from Co, Ni or Cu), PM is a precious metal outer shell (selected from Pt, Ir or Pd) and IL is an intermediate layer comprising a base metal/precious metal alloy with a concentration gradient of base metal to the outside PM layer. The particles of the present invention comprise a core-shell-shell structure and a substantially continuous precious metal shell layer. They find use in various catalytic applications, for example in gas-phase catalysis, in electrocatalysts for fuel cells, in catalytic converters for automobiles and in electronic or medical applications.

Abstract: The present invention is directed to hollow catalyst particles comprising a layered shell structure and to a method of their manufacture. The catalyst particles have the general formula Hcore/PMinner shell/IL/PMouter shell in which Hcore is the hollow core, PMinner shell is a precious metal forming the innermost layer of the shell, IL is an intermediate layer comprising a base metal/precious metal alloy, and PMouter shell is a precious metal forming the outermost layer of the shell. The precious metal is selected from Pt, Ir and Pd and mixtures or alloys thereof, and IL is an intermediate layer comprising a base metal/precious metal alloy wherein the concentration of the base metal changes from the periphery of the hollow core to the outer surface of the intermediate layer. The base metal is selected from Co, Ni, and Cu and mixtures thereof.

Abstract: The present invention is directed to catalyst particles comprising a layered core-shell-shell structure and to a method of their manufacture. The catalyst particles have the general formula BM/IL/PM in which BM is a base metal core (selected from Co, Ni or Cu), PM is a precious metal outer shell (selected from Pt, Ir or Pd) and IL is an intermediate layer comprising a base metal/precious metal alloy with a concentration gradient of base metal to the outside PM layer. The particles of the present invention comprise a core-shell-shell structure and a substantially continuous precious metal shell layer. They find use in various catalytic applications, for example in gas-phase catalysis, in electrocatalysts for fuel cells, in catalytic converters for automobiles and in electronic or medical applications.

Abstract: The present invention is directed to a process for manufacture of base metal nano-particles using precious metal seed particles. The process comprises the steps of mixing at least one base metal precursor and at least one precious metal precursor in one or more polyol solvents, reacting the mixture at a temperature in the range of 110 to 150° C. to form precious metal seed particles (STEP A) and reacting the mixture at a temperature in the range of 180 to 220° C. to form the final metal particles (STEP B). Base metal particles of Co, Ni and Cu containing 100 to 10000 ppm of precious metals Ru, Pd, Pt or Ir are obtained. The resulting metal nano-particles with medium diameters of 20 to 200 nm are useful for electronic and catalytic applications and can be used as core materials for the manufacture core/shell type catalysts.