Fabrication of palladium and platinum nanoparticles decorated reduced graphene oxide as a highly active and stable electrocatalyst

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] In this work, we have developed new types of flexible electrodes based on chemical and electrochemical techniques by decorated reduced graphene oxide with platinum (Pt) and palladium (Pd) nanoparticles. In order to obtain reduced graphene oxide sheets, we used HI acid and EGCG as chemical reduction agents. The electrical conductivity was higher for a RGO sheet which was obtained from HI acid treatment than the samples using EGCG. The HI acid treatment exhibited a sheet with very good flexibility and a much higher tensile strength than the samples with EGCG. Chemical deposition method showed the ability of HI acid and EGCG to reduce platinum salt (Pt salt) to platinum nanoparticles (Pt NPs). All the chemical deposition samples with EGCG treatment showed a good particle distribution with a small size and less aggregation. Unlike the samples that were treated with HI acid only. One-step electrochemical deposition from different types of electrolytes was demonstrated. Morphological and structural characterizations showed that Pd NPs can be efficiently, with a very high stability and activity, decorated electrochemically on RGO from Pd NP suspension electrolyte. In addition, electrochemical deposition from (PdII complex) resulted in a very high density of Pd decorated on the surface of RGO sheet. In conclusion, this research demonstrated a variety of desirable electrocatalysis properties including excellent electrocatalytic activity, small Pd nanoparticles dispersed evenly on the surface of the electrode, and very high stability with exceptional flexibility.