Facile One-Step Deposition of Nanosized Ni(OH)2-MoS2 Heterostructure Electrodes for Efficient Oxygen Evolution Reaction

Abstract

The growing demand for clean and sustainable energy sources relies on efficient and cost-effective electrocatalysts for the OER, a key energy conversion and storage device process. Using a vacuum kinetic spray technique nano-sized Ni (OH)2-MoS2 nanocomposites (NCs) electrocatalysts on nickel foam are fabricated from the corresponding micron powder. The modified working electrodes by Ni (OH)2-MoS2 NCs were utilized for oxygen evolution reaction (OER) at different weight ratios of MoS2 (25, 50, and 75 wt.%). The surface state of the electrode is examined using sensitive techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). SEM images showed that the microparticles were fragmented into smaller nanoscale particles. XPS spectra revealed the synergy enhancement in the Ni (OH)2-MoS2 NCs that resulted in a strong improvement in the OER activity, which hybrid NCs with 75 wt.% MoS2 exhibits the lowest overpotential of 282 mV@10 mA·cm-2 and the lowest Tafel slope of 54 mV·dec-1. Besides, the long-term OER durability is verified up to 50 h.