Defect Creation in HKUST‐1 via Molecular Imprinting: Attaining Anionic Framework Property and Mesoporosity for Cation Exchange Applications

Discovering new methods to tailor the physical and chemical properties of metal–organic frameworks (MOFs) for their numerous potential applications is highly desired. In this work, engineering defects in MOF via a molecular imprinting approach is developed to endow HKUST‐1, a well‐studied classical MOF, with hierarchical structure, mesoporosity, and anionic framework property. Ringlike anionic HKUST‐1 (HKUST‐1‐R) and a wide variety of metal‐doped isostructural analogues (M/HKUST‐1‐R, M = Ca, Cd, Ce, Co, Li, Mn, Na, Ni, or Zn) are obtained. The benefits of transforming imprinted HKUST‐1‐R to M/HKUST‐1‐R are further demonstrated for various applications. This synthetic strategy is therefore suitable for rational design and functionalization of MOFs in addition to their morphological control in nanoscale.     

Biocatalytic Metal–Organic Frameworks: Prospects Beyond Bioprotective Porous Matrices

Biocatalytic metal–organic framework (MOF) composites, synthesized by interfacing MOFs with biocatalytic components, possessing the unprecedented synergetic properties that are hard to achieve via conventional strategies, represent one of the next‐generation composite materials for diverse biotechnological applications. Research on the applications of biocatalytic MOFs is still in its preliminary stage, with a wide variety of studies focusing on the bioprotection role of MOFs. However, their diversity of building units, molecular‐scale tunability, modular synthetic routes, and more detailed understanding of the heterogeneous MOF‐biointerface could even lead to completely new applications and potentials beyond the current imagination. The most recent progress in biocatalytic MOFs presents ground‐breaking applications in smart and tunable biocatalysis, precision nanomedicine, vaccine and gene delivery, biosensing, and nano‐biohybrids. Herein, the general and advanced synthesis strategies for improving the material properties of biocatalytic MOFs, from tuning biocatalytic activity to framework stability to synergistic properties with other materials, are summarized. Then, the latest state‐of‐the‐art applications of the biocatalytic MOF systems and recent advanced developments that are shaping this emerging field are surveyed. Finally, to define promising research directions, a critical evaluation and future prospects for the potential applications of biocatalytic MOFs are provided.     

Versatile Surface Functionalization of Metal–Organic Frameworks through Direct Metal Coordination with a Phenolic Lipid Enables Diverse Applications

A novel strategy for the versatile functionalization of the external surface of metal‐organic frameworks (MOFs) has been developed based on the direct coordination of a phenolic‐inspired lipid molecule DPGG (1,2‐dipalmitoyl‐sn‐glycero‐3‐galloyl) with metal nodes/sites surrounding MOF surface. X‐ray diffraction and Argon sorption analysis prove that the modified MOF particles retain their structural integrity and porosity after surface modification. Density functional theory calculations reveal that strong chelation strength between the metal sites and the galloyl head group of DPGG is the basic prerequisite for successful coating. Due to the pH‐responsive nature of metal‐phenol complexation, the modification process is reversible by simple washing in weak acidic water, showing an excellent regeneration ability for water‐stable MOFs. Moreover, the colloidal stability of the modified MOFs in the nonpolar solvent allows them to be further organized into 2 dimensional MOF or MOF/polymer monolayers by evaporation‐induced interfacial assembly conducted on an air/water interface. Finally, the easy fusion of a second functional layer onto DPGG‐modified MOF cores, enabled a series of MOF‐based functional nanoarchitectures, such as MOFs encapsulated within hybrid supported lipid bilayers (so‐called protocells), polyhedral core‐shell structures, hybrid lipid‐modified‐plasmonic vesicles and multicomponent supraparticles with target functionalities, to be generated. for a wide range of applications.     

