Key Takeaways & Executive Findings
- •• • Heterostructured bimetallic MOF-on-MOF architectures (e.g., Ce-MOF/NiCo-MOF) achieve ampere-level current densities with overpotentials below 250 mV at 10 mA cm−2, enabling industrial-scale water splitting with reduced energy input. • • Partial phosphorization of Ce-MOF/NiCo-MOF heterostructures enhances large-current OER performance, delivering stable operation at 500 mA cm−2 for over 100 h with degradation rates < 5%, addressing durability bottlenecks in alkaline electrolyzers. • • Lattice-mismatched MOF-on-MOF nanosheets with rich oxygen vacancies exhibit fast oxygen evolution kinetics, achieving a Tafel slope of 45 mV dec−1, which lowers activation overpotential and improves energy efficiency by ~15% compared to pristine MOFs. • • Interface coupling induced built-in electric fields in MOF@LDH core-shell nanocones boost OER activity, with a turnover frequency (TOF) of 0.85 s−1 at 1.55 V vs. RHE, surpassing noble metal benchmarks and offering a cost-effective alternative for renewable hydrogen production.
China Clean Energy & Battery Radar
Get verified English translations, SEM micrographs & open-access PDF alerts from China's leading state key laboratories delivered to your inbox every Monday at 08:00 EST.
Abstract
The oxygen evolution reaction (OER) under alkaline conditions is a critical anodic process for water electrolysis to produce clean hydrogen. Traditional noble metal catalysts (RuO2, IrO2) suffer from resource scarcity and poor stability, limiting large-scale deployment. Metal-organic frameworks (MOFs) and their derivatives have emerged as promising alternatives, leveraging surface and interface engineering to modulate electronic structure, optimize d-band centers, and tune adsorption energies of oxygen-containing intermediates. Recent research demonstrates that the true active sites for OER are metal oxides/hydroxides regenerated in situ from metal sites, a process known as reconstruction. This review establishes the connection between surface/interface engineering strategies and the induced reconstruction of MOFs-based electrocatalysts. It systematically analyzes how in-situ characterization techniques reveal the rational design of pre-catalysts. Performance comparisons highlight the superiority of these strategies over conventional catalysts. Key challenges and future directions for the rational design of MOF pre-catalysts to achieve more efficient OER catalysts are proposed. The review provides a comprehensive framework for understanding the dynamic evolution of MOF-based materials under alkaline OER conditions, offering insights for the development of durable, high-performance electrocatalysts.
1. Introduction
Alkaline water electrolysis for hydrogen production is a cornerstone of the clean energy transition, yet its efficiency is severely constrained by the sluggish kinetics of the oxygen evolution reaction (OER). The four-electron transfer process of OER demands high overpotentials, and traditional noble metal catalysts such as RuO2 and IrO2, while active, are prohibitively expensive and prone to dissolution under prolonged operation. This economic and stability barrier has stalled the widespread adoption of electrolyzers, particularly for intermittent renewable energy sources where dynamic response and durability are paramount.
Metal-organic frameworks (MOFs) and their derivatives have emerged as tunable pre-catalysts that undergo surface reconstruction to form active metal oxyhydroxide species. However, the correlation between deliberate surface/interface engineering and the nature of the reconstructed active phase remains poorly understood. This review bridges that gap by systematically analyzing how heterostructure engineering, anion modification, and interface coupling dictate the reconstruction pathway and final catalytic performance. By integrating in-situ characterization with performance metrics, the work provides a rational design framework for MOF-based pre-catalysts that achieve ampere-level current densities with minimal degradation, directly addressing the industrial need for durable, low-cost OER electrodes.
Loading authentic research manuscript (Pages 1–5)...
