Platinum nanoparticles prepared by ion implantation exhibit high durability for fuel cell applications

Abstract

Proton exchange membrane fuel cells (PEMFCs) have attracted considerable attention as distributed power sources for automotive and residential applications. In PEMFCs, platinum (Pt) nanoparticles supported on carbon materials are used as electrocatalysts for oxygen reduction reactions. However, improved durability of the electrocatalysts is urgently required for commercialization purposes. We describe an ion implantation technique for the preparation of Pt nanoparticles with superior catalytic properties, suitable for fuel cell applications. The Pt nanoparticles were obtained by implanting a glassy carbon (GC) substrate with 100 keV Pt-ions, followed by electrochemical etching and a heat treatment. Electrochemical measurements of the Pt nanoparticles prepared by the proposed implantation technique demonstrated superior durability when compared to those prepared by the conventional magnetron sputtering method. We suggested that the defective structure of the GC substrate, caused by the Pt-ion implantation, has led to the improved electrochemical stability of the GC substrate and Pt-carbon support interactions, thereby enhancing the durability of our Pt nanoparticles.