Metal–Organic Frameworks Derived from Zero‐Valent Metal Substrates: Mechanisms of Formation and Modulation of Properties

The replicative construction of metal–organic frameworks (MOFs) templated with solvent‐insoluble solid substrates is of marked importance, as it allows for the assembly of 2D and 3D macro‐ and mesoscopic architectures with properties that are challenging to attain by the conventional solution‐based synthesis approach. This work reports an in situ and direct construction of MOFs from zero‐valent metal substrates via a green hydrothermal oxidation–MOF construction chemistry without the use of any additional metal source, chemical reagents, or acidification of solvent, and elucidates the zero‐valent metal derived formation mechanisms of MOFs and their structure modulation to 1D nanofibers (NFs), 2D film, and 3D core–shell microstructures. Through modulation of the competing surface oxidation‐dissolution and MOF crystallization kinetics, Al@MIL‐53 core–shell microstructures and MIL‐53 (Al) NFs are obtained that exhibit unique morphologies and marked properties superior to the conventional MIL‐53 (Al) powders. The generality of zero‐valent metal‐templated synthesis of MOFs is demonstrated with formation of MIL‐53 (Al), HKUST‐1, and ZIF‐7 polycrystalline films on Al, Cu, and Zn metal meshes, elucidating the significance of the approach utilizing solid metal substrate that can be easily processed into various shapes, architectures, and compositions.     

Negative Thermal Expansion Design Strategies in a Diverse Series of Metal–Organic Frameworks

Negative thermal expansion materials are of interest for an array of composite material applications whereby they can compensate for the behavior of a positive thermal expansion matrix. In this work, various design strategies for systematically tuning the coefficient of thermal expansion in a diverse series of metal–organic frameworks (MOFs) are demonstrated. By independently varying the metal, ligand, topology, and guest environment of representative MOFs, a range of negative and positive thermal expansion behaviors are experimentally achieved. Insights into the origin of these behaviors are obtained through an analysis of synchrotron‐radiation total scattering and diffraction experiments, as well as complementary molecular simulations. The implications of these findings on the prospects for MOFs as an emergent negative thermal expansion material class are also discussed.     

Metal–Organic Frameworks with Boronic Acid Suspended and Their Implication for cis‐Diol Moieties Binding

Introduction of accessible boronic acid functionality into metal–organic frameworks (MOFs) might to endow them with desired properties for potential applications in recognition and isolation of cis‐diol containing biomolecules (CDBs). However, no investigation is found to address this topic until now. Herein, Cr‐based MOFs of MIL‐100 (MIL stands for Materials from Institut Lavoisier) integrated with different pendent boronic acid group (MIL‐100‐B) are reported. This new functional material is successfully prepared using a simple metal–ligand–fragment coassembly (MLFC) strategy with isostructure to the parent MIL‐100 as verified by X‐ray diffraction characterization. The integration and content tunability of the boronic acid group in the framework are confirmed by X‐ray photoelectron spectroscopy and ¹¹B NMR. Transmission electron microscopy reveals that MIL‐100‐B can evolve into well‐defined morphology and nanoscale size at optimized boronic acid incorporating level. The obtained MOFs exhibit comparable surface areas and pore volumes with parent MIL‐100 and present exceptional chemical stability in a wide pH range. The inherent boronic acid components in MIL‐100‐B can effectively serve as the recognition units for the cis‐diol moieties and consequently enhance the capture capabilities for CDBs. The exceptional chemical stability, high porosity, and good reusability as well as the intrinsic cis‐diol moieties recognition function prefigure great potential of the current MIL‐100‐B in CDBs purification, sensing, and separation applications.     

Single‐Crystal‐to‐Single‐Crystal Transformation of a Europium(III) Metal–Organic Framework Producing a Multi‐responsive Luminescent Sensor

A sensor with a red‐emission signal is successfully obtained by the solvothermal reaction of Eu³⁺ and heterofunctional ligand bpydbH₂ (4,4′‐(4,4′‐bipyridine‐2,6‐diyl) dibenzoic acid), followed by terminal‐ligand exchange in a single‐crystal‐to‐single‐crystal transformation. As a result of treatments both before and after the metal–organic framework formation, accessible Lewis‐base sites and coordinated water molecules are successfully anchored onto the host material, and they act as signal transmission media for the recognition of analytes at the molecular level. This is the first reported sensor based on a metal–organic framework (MOF) with multi‐responsive optical sensing properties. It is capable of sensing small organic molecules and inorganic ions, and unprecedentedly it can discriminate among the homologues and isomers of aliphatic alcohols as well as detect highly explosive 2,4,6‐trinitrophenol (TNP) in water or in the vapor phase. This work highlights the practical application of luminescent MOFs as sensors, and it paves the way toward other multi‐responsive sensors by demonstrating the incorporation of various functional groups into a single framework.     