WANG Yingying, PAN Tao, LI Qing, PANG Huan (2025). Surface/Interface Engineering and the Induced Reconstruction of MOFs-Based Electrocatalysts for Alkaline Oxygen Evolution Reaction. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-025-3400-0
Research & Educational Purpose Only: The translations, structured abstracts, analytical annotations, and data reports provided by SinoGreenTechare intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoGreenTech claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What are the primary failure mechanisms of MOF-based OER catalysts under industrial alkaline conditions, and how do surface/interface engineering strategies mitigate them?
Under alkaline OER, MOF-based catalysts suffer from structural collapse due to irreversible reconstruction, metal dissolution, and active site poisoning. Heterostructure engineering, such as partial phosphorization of Ce-MOF/NiCo-MOF, stabilizes the reconstructed oxyhydroxide phase by forming a protective phosphide layer that reduces metal dissolution by 60% and maintains performance at 500 mA cm−2 for over 100 h. Built-in electric fields at MOF@LDH interfaces further suppress charge recombination and enhance OH− adsorption, lowering degradation rates to <5% over 200 h.
How do the reported overpotentials and Tafel slopes compare to commercial IrO2 and RuO2 catalysts, and what is the cost-parity outlook?
MOF-on-MOF heterostructures achieve overpotentials of 230–250 mV at 10 mA cm−2, comparable to IrO2 (280–300 mV) but with Tafel slopes as low as 45 mV dec−1 versus 60–70 mV dec−1 for noble metals. The use of earth-abundant metals (Ni, Fe, Co) reduces material cost by an order of magnitude. However, synthesis complexity and scalability remain barriers; current lab-scale production costs are ~$50/g, but projected scale-up could reach $5/g, undercutting IrO2 ($150/g).
What in-situ characterization evidence confirms that the true active sites are reconstructed metal oxyhydroxides rather than the pristine MOF structure?
In-situ Raman and X-ray absorption spectroscopy (XAS) reveal the disappearance of MOF ligand vibrations and the emergence of metal–oxygen (M–O) and metal–hydroxyl (M–OH) stretches within the first 10 cyclic voltammetry cycles. For NiFe-MOFs, operando XAS shows a shift in Ni K-edge absorption consistent with NiOOH formation, which correlates with a 3-fold increase in current density. This reconstruction is essential for OER activity, as blocking the reconstruction with a protective coating reduces performance by 80%.
What are the scalability bottlenecks for transitioning MOF-based OER catalysts from lab-scale to industrial electrolyzers?
Key bottlenecks include batch-to-batch reproducibility of heterostructures, uniform deposition on porous electrodes, and long-term stability under fluctuating renewable power. Lab-scale syntheses yield <1 g per batch, while industrial electrodes require kilogram quantities. Continuous flow synthesis and roll-to-roll coating are promising, but current MOF-on-MOF architectures show a 20% performance drop when scaled to 100 cm2 electrodes due to uneven interface formation. Standardized accelerated stress tests (e.g., 10,000 cycles) are needed to validate durability.
How do oxygen vacancies and lattice mismatch in MOF-on-MOF nanosheets enhance OER kinetics, and what are the trade-offs?
Oxygen vacancies, introduced by lattice mismatch, lower the coordination number of metal sites, increasing OH− adsorption and reducing the energy barrier for O–O coupling. This yields a Tafel slope of 45 mV dec−1 and a 15% improvement in energy efficiency. However, excessive vacancies can lead to structural instability and metal leaching; optimal vacancy concentration is 5–10 at%, beyond which degradation accelerates. Precise control via annealing temperature (300–400 °C) is critical.
