One –step synthesis of PdCo alloy nanoparticles decorated on reduced grahene oxide as an Electro-catalyst for Oxygen Reduction Reaction in Passive Direct Methanol Fuel Cells

Abstract

We report a Pd-Co (3:1)/graphene oxide (Pd3Co /GO) catalyst through a one-step strategy. GO is synthesized from graphite electrodes using ionic liquid-assisted electrochemical exfoliation. Controllable GO-supported Pd3Co electrocatalystis then was reduced by ethylene glycol as a stabilizing agent to prepare highly dispersed PdCo nanoparticles on carbon graphene oxide to be used as oxygen reduction reaction in passive direct methanol fuel cell (DEFC) catalysts. The performance of these electrodes in the ORR was measured with cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), chronoamperometry (CA), inductive coupled plasma (ICP), X-ray diffraction (XRD) and scanning electron microscopy coupled to energy dispersive X-ray (SEM–EDX). Since the Pd3Co/GO alloy electrocatalysts are inactive for the adsorption and oxidation of methanol, it can act as a methanol-tolerant ORR catalyst in a direct methanol fuel cell (DMFC). A membrane-electrode assembly (MEA) has been prepared by employing of the Pd3Co/GO as a cathode for passive direct methanol fuel cell and characterized by polarization curves and impedance diagrams. A better performance was obtained for the cell using Pd3Co/RGO (3.56 mW cm–2) compared to Pd/RGO (1.75 mW cm–2) and Pt/C-Electrochem (1.9 mW cm–2) as cathode in the DMFC.