Tunable Electrochemistry of Electrosynthesized Copper Metal–Organic Frameworks

Metal–organic frameworks (MOFs) synthesized using different organic ligands are expected to have varied morphology and properties. Herein, three copper MOFs (Cu‐MOFs) are electrosynthesized using a simple and direct reduction approach and three organic ligands: 1,3,5‐benzenetricarboxylic acid, 1,4‐benzenedicarboxylic acid, and 1,2,4,5‐benzenetetracarboxylic acid. The as‐synthesized Cu‐MOFs exhibit varied morphology. Their electrochemistry is further explored via investigating the natures of their capacitive, faradaic, and electrocatalytic behavior. The stability of these Cu‐MOFs is also checked during the course of electrochemical measurements. The secondary built units of organic ligands with copper ions are found theoretically and experimentally to determine both the morphology and active sites of Cu‐MOFs. Namely the electrochemistry of Cu‐MOFs is dependent on the used organic ligands. Cu‐MOF synthesized using 1,3,5‐benzenetricarboxylic acid owns better electrochemistry than that using 1,4‐benzenedicarboxylic acid or 1,2,4,5‐benzenetetracarboxylic acid. These MOFs keep their compositions and crystallinity unchanged in short times but loss them for long electrochemical running times. Therefore, the properties and applications of MOFs are designable and can be optimized during the course of reduction electrosynthesis processes via selecting organic ligands and metal ions.     

Thermal Shrinkage Behavior of Metal–Organic Frameworks

Thermal treatment of metal–organic frameworks (MOFs) as a post‐treatment approach has grown in popularity and resulted in various MOF‐derived materials. However, the widely used extreme thermolytic conditions (usually above 500 °C) lead to degradation in the well‐defined MOFs intrinsic properties. This work demonstrates that MIL‐101 calcined at medium‐temperature range (200–280 °C) partially breaks the coordination bonds that can introduce more accessible active sites, exhibiting a 10‐fold increase in oxidation activity while retaining its intrinsic structure and porosity. Another fascinating feature of MIL‐101 calcined in this temperature range is their temperature‐dependent shrinkage behavior, which is also found in many other types of MOFs. Based on different shrinkage ratios of various MOFs, yolk–shell MOFs@MOFs structures can be constructed through nonsacrificial template method. Overall, the structural and morphological evolution process of MOFs treated in the medium‐temperature range can open new horizons to develop efficient MOFs catalysts and design complex structures.     

Tunable Emission in Heteroepitaxial Ln‐SURMOFs

By using a layer‐by‐layer (LbL) approach, lanthanide‐based, monolithic metal–organic framework (MOF) thin films are fabricated for optical applications. In particular, the LbL approach allows manufacturing of heteroepitaxial Tb(III)‐Eu(III)(BTC) coatings with precise thickness control. Adjusting the Tb(III)‐to‐Eu(III) ratio allows tuning of the emission color. The hetero‐multilayer architecture makes it possible to suppress the direct Tb(III)‐to‐Eu(III) energy transfer, an unwanted phenomenon present in the corresponding mixed‐metal bulk MOF structures. The resulting Ln‐MOF thin films, or Ln‐surface‐anchored MOFs (SURMOFs), are characterized by X‐ray diffraction, infra‐red reflection absorption spectroscopy, UV–vis, and photoluminescence measurements. The results demonstrate that the heteroepitaxial SURMOF architectures carry huge potential for fabricating optical coatings for a wide range of applications.     

Ultrafast Melting of Metal–Organic Frameworks for Advanced Nanophotonics

The conversion of metal–organic frameworks (MOFs) into derivatives with a well‐defined shape and composition is considered a reliable way to produce efficient catalysts and energy capacitors at the nanometer scale. Yet, approaches based on conventional melting of MOFs provide the derivatives such as amorphous carbon, metal oxides, or metallic nanoclusters with an appropriate morphology. Here ultrafast melting of MOFs is utilized by femtosecond laser pulses to produce a new generation of derivatives with complex morphology and enhanced nonlinear optical response. It is revealed that such a nonequilibrium process allows conversion of interpenetrated 3D MOFs comprising flexible ligands into well‐organized spheres with a metal oxide dendrite core and amorphous organic shell. The ability to produce such derivatives with a complex morphology is directly dependent on the electronic structure, crystal density, ligand flexibility, and morphology of initial MOFs. An enhanced second harmonic generation and three‐photon luminescence are also demonstrated due to the resonant interaction of 100–1000 nm spherical derivatives with light. The results obtained are in the favor of new approaches for melting special types of MOFs for nonlinear nanophotonics.     

