Electrosynthesis of Mn-Fe oxide nanopetals on carbon paper as bi-functional electrocatalyst for oxygen reduction and oxygen evolution reaction

摘要

A layered binary Mn-Fe oxide as bi-functional electro-catalyst with nanopetals morphology is grown on porous carbon paper for the first time via one-step electrodeposition process. The electrocatalyst is characterized by X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive spectroscopy analysis. SEM analysis demonstrates notable morphology viz. nanopetals of the Mn-Fe oxide grown on carbon paper. The electrocatalytic activity is checked for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in alkaline medium. Rotating disk electrode (RDE) voltammetry is carried out to study the ORR kinetics, which proves that ORR process follows four-electron pathway in alkaline medium. Oxygen evolution reaction study reveals that it has higher activity for OER with a lower onset potential of 1.6 V vs RHE and higher current density of 11.5 mA/cm(2) at 2.0 V vs RHE reference electrode. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.