Preparation of Pd−Pt Bimetallic Colloids with Controllable Core/Shell Structures

Abstract

Polymer-protected Pd−Pt bimetallic colloids in the size range 1.5−5.5 nm with controllable core/shell structures have been successfully prepared by a so-called hydrogen-sacrificial protective strategy. The obtained bimetallic colloids were characterized by transmission electron microscopy and infrared carbon monoxide (IR-CO) probe techniques. The Pd-core/Pt-shell and Pt-core/Pd-shell structures were confirmed by IR-CO probe characterization. IR-CO probe measurements were also performed on the Pd−Pt bimetallic colloids prepared by coreduction of the corresponding metal ions in the refluxing mixture of ethanol and water.