Electrocatalytic Properties of Ni-Based Alloys Toward Hydrogen Evolution Reaction in Acid Media

Abstract

The electrocatalytic performance toward the hydrogen evolution reaction ͑HER͒ of a series of Ni-based alloys prepared by electroless deposition was studied by means of linear polarization, cyclic voltammetry, and potential step techniques. Ni-W-P and Ni-Mo-P alloy electrodes exhibit good electrocatalytic activity toward HERs, with some Ni-Mo-P alloys approaching the performance of Pt foils. The electrocatalytic activity of Ni-based alloys decreases with increasing P content but increases with increasing content of W or Mo. The experimental results can be interpreted in terms of a pronounced synergy between Ni, which has internally paired d electrons, and W or Mo, which have empty or half-filled d orbitals and therefore, bind hydrogen atoms strongly. The absorption of hydrogen in these alloys is also found to have an important effect on their activity. Electrodes with higher activity are capable to incorporate larger amounts of hydrogen during cathodic charging.

Catalytic Activity of Nickel Alloys in Anodic Oxidation of the Hypophosphite Ion as a Function of Their Composition

“…As follows from the data of XRD analyses we performed, which are confirmed by [2], the insertion of molybdenum as a third component in the Ni-P coatings makes no impact on the surface morphology. Thus, we can estimate the contribution made by the electronic constituent to the catalytic activity.…”

“…As follows from the reflection smearing, the coatings turn amorphous with increasing sodium hypophosphite concentration. According to [2], no grain boundaries, which are structural defects with a higher electrocatalytic activity in the reaction of anodic oxidation of the hypophosphite ion, were discovered in nickel alloys enriched by phosphorus. This fact may also reduce the catalytic activity of the surface with increasing phosphorus content.…”

“…Of late there appeared works devoted to using the alloys as electrode materials, for these are stable chemically and exhibit catalytic properties in reactions of hydrogen [1][2][3][4] and oxygen [5] evolution and oxidation of diverse organic compounds [6]. Nickel and its alloys also catalyze anodic oxidation of the hypophosphite ion, which reaction is the limiting stage of the so-called electroless deposition of many metals, including nickel itself.…”

Hydrogen Evolution Reaction Property of Molybdenum Disulfide/Nickel Phosphide Hybrids in Alkaline Solution

“…To facilitate HER application, it is urgent to develop low-cost alternatives with Earth-abundant and cost-effective features to replace the noble metals [17,18]. Thus, various non-noble materials including transition metal sulfides [19], selenides [20], oxides [21], carbides [22], and nitrides [23],…”

Ternary alloy nanocatalysts for hydrogen evolution reaction

“…Although Ni use in acidic media is restricted due to corrosion, it can be used in the alkaline medium as the process of corrosion is insignificant. It has been well established that water splitting in the alkaline medium for the production of pure hydrogen has an advantage due to being environmentally benign, having low cost and being unaffected by poisoning [1,2], which is one of the greatest challenges associated with proton exchange membranes in water electrolysis [3][4][5][6]. Taking these points into consideration, we have focussed on synthesizing nanostructured ternary alloys; based on Cu-Fe-Ni alloys which includes Ni as one of the constituent metal and alloyed with two metals, one with weak M-H binding energy (Fe) and the other having strong M-H binding energy (Cu) as observed from the volcano curve [7,8].…”