Carbon-supported Ir-Ti as a Novel Cathode Catalyst for PEFCs

Abstract

Carbon-supported Ir and Ir-Ti nanoparticle catalysts were successfully synthesized using IrCl3 and TiCl3 as the Ir and Ti precursors in ethylene glycol refluxing at 120oC. These nanoparticles were evaluated as cathode catalysts in proton exchange membrane fuel cell (PEMFC). The catalysts were characterized by X-ray diffraction (XRD) and high resolution transmission electron microscope (TEM). Experiments showed that the carbon-supported 40%Ir-10%Ti/C catalysts give a well dispersion with mean particle size of 2 nm. The electrochemical characterizations, performed using a rotating disk electrode by cyclic voltammetry with emphasis on the activity of the catalysts, are presented in 0.5 M H2SO4. The 40%Ir-10%Ti/C exhibits promising catalytic performance in terms of oxygen reduction reaction (ORR). High cell performance was achieved with a loading of 0.4 mg cm−2 40%Ir-10%Ti/C catalyst, which results in a maximum a power density of 459 mW cm−2.