Cover credits: Korea Institute of Science and Technology (KIST)
In recent years, hydrogen has attracted considerable attention as a potential clean energy source as an alternative to fossil fuels. In particular, there has been active research and development of water electrolysis technology that extracts hydrogen from water to generate green energy and prevents greenhouse gas emissions.
The proton exchange membrane water electrolyzer (PEMWE) technology holds core material technology and uses expensive noble metal-based catalysts and perfluorocarbon-based proton exchange membranes.
This technology translates into high production costs for systems.
To address these limitations of the conventional technology, a research team in Korea has recently developed core technology for the next-generation water electrolysis system that has significantly improved the durability and performance while significantly lowering the cost of producing green hydrogen energy.
AEMWE, which uses an anion exchange membrane and electrode binder, does not rely on the expensive platinum group-metal electrodes and replaces the separator plate material of the water electrolysis cell with iron instead of titanium. By comparing the price of the catalyst and the single separator material, the cost of manufacturing is reduced by about 3000 times that of the existing PEMWE. However, it has not been used commercially due to its poor performance relative to MSW and sustainability concerns of less than 100 hours of sustained operation.
The research team developed poly(fluorenyl-co-aryl piperidinium) (PFAP) – based anion exchange materials (electrolyte membrane and electrode binder) with high ion conductivity and durability under alkaline conditions by increasing the specific surface area within the structure and based on this technology, a membrane electrode assembly was developed. The developed material had excellent durability of over 1000 hours of operation and achieved a new record airframe performance of 7.68 A/cm2. This is approximately six times the efficiency of existing anion exchange materials and approximately 1.2 times that of expensive commercial PEMWE technology (6 A/cm2).
The technology has overcome the performance and durability issues of the core materials pointed out as limitations in the AEMWE technology to date and has raised the quality of the technology to such a level that allows replacement of the PEMWE technology. In addition to excellent performance and durability, the commercialization of the developed anion exchange materials is ongoing with the integration of large capacity and large-area applications.
Dr. So Young Lee of KIST commented,
“Our team has developed a material and high-efficiency technology that goes beyond the limitations of the existing water electrolysis technology. This technology is expected to lay the foundation for introducing the next-generation water electrolysis technology that allows a significant reduction of the cost involved in the green hydrogen production.”
The article “High-performance anion exchange membrane water electrolyzers with a current density of 7.68 A cm−2 and a durability of 1000 hours” appeared on Energy & Environmental Science.