Low-Alkalinity Water Electrolysis: New Membrane Boosts Efficiency

A KOH-based alkaline water electrolysis system that produces green hydrogen and oxygen using renewable electricity.in the LA-ISMWE system developed in this study, the ion-solvating membrane (ISM) separates the anode and cathode, enabling stable operation under low-alkalinity conditions. Credit: Korea Institute of Science and Technology

Seoul, January 30, 2026 – A new membrane material developed by researchers in South Korea promises to considerably lower the cost and improve the efficiency of green hydrogen production, potentially unlocking a key barrier to widespread adoption of the clean energy source.

Breaking the Efficiency-Stability-Cost Trilemma

Green hydrogen, produced using renewable energy, is gaining traction as a vital component of a enduring future, but current water electrolysis technologies struggle with high costs and performance degradation over time.

• Researchers at the Korea Institute of Science and Technology (KIST) have created a novel membrane for water electrolysis.
• The membrane operates stably and exhibits higher conductivity under low alkalinity compared to existing systems.
• This innovation could reduce electricity consumption and maintenance costs, making green hydrogen more economically viable.
• The technology is expected to bolster Korea’s competitiveness in the global green hydrogen market.

the research, published in the journal Nature Energy, details a membrane designed to overcome the limitations of conventional alkaline water electrolysis. Long-term operation of existing systems frequently enough leads to performance decline and increased maintenance,hindering commercialization.

The team, led by Dr. Dirk Henkensmeier at KIST’s Hydrogen and Fuel Cell Research Center, focused on creating a membrane that maintains high hydrogen production even in low-concentration alkaline environments. This provides a technological foundation for low-alkalinity water electrolysis, a promising pathway to more efficient and cost-effective hydrogen production.

How the New Membrane Works

The newly developed membrane avoids structural features known to cause performance degradation during prolonged use, while together ensuring stable electrolyte uptake and retention. Experimental results demonstrated the membrane’s ability to maintain electrochemical performance over extended periods, even at elevated temperatures. Crucially, it effectively separated hydrogen and oxygen, meeting essential safety standards.

(Top) Molecular structure of 50SOPBI. (Left) Higher ionic conductivity compared to anion exchange membranes. (Center) Excellent alkaline stability. (Right) Water electrolysis performance comparison among a commercial diaphragm, a commercial anion exchange membrane, and the developed ion-solvating membrane. Credit: Korea Institute of Science and Technology

More facts: Muhammad Mara Ikhsan et al,Sulfonated polybenzimidazole for low-alkalinity ion solvating membrane water electrolysis,nature Energy (2025). DOI: 10.1038/s41560-025-01876-9