Solid state preparation of carbon-supported Pt2Ca nanoparticles for the oxygen reduction reaction†
Abstract
Pt2Ca nanoparticles with a mean size diameter of 6 nm can be prepared by heating K2PtCl6, CaH2, carbon black and KCl at 400–500 °C. A mechanism study suggests that the formation of the Pt2Ca phase at moderate temperature is enabled by the fast ion transport via the vacancies in the KCl–CaH2 solid solution. The Pt2Ca nanoparticles exhibit high performance for the oxygen reduction reaction in acid due to optimal adsorption energy of the oxygen intermediate.