Efficient catalysts are required to reduce energy consumption in electrocatalytic hydrogen production reactions. Although noble metal oxides such as RuO₂ and IrO₂ show excellent activity, high cost and instability under high potential hinder scalability. Layered double hydroxides (LDHs) offer a low-cost alternative with tunable metal compositions, flexible 2D structure, and abundant oxygen sites. Still, only metal atoms at edges are catalytically active, layer stacking decreases surface availability, and intrinsic conductivity remains weak. Understanding reaction mechanisms including adsorbate evolution (AEM) and lattice oxygen mechanism (LOM)—is essential to overcome kinetic limits and improve electron transport. Addressing these challenges requires further in-depth research on structural and electronic modulation to advance LDH-based catalysts for the oxygen evolution reaction (OER)..
Researchers from Zhengzhou University and the University of Surrey published (DOI: 10.1016/j.esci.2025.100380) a comprehensive review in eScience (September 2025) summarizing recent advances in electronic defect engineering for LDH-based oxygen evolution catalysts. The paper systematically categorizes defect types, characterizations, and performance-enhancing mechanisms, offering a roadmap for designing highly active and stable LDHs for alkaline water electrolysis. The review highlights metal vacancies, oxygen vacancies, heteroatom doping, single-atom loading, and interlayer modification as core strategies to boost intrinsic activity and unlock LOM pathways.
The review outlines three major electronic defect categories: metal vacancies, oxygen vacancies, and heteroatom incorporation, that explains how each influences electronic structure and reaction kinetics. Metal vacancies create unsaturated metal coordination sites with high-energy dangling bonds, enhancing OH adsorption and accelerating O–O bond formation. Oxygen vacancies modulate electron density near metal sites, lower band gap, and promote faster charge transfer, while also enabling lattice-oxygen-involved mechanisms. Heteroatom doping—including transition metals (Co, V, Cr), rare-earth elements (Ce, Gd, Er), and even noble metals (Ru, Ir, Au) that reshapes electron distribution and stabilizes high-valence catalytic states.
Advanced characterization tools such as HAADF-STEM, XAS/EXAFS, and EPR allow atomic-scale visualization of defects and surface reconstruction during OER. The authors further discuss lattice strain regulation, interlayer anion exchange, and single-atom anchoring, which break traditional scaling relationships and significantly reduce OER overpotential. Combining defect engineering with theoretical simulations (DFT) provides reliable descriptors to guide rational design of catalysts that approach volcano-curve optimization. Overall, the review demonstrates how atomic-level electronic tailoring pushes LDHs beyond conventional performance limits.
“We are entering an era where catalytic performance can be programmed through electrons rather than elements,” the authors note. They emphasize that controlling vacancy distribution and redox states offers more powerful tuning capability than traditional composition optimization. As they suggest, the next breakthroughs will likely emerge from integrating electronic-defect simulations with operando spectroscopy, enabling real-time observation of lattice oxygen behavior and active-site evolution. Such insight is essential for revealing rate-determining steps, balancing AEM–LOM pathways, and achieving industrial-level catalytic stability.
The study provides a blueprint for developing LDH electrocatalysts capable of powering large-scale hydrogen fuel production, metal-air batteries, CO₂ reduction systems, and renewable energy storage devices. By mastering defect chemistry, researchers may construct catalysts that match or surpass noble metals while cutting material costs dramatically. Looking forward, combining defect engineering with machine learning and in-situ monitoring could accelerate catalyst discovery and enable automated structure-performance prediction. This approach lays the foundation for efficient, durable water-splitting technologies that support future clean-energy infrastructure worldwide.
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References
DOI
10.1016/j.esci.2025.100380
Original Source URL
https://doi.org/10.1016/j.esci.2025.100380
Funding information
We acknowledge financial support from the National Natural Science Foundation of China [52171082, 52301291, 52403406], the China Postdoctoral Science Foundation [2023TQ0305], Natural Science Foundation Project for Outstanding Youth of Henan Province [232300421013], and Nuclear Material Technology Innovation Fund for National Defense Technology Industry [ICNM−2023−YZ−02]. This work was also supported partially by Science and Technology Department of Henan Province [241111232100, 241111242100, 231111240500].
About eScience
eScience – a Diamond Open Access journal cooperated with KeAi and published online at ScienceDirect. eScience is founded by Nankai University (China) in 2021 and aims to publish high quality academic papers on the latest and finest scientific and technological research in interdisciplinary fields related to energy, electrochemistry, electronics, and environment. eScience provides insights, innovation and imagination for these fields by built consecutive discovery and invention. Now eScience has been indexed by SCIE, CAS, Scopus and DOAJ. Its first impact factor is 36.6, which is ranked first in the field of electrochemistry.