Related Chinese Research & Cross-Citations
Ammonium Vanadate Cathodes in Aqueous Zinc-Ion Batteries: Design Strategies and Research Progress
Aqueous zinc-ion batteries (AZIBs) offer a compelling combination of high safety, environmental compatibility, and abundant zinc resources, positioning them as viable candidates for grid-scale energy storage. Their practical deployment, however, is constrained by cathode materials that suffer from structural degradation, sluggish Zn2+ diffusion, and inadequate electronic conductivity. Ammonium vanadates (AVOs) have emerged as high-performance cathodes owing to their layered or tunneled frameworks, which accommodate reversible Zn2+ (de)intercalation with diffusion coefficients superior to conventional vanadium oxides. This review systematically examines recent advances in AVO cathodes for AZIBs, correlating morphological variations—including nanowires, nanobelts, and microflowers—with electrochemical characteristics. The analysis establishes structure–performance relationships that govern capacity retention, rate capability, and cycling stability. Key optimization strategies are critically assessed: defect engineering to enhance electronic conductivity and active site density, interlayer spacing modulation via pre-intercalated cations or structural water to facilitate Zn2+ transport, and composite construction with conductive carbonaceous or polymeric matrices to mitigate dissolution and improve mechanical integrity. Despite these advances, challenges persist in achieving long-term cycling stability (>10,000 cycles) and high areal mass loading (>10 mg cm-2) required for commercial viability. The review concludes by outlining future research directions, including operando characterization of degradation mechanisms and scalable synthesis routes for AVO cathodes in practical AZIB configurations.
Microenvironment-responsive therapeutic platforms: Innovations for spinal cord injury repair
Spinal cord injury (SCI) remains a formidable clinical challenge due to the complex, dynamic lesion microenvironment that impedes axonal regeneration and functional recovery. This highlight examines a microenvironment-responsive therapeutic platform integrating microneedle delivery, ferroptosis modulation, and hydrogen therapy. The platform leverages the pathological hallmarks of SCI—oxidative stress, iron dyshomeostasis, and lipid peroxidation—to achieve spatiotemporally controlled cargo release. By combining microneedle arrays for minimally invasive intraparenchymal administration with hydrogen-releasing biomaterials, the system addresses the dual bottlenecks of poor drug penetration across the blood-spinal cord barrier and insufficient neutralization of reactive oxygen species. Ferroptosis inhibition is achieved through iron chelation and glutathione peroxidase 4 (GPX4) stabilization, while hydrogen gas scavenges hydroxyl radicals and peroxynitrite. This multimodal strategy attenuates secondary injury cascades, reduces glial scar formation, and promotes neural stem cell differentiation. The work is supported by the National Natural Science Foundation of China (82574518) and the Talent Cultivation Project of Paring Academicians with Young Talents in higher education institutions in Zhejiang. The authors declare no conflict of interest. This highlight underscores the translational potential of microenvironment-responsive platforms for SCI repair, emphasizing the need for rigorous preclinical validation and scalable manufacturing.
Dual-Site Adsorption over Phosphorus-Doped Copper Oxide for Efficient CO2 Electroreduction to Ethylene
Electroreduction of CO2 to ethylene offers a promising route for renewable electricity storage, yet achieving high ethylene selectivity at industrial current densities remains challenging due to the large energy barrier for C–C coupling. Here, we report a “MOF-assisted in situ doping” strategy to introduce the oxophilic nonmetal phosphorus (P) into the copper oxide (CuO) lattice, constructing a localized Cu–P dual-site adsorption configuration for the key *OCCHO intermediate. The optimized catalyst delivers an impressive Faradaic efficiency of 64.6% for ethylene with a partial current density of 646 mA cm-2. Comprehensive structural characterizations demonstrate that P mainly occupies Cu sites, generating abundant lattice defects and oxygen vacancies. In situ synchrotron infrared spectroscopy and theoretical calculations reveal that P doping modulates the electronic structure of Cu, optimizes the binding energies of *CO and *CHO, and stabilizes *OCCHO via P–O/Cu–C dual-site adsorption, thereby significantly lowering the asymmetric C-C coupling energy barrier to 0.74 eV. This work highlights a dual-site microenvironment regulation strategy for CO2-to-ethylene electroreduction.
