Electrocatalytic Water Splitting Using Stainless Steel Electrodes

Electrocatalytic water splitting employs paired half-reactions—the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER)—to convert water into molecular oxygen and hydrogen. Stainless steel electrodes, notably grades 304 and 316, offer cost-effective substrates rich in iron, nickel and chromium. Surface activation strategies, such as potential cycling or alkaline treatment, promote selective leaching of iron and chromium, leading to the formation of nickel- and iron-rich oxyhydroxide layers that serve as active OER sites. These modified surfaces exhibit reduced overpotentials, enhanced current densities and extended operational stability under industrial conditions. The adaptability of stainless steel, combined with scalable activation protocols, positions it as a promising alternative to noble-metal-based anodes in commercial alkaline water electrolysers, advancing sustainable hydrogen production at scale.

Research from Nature Portfolio

Recent studies have employed combinatorial synthesis of Ni–Fe–Cr mixed oxides to elucidate the electronic factors that underpin high OER activity. Variation of Cr content on stainless steel-derived oxide layers was correlated with shifts in FeIII coordination, revealing that increased octahedral FeIII populations coincide with elevated catalytic currents. Soft X-ray absorption and automated electrochemical screening demonstrated that tailored Ni, Fe and Cr ratios optimise the electronic structure of surface oxides, translating to lower overpotentials and improved reaction kinetics. This high-throughput approach furnishes design principles for next-generation stainless steel electrode modifications.

Electrocatalytic Water Splitting Using Stainless Steel Electrodes publication trend

The graph below shows the total number of articles in electrocatalytic water splitting using stainless steel electrodes across all publications each year (not limited to Nature Index journals).

Technical terms

Overpotential: The extra potential beyond the thermodynamic requirement needed to drive an electrochemical reaction at a given rate.

Oxygen Evolution Reaction (OER): The anodic half-reaction in water splitting that generates oxygen, protons and electrons.

Hydrogen Evolution Reaction (HER): The cathodic half-reaction in water splitting that produces hydrogen gas from protons and electrons.

Electrocatalyst: A material that increases the rate of an electrochemical reaction at an electrode surface by lowering activation energy.

Electrochemical active surface area (ECSA): The surface area of an electrode that is accessible for electrochemical reactions, often larger than its geometric area.

Surface activation: Electrochemical or chemical treatment that modifies an electrode’s surface composition and structure to enhance catalytic performance.

References

1. Stainless Steel Activation for Efficient Alkaline Oxygen Evolution in Advanced Electrolyzers. Advanced Materials (2024).
2. Stainless steel made to rust: a robust water-splitting catalyst with benchmark characteristics. Energy & Environmental Science (2015).
3. Correlating Oxygen Evolution Catalysts Activity and Electronic Structure by a High-Throughput Investigation of Ni1-y-zFeyCrzOx. Scientific Reports (2017).
4. Electrochemical stability of stainless-steel-made anode for alkaline water electrolysis: Surface catalyst nanostructures and oxygen evolution overpotentials under applying potential cycle loading. Electrochemistry Communications (2021).
5. Tailoring the oxide surface composition of stainless steel for improved OER performance in alkaline water electrolysis. Electrochimica Acta (2022).
6. Performance of activated stainless steel and nickel-based anodes in alkaline water electrolyser. Journal of Power Sources (2023).