Modifying the 316L stainless steel surface by an electrodeposition technique: towards high-performance electrodes for alkaline water electrolysis

Abstract

A simple electrodeposition process has been used to modify the stainless steel surface with nickel phosphide nanoparticles for use as a highly active, stable, and inexpensive OER/HER bifunctional electrocatalyst in alkaline overall water splitting.

Recycled Steel from Waste Dead Nickel–Metal Hydride (Ni–MH) Batteries as Efficient Bifunctional Electrodes for Water Splitting: Ideal Way from Waste to Energy

“…To confirm the similarity in kinetics between individual OER/HER electrodes and the two-electrode electrolyzer system, the theoretical overall voltage V cell values at current density J cell = 10 and 100 mA cm –2 for the Act-SSM||1 M KOH||SSM system were also evaluated according to eq V normalc normale normall normall = 1.23 + η normalO normalE normalR + η normalH normalE normalR + ( R c e l l × J c e l l ) where η OER and η HER are the calculated overpotential values from LSV for anodic and cathodic half-cell reactions, respectively, using 3-electrode setups; R cell is the solution resistance of the Act-SM||1 M KOH||SM system, which was calculated from the Nyquist plot using EIS. The calculated potential values at current densities of 10 and 100 mA cm –2 are ∼1.77 and ∼1.91 V, respectively, which were almost similar to the experimental potential values calculated from the I – V curve (1.78 and 1.92 V at current densities of 10 and 100 mA cm –2 , respectively) for the 2-electrode Act-SM||1 M KOH||SM system.…”

“…The changes observed at the anodic side are due to the oxidation of Ni and the formation of NiOOH, as has been reported by other groups as well. 31 The XRD pattern of the anode material, i.e., Act-SM used in the Act-SM||1 M KOH ||SM system (Figure 8(a)), shows no change before and after electrolysis, suggesting the stability of electrodes during electrolysis. It must be mentioned that various oxides such as Ni(OH) 2 , NiOOH, Fe 3 O 4 , Fe 2 O 3 , and FeOOH may be present on the surface of the anode in a post-XRD pattern.…”

“…Different approaches such as anodization of the SS alloy at a high current density under harsh alkaline environment, 31 hydrothermal treatment, 20 activation of the SS surface by exposure to hazardous Cl 2 gas, 32 and addition of heteroatoms such as N, P, and S by hydrothermal treatment have been used to activate the SS surface to make it more active toward the water electrolysis process. 31 These surface modification approaches used extremely corrosive chemicals, acids, and metal salts, which limits their application for mass production and also makes it an uneconomical and environmentally unfavorable process. There are a few other reports in which researchers used commercially available untreated SS for OER and HER reactions, 19 but the intrinsic property deficiencies in their performance forced us to investigate other categories of steel as electrocatalysts.…”

“…Various reports have been published in the last few decades using SS as electrocatalysts that show significant results for both HER and OER, but the other three categories (CS, SA, and TS) have rarely been studied. − These articles focus on the use of commercially available SS, such as Austenitic SS (316, 316, 304, and 302 L), Ferritic SS 434 and 434 L, and mild steel S235, all of which (except the latter one) contain a certain percentage of chromium, which is not suitable for electrocatalysis in alkaline conditions (detailed compositions of these materials are given in Table S2). Different approaches such as anodization of the SS alloy at a high current density under harsh alkaline environment, hydrothermal treatment, activation of the SS surface by exposure to hazardous Cl 2 gas, and addition of heteroatoms such as N, P, and S by hydrothermal treatment have been used to activate the SS surface to make it more active toward the water electrolysis process . These surface modification approaches used extremely corrosive chemicals, acids, and metal salts, which limits their application for mass production and also makes it an uneconomical and environmentally unfavorable process.…”

Dual Modification of Stainless Steel by Small Molecule Oxalic Acid for Oxygen Evolution Reaction

“…Based on this study, they further nitrided the etched samples at high temperatures to obtain products with better activity. Finally, the in situ growth of suitable active substances on the SS, which is used as a substrate, is also one of the effective modification strategies. , …”