Glassy carbon electrode modified by Pd-Cu bimetallic nano-dendrites film decorated on the reduced graphene oxide using galvanic replacement as a low-cost anode in methanol fuel cells

Glassy carbon electrode (GCE) modified by reduced graphene oxide Cu-Pd nano-dendrimer (Pd-CuNDs-RGO/GCE) was prepared using electro-deposition and spontaneous displacement methods. Graphene oxide was put on the surface of GCE by drop-casting, then a thin film of reduced graphene oxide (RGO) was formed by electro-reduction at similar to 0.9 V. The copper nano-dendrimers (CuNDs) were electro-plated on RGO/GCE surface. Finally, Pd-CuNDs-RGO/GCE was prepared by the spontaneous replacement of CuNDs with palladium nanoparticles (PdNPs) in a dilute solution of palladium. The electrode surface was characterized using field-emission scanning electron microscopy (FESEM), X-ray energy diffraction (EDX) spectroscopy, and electrochemical techniques. The electrochemical behavior of the modified electrode in the oxidation of alkaline solution of methanol was investigated. The experimental conditions affecting the performance of the modified electrode in the methanol oxidation were studied and optimized. Finally, the proposed electrode has the onset potential of similar to 0.5 V and the ratio of i(f)/i(b) equal to 2.2, which confirms the high catalytic activity. The electrode has appropriate stability and shows about 86% of initial activity after 100 times testing. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.