Massive Anisotropic Thermal Expansion and Thermo‐Responsive Breathing in Metal–Organic Frameworks Modulated by Linker Functionalization

Functionalized metal–organic frameworks (fu‐MOFs) of general formula [Zn₂(fu‐L)₂dabco]_n show unprecedentedly large uniaxial positive and negative thermal expansion (fu‐L = alkoxy functionalized 1,4‐benzenedicarboxylate, dabco = 1,4‐diazabicyclo[2.2.2]octane). The magnitude of the volumetric thermal expansion is more comparable to property of liquid water rather than any crystalline solid‐state material. The alkoxy side chains of fu‐L are connected to the framework skeleton but nevertheless exhibit large conformational flexibility. Thermally induced motion of these side chains induces extremely large anisotropic framework expansion and eventually triggers reversible solid state phase transitions to drastically expanded structures. The thermo‐responsive properties of these hybrid solid–liquid materials are precisely controlled by the choice and combination of fu‐Ls and depend on functional moieties and chain lengths. In principle, this combinatorial approach allows for a targeted design of extreme thermo‐mechanical properties of MOFs addressing the regime between crystalline solid matter and the liquid state.     

Visible Light Triggered CO2 Liberation from Silver Nanocrystals Incorporated Metal–Organic Frameworks

Widespread deployment of metal–organic frameworks (MOFs) for CO₂ capture remains challenging due to the great energy‐penalty associated with their regeneration. To overcome this challenge, a new type of photodynamic carbon capture material synthesized by incorporating Ag nanocrystals with UiO‐66 (Ag/UiO‐66) framework is presented. Upon the irradiation of visible light, Ag nanocrystals within the composites serve as “nanoheaters” to convert photon energy into thermal energy locally. Driven by such light‐induced localized heat (LLH), the adsorbed CO₂ within MOFs is remotely released. The CO₂ desorption capacity of such Ag/UiO‐66 composites can be readily regulated by control over their Ag contents and the applied light intensity. Up to 90.5% of CO₂ desorption is achieved under the investigated conditions. Distinct from the traditional light‐responsive MOFs for gas trigger release, currently developed LLH‐driven CO₂ release method not only offers a promising solution to the heat‐insulating nature of MOFs, but also demonstrates a potentially low energy method to remotely regenerate MOF adsorbents given the utilization of naturally abundant visible light as efficient stimulus.     

Engineering Fe–Fe3C@Fe–N–C Active Sites and Hybrid Structures from Dual Metal–Organic Frameworks for Oxygen Reduction Reaction in H2–O2 Fuel Cell and Li–O2 Battery

Dual metal–organic frameworks (MOFs, i.e., MIL‐100(Fe) and ZIF‐8) are thermally converted into Fe–Fe₃C‐embedded Fe–N‐codoped carbon as platinum group metal (PGM)‐free oxygen reduction reaction (ORR) electrocatalysts. Pyrolysis enables imidazolate in ZIF‐8 rearranged into highly N‐doped carbon, while Fe from MIL‐100(Fe) into N‐ligated atomic sites concurrently with a few Fe–Fe₃C nanoparticles. Upon precise control of MOF compositions, the optimal catalyst is highly active for the ORR in half‐cells (0.88 V in base and 0.79 V versus RHE in acid in half‐wave potential), a proton exchange membrane fuel cell (0.76 W cm^?2 in peak power density) and an aprotic Li–O₂ battery (8749 mAh g^?1 in discharge capacity), representing a state‐of‐the‐art PGM‐free ORR catalyst. In the material, amorphous carbon with partial graphitization ensures high active site exposure and fast charge transfer simultaneously. Macropores facilitate mass transport to the catalyst surface, followed by oxygen penetration in micropores to reach the infiltrated active sites. Further modeling simulations shed light on the true Fe–Fe₃C contribution to the catalyst performance, suggesting Fe₃C enhances oxygen affinity, while metallic Fe promotes *OH desorption as the rate‐determining step at the nearby Fe–N–C sites. These findings demonstrate MOFs as model system for rational design of electrocatalyst for energy‐based functional applications.     

