The transition to sustainable energy systems necessitates efficient hydrogen production via water electrolysis, with anion-exchange membrane water electrolyzers (AEMWEs) emerging as a cost-effective alternative by combining the merits of alkaline water electrolyzers (AWEs) and proton-exchange membrane water electrolyzers (PEMWEs). However, challenges persist in membrane stability, oxygen evolution reaction (OER) kinetics, and mass transport efficiency. This review highlights the pivotal role of transition metal-based layered double hydroxides (LDHs) as high-performance, non-precious OER catalysts for AEMWEs, emphasizing their tunable electronic structures, abundant active sites, and alkaline stability. We systematically outline LDHs synthesis strategies (top-down/bottom-up approaches, and self-supporting LDHs engineering on the conductive substrates), and AEMWE component design, including membrane-electrode assembly optimization and ionomer-free architectures. Standardized evaluation protocols-short-circuit inspection, impedance spectroscopy, and durability assessment are detailed to benchmark performance. Moreover, recent advances in LDHs modification (cation/anion doping, heterojunction design, three-dimensional (3D) electrode structuring) are discussed for alkaline-fed systems, alongside emerging applications in seawater and pure-water electrolysis. By correlating material innovations with device-level metrics, this work provides a roadmap to address scalability challenges, offering perspectives on advancing AEMWEs for sustainable, large-scale hydrogen production.

The development of sustainable hydrogen production technologies is critical to addressing the global energy crisis and environmental challenges. Among water electrolysis systems, anion-exchange membrane water electrolyzers (AEMWEs) have gained attention for their ability to combine cost-effectiveness with high efficiency. However, AEMWEs face challenges such as sluggish oxygen evolution reaction (OER) catalysts with low conductivity and density of active sites, especially with the feed stock of pure water. In this study, a tri-metal Prussian blue analogue (PBA) was synthesized at room temperature and employed as an efficient OER pre-catalyst. Electrochemical activation of this as-prepared material in the alkaline solution generates highly active and conductive crystalline-amorphous metal (oxy)hydroxides as the true catalytic sites, which exhibited exceptional OER performance with the overpotential of 251 mV at 10 mA·cm^–2 and stable operation for 500 h in the alkaline solution. When applied as anode in AEMWEs, it delivered 1 A·cm^–2 at 1.72 and 2.20 V with the feedstock of alkaline solution (1 M KOH) and pure water, respectively, demonstrating its large application prospect in AEMWE.