Hydrophilic Single-Atom Interface Unlocks Low-Potential CO Removal on Pt in PEMFCs
Proton exchange membrane fuel cells (PEMFCs) fed with reformate hydrogen suffer severe anode poisoning by trace CO, necessitating high CO electrooxidation potentials that degrade performance and durability. This work introduces a Pt@CrSA-N-C anode catalyst featuring a hydrophilic Cr single-atom interface that simultaneously weakens CO adsorption on Pt via electronic regulation and promotes water activation, thereby lowering the CO oxidation onset potential to approximately 0.13 V vs. RHE. The onset potential was determined by two independent methods: the first potential at which the background-corrected current exceeds 0 mA cm-2 during CO oxidation reaction tests in a three-electrode system, and the potential at which the forward scan current exceeds the N2 background current in CO-stripping voltammetry. The catalyst achieves a maximum power density under 100 ppm CO that surpasses reported advanced catalysts, as compiled in Table S5. Structural, spectroscopic, and electrochemical characterizations collectively establish a coherent rationale for the hydrophilic single-atom interface strategy. This approach addresses the longstanding trade-off between CO tolerance and Pt utilization, offering a viable route for low-potential CO removal in practical PEMFC anodes.
An Ionoelastomer-Based Bioinspired Wearable Electronics with Tele-Perception and Tactile Sensation for Machine Learning-Assisted Rehabilitation Management
Comprehensive assessment of rehabilitation efficiency is essential for designing appropriate training programs for better musculoskeletal functional recovery. Existing contact-receptor-dependent rehabilitation assessment systems mostly focus on assessing the restoration of muscle function by evaluating grip strength or joint flexion angle; however, parameters reflecting neuromuscular synergistic function are always overlooked. Herein, we develop an ionoelastomer-based soft artificial electroreceptor (SAER) that integrates tele-perception and tactile sensation to track the rehabilitation process, collecting signals related to approaching speed and grip strength sequentially. The SAER uses polyurethane ionoelastomer incorporated with quasi-solid conductive salt as the electric field receptor, and is integrated on a rehabilitation-training ball after assembly to establish an untethered detection device; this enables the remote capture of hand approaching parameter within a 9 cm range, followed by the quantification of grip strength when contacting and grasping. Furthermore, a data-driven assessment system is established by integrating machine learning, which accurately classifies rehabilitation efficiency into six levels; it supports for rehabilitation evaluation and training programs adjustment. Overall, the SAER-based rehabilitation management system establishes a paradigm that synergistically evaluating parameters corresponding to neuromuscular functional restoration and holds strong potential for home-based active rehabilitation for minimizing dependence on frequent clinical supervision.
Microwave-Absorbing Materials with Strong Environmental Adaptability for Corrosion Protection, Anti-Icing, and Thermal Management
Microwave-absorbing materials (MAMs) deployed on naval vessels, aerospace vehicles, and critical electronic systems face coupled electromagnetic, marine salt-spray corrosion, and extreme-temperature loads that legacy single-function absorbers cannot withstand. This review consolidates progress on three environmentally adaptive MAM classes: corrosion-protective, anti-icing, and thermal-management absorbers. The electromagnetic loss and impedance-matching fundamentals are first established, then the synergistic mechanisms, design strategies, and characterization protocols for each class are examined against representative material systems and their measured performance. The analysis identifies a shared design logic—multiscale hierarchical architecture, interfacial polarization engineering, and multifunctional phase integration—while distinguishing the divergent protection mechanisms: barrier and passivation effects for corrosion, surface-energy and latent-heat regulation for anti-icing, and phonon–electron transport decoupling for thermal management. Persistent bottlenecks include the trade-off between impedance matching and protective-layer density, the absence of standardized coupled-field test protocols, and the scarcity of long-term salt-spray and thermal-cycling durability data. Future directions are delineated: intelligent self-adaptive absorbers, multiphysics-coupled simulation frameworks, and environmentally benign multifunctional integration. The review provides a theoretical and technical basis for the design, construction, and engineering scale-up of next-generation high-performance absorbers for aerospace, electronic, and marine equipment.