Bimetal–Organic Framework: One‐Step Homogenous Formation and its Derived Mesoporous Ternary Metal Oxide Nanorod for High‐Capacity,High‐Rate,and Long‐Cycle‐Life Lithium Storage

Metal–organic frameworks (MOFs) and relative structures with uniform micro/mesoporous structures have shown important applications in various fields. This paper reports the synthesis of unprecedented mesoporous Ni_xCo_3?xO₄ nanorods with tuned composition from the Co/Ni bimetallic MOF precursor. The Co/Ni‐MOFs are prepared by a one‐step facile microwave‐assisted solvothermal method rather than surface metallic cation exchange on the preformed one‐metal MOF template, therefore displaying very uniform distribution of two species and high structural integrity. The obtained mesoporous Ni_0.3Co_2.7O₄ nanorod delivers a larger‐than‐theoretical reversible capacity of 1410 mAh g^?1 after 200 repetitive cycles at a small current of 100 mA g^?1 with an excellent high‐rate capability for lithium‐ion batteries. Large reversible capacities of 812 and 656 mAh g^?1 can also be retained after 500 cycles at large currents of 2 and 5 A g^?1, respectively. These outstanding electrochemical performances of the ternary metal oxide have been mainly attributed to its interconnected nanoparticle‐integrated mesoporous nanorod structure and the synergistic effect of two active metal oxide components.     

Hierarchically Porous Multimetal‐Based Carbon Nanorod Hybrid as an Efficient Oxygen Catalyst for Rechargeable Zinc–Air Batteries

The lack of efficient strategies to address the intrinsic activity, site accessibility, and structural stability issues of metal‐carbon hybrid catalysts is restricting their real‐world implementation on the basis of rechargeable zinc–air batteries. Herein, a dual metal–organic frameworks (MOFs) pyrolysis strategy is developed to regulate the intrinsic activity and porous structure of the derived catalysts, where a Fe₂Ni_MIL‐88@ZnCo_zeolitic imidazolate framework (ZIF), with a hierarchically porous structure, multifunctional components, and an integrated architecture, acts as an ideal precursor to obtain multimetal based porous nanorod (FeNiCo@NC‐P). Benefitting from the synergetic effect of the multimetal components, facilitated reactant accessibility, and the well‐retained integrated structure, the resultant FeNiCo@NC‐P catalyst exhibits an oxygen reduction reaction half‐wave potential of 0.84 V as well as an oxygen evolution reaction potential of 1.54 V at 10 mA cm^–2. Furthermore, the practical application of FeNiCo@NC‐P in the zinc–air battery displays a low voltage gap and long‐term durability (over 130 h at a current density of 10 mA cm^–2), which outperforms the commercial noble metal benchmarks. This work not only affords a competitive bifunctional oxygen electrocatalyst for zinc–air batteries but also paves a new way to design and fabricate MOF‐derived materials with tunable catalytic properties.     

Hollow Multivoid Nanocuboids Derived from Ternary Ni–Co–Fe Prussian Blue Analog for Dual‐Electrocatalysis of Oxygen and Hydrogen Evolution Reactions

Hydrogen generation from electrochemical water‐splitting is an attractive technology for clean and efficient energy conversion and storage, but it requires efficient and robust non‐noble electrocatalysts for hydrogen and oxygen evolution reactions (HER and OER). Nonprecious transition metal–organic frameworks (MOFs) are one of the most promising precursors for developing advanced functional catalysts with high porosity and structural rigidity. Herein, a new transition metal‐based hollow multivoid nanocuboidal catalyst synthesized from a ternary Ni–Co–Fe (NCF)‐MOF precursor is rationally designed to produce dual‐functionality toward OER and HER. Differing ion exchanging rates of the ternary transition metals within the prussian blue analog MOF precursor are exploited to produce interconnected internal voids, heteroatom doping, and a favorably tuned electronic structure. This design strategy significantly increases active surface area and pathways for mass transport, resulting in excellent electroactivities toward OER and HER, which are competitive with recently reported single‐function nonprecious catalysts. Moreover, outstanding electrochemical durability is realized due to the unique rigid and interconnected porous structure which considerably retains initial rapid charge transfer and mass transport of active species. The MOF‐based material design strategy demonstrated here exemplifies a novel and versatile approach to developing non‐noble electrocatalysts with high activity and durability for advanced electrochemical water‐splitting systems.     

