Prussian Blue Modified Reduced Graphene Oxide as Support for Pt Nanoparticles: Development of Efficient Catalysts for Oxygen Electroreduction in Acid Medium

TL;DR

This study develops and characterizes Prussian Blue-modified reduced graphene oxide supports for platinum nanoparticles, resulting in efficient catalysts that reduce hydrogen peroxide formation during oxygen reduction in acid media.

Contribution

It introduces a novel Prussian Blue-modified rGO support for platinum catalysts, enhancing oxygen reduction efficiency and decreasing peroxide intermediates in acidic solutions.

Findings

Prussian Blue modification does not alter oxygen reduction potential.

Hydrogen peroxide intermediates are significantly reduced.

The catalyst operates via a bifunctional mechanism involving Pt and PB-modified support.

Abstract

Pt electrocatalytic nanoparticles were deposited onto hybrid carriers composed of reduced graphene oxide (rGO)-transition metal hexacyanoferrate (Prussian Blue-PB) and the resulting system's electrochemical activity was investigated during oxygen reduction reaction in acidic solution. The Prussian Blue -utilizing and Pt nanoparticle-containing materials were characterized using transmission electron microscopy, X-ray diffraction and electrochemical diagnostic techniques such as cyclic voltammetry and rotating ring-disk voltammetry. Application of rGO carriers modified with Prussian Blue as matrices (supports) for Pt catalytic centers does not change practically the potential of electroreduction of oxygen in 0.5 mol dm-3 H2SO4 (under rotating disk voltammetric conditions) relative to the behavior of the analogous PB-free system. What is even more important that, due to the presence of the polynuclear cyanoferrate modifier, the amounts of the undesirable hydrogen peroxide intermediate are significantly decreased (at ring in the rotating ring-disk voltammetry). The results are consistent with the bifunctional mechanism in which oxygen reduction is initiated at Pt centers and the hydrogen peroxide intermediate is reductively decomposed at reactive PB-modified rGO supports.