Fabrication of Trimetallic Pt−Pd−Co Porous Nanostructures on Reduced Graphene Oxide by Galvanic Replacement: Application to Electrocatalytic Oxidation of Ethylene Glycol

Abstract

In present work, reduced graphene oxide nanosheets (rGO) decorated with trimetallic three‐dimensional (3D) Pt−Pd−Co porous nanostructures was fabricated on glassy carbon electrode (Pt−Pd−Co/rGO/GCE). First, GO suspension was drop‐casted on the electrode surface, then GO film reduction was carried out by cycling the potential in negative direction to form the rGO film modified GCE (rGO/GCE). Then, electrodeposition of the cobalt nanoparticles (CoNPs) as sacrificial seeds was performed onto the rGO/GCE by using cyclic voltammetry. Afterward, Pt−Pd−Co 3D porous nanostructures fabrication occurs through galvanic replacement (GR) method based on a spontaneous redox process between PtCl2, PdCl2, and CoNPs. The morphology and structure of the Pt−Pd−Co/rGO porous nanostructure film was characterized by scanning electron microscopy, energy dispersive spectroscopy and X‐ray diffraction method. The performance of the prepared electrode was investigated by various electrochemical methods including, cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic activity of the as‐prepared modified electrode with high surface areas was evaluated in anodic oxidation of ethylene glycol. The study on electrocatalytic performances revealed that, in comparison to various metal combinations in modified electrodes, trimetallic Pt−Pd−Co/rGO/GCE exhibit a lower onset potential, significantly higher peak current density, high durability and stability for the anodic oxidation of ethylene glycol. The excellent performances are attributed to the rGO as catalysts support and resulting synergistic effects of the trimetallic and appropriate characteristics of the resulted 3D porous nanostructures. Moreover, the influence of various concentrations of ethylene glycol, the potential scan rate and switching potential on the electrode reaction, in addition, long‐term stability have been studied by chronoamperometric and cyclic voltammetric methods.

Visible-Light-Mediated Electrocatalytic Activity in Reduced Graphene Oxide-Supported Bismuth Ferrite

“…Photoelectrochemical (PEC) water splitting, utilizing a semiconductor nanoparticle as the catalyst to produce hydrogen and oxygen, has attracted considerable attention over the past few decades. − Hydrogen generation from water splitting has the following advantages: (1) reasonable solar-to-hydrogen (STH) efficiency; (2) low processing cost; and (3) the ability to achieve separate hydrogen and oxygen evolution during the reaction. Photocatalysts facilitate the water-splitting reaction through the formation of an electron (e – ) and hole (h + ) pair under solar light irradiation, which oxidizes water on the surface of the photocatalyst unless they recombine giving no net chemical reaction.…”

Nanocomposite with Promoted Electrocatalytic Behavior Based on Bimetallic Pd–Ni Nanoparticles, Manganese Dioxide, and Reduced Graphene Oxide for Efficient Electrooxidation of Ethanol

“…21 In this regard, reduced graphene oxide (rGO) is considered as a good catalyst support due to its intrinsic properties like high electrical conductivity, high surface area, ease of preparation, and low cost. 22 Also, a graphitized two-dimensional plane structure with surface oxygen-containing functional groups on both basal planes and the edges of rGO provides anchoring places to facilitate distribution and stability of the surface immobilized catalysts. 23 Moreover, rGO plays a vital role in decreasing catalyst poisoning effects by removing the CO-like intermediate species.…”