Optimization of Ni-Mo-Coated Stainless Steel as a High-Performance Cathode in Alkaline Water Electrolysis

Abstract

Due to the importance of low cost and e cient electrodes development for alkaline water electrolysis, optimization of Ni-Mo coated stainless steel is investigated in the work to use as the cathode of alkaline water electrolyser. The crystallographic structure and surface morphology and composition of the studied coatings is characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM).The electrocatalytic activity for the Hydrogen evolution reaction (HER) is evaluated using electrochemical measurement. Also, optimization of electrodeposition bath is investigated to promote the catalytic activity for HER. The results show that Nickel-Molybdenum alloy exhibits better HER activity and at -1.7 V vs. Ag/AgCl, current density of 180 mA cm − 2 is achieved. Also, the cell analysis tests revealed that using optimized electrode, at current density of 1.5 A.cm − 2 and operating temperature of 60°C, the cell operates at 1.9 V that is compatible to use for large scale industrial alkaline water electrolysis units. HighlightsCatalytic activity of Ni, Mo and Ni-Mo alloy coated stainless steel is compared in HER.Ni-Mo coated cathode is more active than Ni and Mo coatings for HER.The electrodeposition bath composition affected the catalytic activity of Ni-Mo alloy.Optimization of electrodeposition bath is led to the cathode active area and HER activity increase.

Hydrogen production by traditional and novel alkaline water electrolysis on nickel or iron based electrocatalysts

“…28 The popularity of NiFe-and NiMo-based materials being used in OER and HER electrocatalysts proves their high efficiency, which has been further evidenced by their extensive use in the reported electrolyzer-level studies, particularly in the field of hydrogen production from AWE. 29,30 By optimizing the OER and HER electrocatalysts, the cell voltage consumed during the process of OWS can be significantly decreased. However, a considerable cell voltage of around 1.8-2.0 V is still required for a normal AWE at an industrial current density of 0.3-0.5 A cm À2 .…”

“…28 The popularity of NiFe- and NiMo-based materials being used in OER and HER electrocatalysts proves their high efficiency, which has been further evidenced by their extensive use in the reported electrolyzer-level studies, particularly in the field of hydrogen production from AWE. 29,30…”