Green and facile synthesis of cerium doped Ni3Fe electrocatalyst for efficient oxygen evolution reaction

Abstract

Electrochemical water splitting is the most promising pathway to produce high-purity hydrogen to alleviate global energy crisis. This reaction demands inexpensive, efficient and robust electrocatalyst for its commercial use. Herein, we demonstrate an effective, facile and scalable method for the synthesis of cerium doped Ni₃Fe nanostructures as an electrocatalyst for oxygen evolution reaction (OER) by following simple chemical bath deposition route. The different molar ratios (3, 6 and 12 mM) of cerium in the chemical bath were used to study its effect on the structural and the electrochemical properties of the Ni₃Fe nanostructured films. Doping of cerium contents induced variations in the morphology of deposited Ni₃Fe nanostructures. The optimized electrocatalyst Ni₃Fe/Ce-6 yielded high surface area catalyst nanosheets uniformly deposited on three-dimensional conductive scaffold to ensure increase in the exposure of doped Ni₃Fe catalytic sites with high electrical conductivity. As a result, this earth-abundant electrocatalyst affords high OER performance with a small overpotential of 310 mV versus reversible hydrogen electrode (RHE) at 10 mA cm^-2 and retains good stability up to ~ 10 h in alkaline electrolyte. This scalable strategy has great potential in future advancement of efficient and low-cost electrocatalysts for their large-scale application in energy conversion systems.

KEY WORDS: Oxygen evolution, Electrocatalyst, Ni₃Fe nanostructures, Cerium, Alkaline electrolyte

Bull. Chem. Soc. Ethiop. 2020, 34(2), 353-363

DOI: https://dx.doi.org/10.4314/bcse.v34i2.12