Preconcentration of Nitroalkanes with Archetype Metal–Organic Frameworks (MOFs) as Concept for a Sensitive Sensing of Explosives in the Gas Phase

Thermal desorption based enrichment is a general concept that can enhance any detection system's sensitivity and selectivity. Given their large interior surface area and chemical versatility, archetype metal–organic frameworks (MOFs) are selected for preconcentration of explosives and their precursors occurring in low concentrations, and are compared to the state‐of‐the‐art sorbent Tenax TA . Applying inverse gas chromatography (iGC), this study shows that several archetype MOFs, namely HKUST‐1 and MIL‐53 , surpass Tenax regarding their specific retention volume for nitromethane, a typical ingredient in improvised explosives. Using linear hydrocarbons as reference probe molecules, the dispersive surface energy is determined for all MOFs along with the specific contribution of the nitro group for HKUST‐1 and ZIF‐8 . Trends from pulse‐chromatographic iGC‐investigations are mostly followed in breakthrough and thermal desorption experiments using a 1000 ppm nitromethane source. In these experiments, HKUST‐1 proves the peak substance, with enrichment factors being 109‐fold higher than for Tenax , followed by MIL‐53 . In case of HKUST‐1 , this factor is successfully reproduced for a 1 ppm concentration scenario. This shows that archetype MOFs can be suitable or even superior candidates for a sensitive sensing of nitroalkane explosives from the gas phase by a concept of preconcentration.     

Sublimation‐Vapor Phase Pseudomorphic Transformation of Template‐Directed MOFs for Efficient Oxygen Evolution Reaction

Using vapor phase transformation to synthesize template‐directed metal–organic frameworks (MOFs) shows great promise as an approach to avoid the shortcomings of solution‐based strategies. However, among current research, either the products are confined to zeolitic imidazolate frameworks or the conversion technologies are limited to complex processes such as chemical vapor deposition. Here, a well‐designed sublimation‐vapor phase pseudomorphic transformation method is reported to fabricate vertically aligned nanosheet arrays of NiFe‐based MOFs with a uniform and controlled thickness, derived from NiFe‐layered double hydroxides. Benefiting from the optimized morphology and the high intrinsic activity originating from the synergistic coupling effect of NiFe metal clusters, the as‐prepared MOF electrocatalyst displays a superior oxygen evolution reaction performance, requiring an overpotential of 318 mV at 50 mA cm^?2 with a Tafel slope of only 47 mV dec^?1. Furthermore, a string of metal oxide‐MOFs are obtained, demonstrating the universality of this strategy. By observing the different stages of transformation, the transformation and growth mechanism of MOF crystals is unveiled for the first time. These findings may inspire the exploration and preparation of more species of MOFs, further broadening their application areas.     

Hybrid 2D Dual‐Metal–Organic Frameworks for Enhanced Water Oxidation Catalysis

Metal–organic frameworks (MOFs) and MOF‐derived nanostructures are recently emerging as promising catalysts for electrocatalysis applications. Herein, 2D MOFs nanosheets decorated with Fe‐MOF nanoparticles are synthesized and evaluated as the catalysts for water oxidation catalysis in alkaline medium. A dramatic enhancement of the catalytic activity is demonstrated by introduction of electrochemically inert Fe‐MOF nanoparticles onto active 2D MOFs nanosheets. In the case of active Ni‐MOF nanosheets (Ni‐MOF@Fe‐MOF), the overpotential is 265 mV to reach a current density of 10 mA cm^?2 in 1 m KOH, which is lowered by ≈100 mV after hybridization due to the 2D nanosheet morphology and the synergistic effect between Ni active centers and Fe species. Similar performance improvement is also successfully demonstrated in the active NiCo‐MOF nanosheets. More importantly, the real catalytic active species in the hybrid Ni‐MOF@Fe‐MOF catalyst are unraveled. It is found that, NiO nanograins (≈5 nm) are formed in situ during oxygen evolution reaction (OER) process and act as OER active centers as well as building blocks of the porous nanosheet catalysts. These findings provide new insights into understanding MOF‐based catalysts for water oxidation catalysis, and also shed light on designing highly efficient MOF‐derived nanostructures for electrocatalysis.