Highly active carbon-supported Pt nanoparticles modified and dealloyed with Co for the oxygen reduction reaction

Highly active carbon-supported Pt modified with transition metal Co catalysts are synthesized by an ethylene glycol (EG) reduction method as cathode electro-catalyst for proton exchange membrane fuel cell (PEMFC) applications. Synthesis conditions, such as precursor, dealloying and heat treatment are investigated to obtain the PtCo/C catalyst with the optimum performance. The active component particles are uniformly dispersed on Vulcan XC-72 support with a narrow particle size distribution centered around 2–4 nm. Energy dispersive X-ray spectroscopy (EDX) results indicate that the catalyst sample contains negligible Co contents with the addition of HCl. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) reveal that the PtCo/C electro-catalyst with cobalt (II) acetate tetrahydrate as precursor shows better performance than commercial Pt/C, for which electrochemical surface area and oxygen reduction reaction (ORR) performance of mass activity are as high as 54.25 m2 gPt−1 and 0.089 A mgPt−1, respectively. Membrane electrode assemblies (MEAs) prepared with all as-synthesized electro-catalyst samples are tested under different temperatures and relative humidity conditions. The PtCo/C electro-catalyst synthesized with cobalt (II) acetate tetrahydrate as precursor also exhibits highest MEA power density. Herein, the as-synthesized PtCo/C is considered to be promising cathode electro-catalyst to improve the utilization of platinum in PEMFC applications. •The carbon-supported Pt modified with Co synthesized via an ethylene glycol method.•Effect of different synthesis conditions investigated.•PtCo/C demonstrates superior ORR activity and cell performance.•Dealloying treatment is highly effective for improving catalyst performance.