Electrochemical energy conversion realized through Ag@Pt/rGO nano-catalyst enhancing activity of the ORR process in a PEMFC

In this study, core-shell structures of Ag@Pt nanoparticles (NPs) were dispersed upon reduced Graphene Oxide (rGO) support that contains dierent Ag:Pt mass ratios synthesized through the ultrasonic treatment method. These were applied to an Oxygen Reduction Reaction (ORR) process in a Proton Exchange Membrane Fuel Cell (PEMFC). The morphology of as-prepared catalysts was characterized through High-Resolution Transmission Electron Microscopy (HRTEM), X-Ray Diffraction (XRD), and Induced Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) analyses. The ORR activities and stabilities of catalysts were studied through electrochemical measurements of Cyclic Voltammetry (CV) and single cell tests, respectively. Results revealed that the prepared Ag@Pt/rGO catalysts possessed a core-shell nanostructure, and the one with an Ag:Pt mass ratio of 1:3 displayed the largest electrochemical surface area of 77.6 m2 g􀀀1. Moreover, this material provided the highest stability among other synthesized electrodes, containing dierent Ag:Pt mass ratios, and the obtained commercial Pt/C electrode. The maximum power density for the MEA prepared with this electrocatalyst was determined to be 55% higher than that of the commercial Pt/C, evaluated through single cell techniques. Thus, the understudied material seems to be a very promising cathode for use in PEM fuel cells.