Nafion-stabilized Ir85Se15/C catalyst for oxygen reduction reaction in proton exchange membrane fuel cells

Ir85Se15/C catalyst synthesized using Nafion as the stabilizer (Nafion-Ir85Se15/C) has been characterized by X-ray diffraction, transmission electron microscopy, electrochemical impedance spectra measurement, rotating disk electrode and single cell tests. In comparison with Ir85Se15/C catalyst prepared by a traditional polyol method, Nafion-Ir85Se15/C exhibits higher activity for oxygen reduction reaction and better single cell performance. The maximum power density of the single cell with the Nafion-Ir85Se15/C as cathode catalyst is 736 mW cm−2, which is 1.8 times as much as that with the Ir85Se15/C catalyst. Therefore, Ir85Se15/C catalyst is expected to be used as an effective cathode electrocatalyst for proton exchange membrane fuel cells by employing Nafion as the stabilizer.

► Nafion was used as the stabilizer in the synthesis process. ► The particle size of the catalyst is controllable. ► The ORR activity of the catalyst is improved. ► The maximum power density is improved to as 1.8 times that of the former.