Recent advances in electrocatalysts for anion exchange membrane water electrolysis: design strategies and characterization approaches

With the growing demand for sustainable energy, hydrogen is recognized as a key clean energy carrier that can stabilize renewable sources like solar and wind. Traditional hydrogen production primarily relies on grey hydrogen from fossil fuels, which produces significant CO₂ emissions. In contrast, anion exchange membrane water electrolysis (AEMWE) offers a promising pathway to green hydrogen, combining the zero-gap design of proton exchange membrane water electrolysis with the alkaline environment of alkaline water electrolysis. This configuration allows AEMWE to operate with lower KOH concentrations, enhancing safety and enabling cost-effective, earth-abundant transition metals as electrocatalysts for hydrogen and oxygen evolution reactions (HER and OER). Herein, we examine the fundamental principles of AEMWE, including its cell components, reaction mechanisms, and various in situ characterization methods. Additionally, it explores recent progress in optimizing HER and OER electrocatalysts, focusing on both precious and non-precious metal designs. We also discuss the prospects for AEMWE in industrial-level applications, underscoring its potential as an efficient, durable, and economically viable technology for sustainable hydrogen production.