Metal-organic Framework Materials Research Articles

Co-Carbonization of Straw and ZIF-67 to the Co/Biomass Carbon for Electrocatalytic Nitrate Reduction

Electrocatalytic nitrate reduction enables the recovery of nitrate from water under mild conditions and generates ammonia for nitrogen fertilizer feedstock in an economical and green means. In this paper, Co/biomass carbon (Co/BC) composite catalysts were prepared by co-carbonization of straw and metal–organic framework material ZIF-67 for electrocatalytic nitrate reduction using hydrothermal and annealing methods. The metal–organic framework structure disperses the catalyst components well and provides a wider specific surface area, which is conducive to the adsorption of nitrate and the provision of more reactive active sites. The introduction of biomass carbon additionally enhances the electrical conductivity of the catalyst and facilitates electron transport. After electrochemical testing, Co/BC-100 exhibited the best performance in electrocatalytic nitrate reduction to ammonia, with an ammonia yield of 3588.92 mmol gcat.−1 h−1 and faradaic efficiency of 97.01% at −0.5 V vs. RHE potential. This study provides a promising approach for the construction of other efficient cobalt-based electrocatalysts.

Gas adsorption and separation applications of MOF materials

Abstract. Low-carbon hydrocarbons (C1-C4) are really important raw materials used in making different kinds of big molecules and stuff in industries. Before, people mostly used super cold cooling and a method where stuff gets soaked up. But these ways need big machines and use a lot of energy. So, scientists are trying to make new ways to separate things that don't use as much energy. One great idea is using how different gases stick to things to separate them. This idea could be a brilliant way to replace the old methods. The most important part of this idea is making things that can stick to the gases. There's this special material called metal-organic frameworks (MOFs) that's a mix of things from nature and chemicals. It has tiny holes and places that can do special things, and it's being studied a lot for separating gases. Traditional porous materials like activated carbon, silica gel, and molecular sieves have been widely used in industries, which has greatly contributed to industrial growth and people's living standards. MOFs have changeable structures and spots that can do special things. By changing the metal bits or the organic parts, we can control the size of the holes in MOFs, the special spots, and how much surface they have. These things make MOFs useful for storing gases, separating stuff by sticking and making reactions happen in fields like chemistry [1-3]. This paper explores the categories of MOF applications.

Chemical warfare agents: Structure, properties, decontamination (part 1)

The review is aimed at summarizing and systematizing information on various methods of deactivation of chemical warfare agents required on the battlefield, in laboratories, research institutions, production facilities, as well as information on storage and destruction of poisonous substances. The review provides data on warfare poisons with different tactical and physiological characteristics and outlines the main directions of their neutralization, which are the most effective under the conditions of their real use. In the first part of this review, the methods of deactivation of warfare poisonous substances using functionalized metal-organic framework materials, on which reactions of their transformation into low-toxic products take place, are considered in detail. In addition, metal-organic frameworks are porous crystalline structures that have many areas of application and can be used as adsorbents and catalysts. The above material shows the importance of general knowledge about the physical and chemical properties of chemical warfare agents, the rate of their decomposition, the advantages and disadvantages of certain available technologies for their application. This review can be useful for finding new and improving known methods of decontamination of chemical warfare agents and other ecotoxicants, for environmental protection.

A Flexible Phosphonate Metal-Organic Framework for Enhanced Cooperative Ammonia Capture.

Ammonia (NH3) production in 2023 reached 150 million tons and is associated with potential concomitant production of up to 500 million tons of CO2 each year. Efforts to produce green NH3 are compromised since it is difficult to separate using conventional condensation chillers, but in situ separation with minimal cooling is challenging. While metal-organic framework materials offer some potential, they are often unstable and decompose in the presence of caustic and corrosive NH3. Here, we address these challenges by developing a pore-expansion strategy utilizing the flexible phosphonate framework, STA-12(Ni), which shows exceptional stability and capture of NH3 at ppm levels at elevated temperatures (100-220 °C) even under humid conditions. A remarkable NH3 uptake of 4.76 mmol g-1 at 100 μbar (equivalent to 100 ppm) is observed, and in situ neutron powder diffraction, inelastic neutron scattering, and infrared microspectroscopy, coupled with modeling, reveal a pore expansion from triclinic to a rhombohedral structure on cooperative binding of NH3 to unsaturated Ni(II) sites and phosphonate groups. STA-12(Ni) can be readily engineered into pellets or monoliths without losing adsorption capacity, underscoring its practical potential.

Activation and Catalysis of Methane over Metal–Organic Framework Materials

Activation and Catalysis of Methane over Metal–Organic Framework Materials

A 3D nitrogen-rich heat-resistant supramolecular MOF with superior energetic performances assembled from Zn(II) and 5-aminotetrazole

Heat-resistant explosives are pivotal for specialized applications demanding high thermal stability, essential in both civil and military sectors, especially in extreme environments. Our study focuses on the synthesis of a 3D nitrogen-rich supramolecular energetic metal-organic framework (MOF), Zn(ATZ)2 (1), using the 5-aminotetrazole (HATZ) ligand and Zn(II) ion. Structural analysis indicates that compound 1 adopts the orthorhombic CmCm space group and possesses a robust 2D network, characterized by strong π-π packing interactions between 2D layers, offering exceptional thermal stability up to 322 °C with minimal mechanical sensitivity. The standard molar enthalpy of formation (ΔfHo) and heat of detonation (ΔHdet) for compound 1 are calculated to be 7.08 kJ/g and 7.34 kJ/g, respectively. Remarkably, the ΔfHo of compound 1 significantly exceeds those of traditional heat-resistant explosives like RDX (0.32 kJ/g), HNS (0.17 kJ/g), TNT (–0.295 kJ/g), and TATB (–0.54 kJ/g), and is also higher than those of most reported energetic MOF materials. Similarly, its ΔHdet value surpasses those of common explosives such as TNT (4.144 kJ/g), HMX (5.525 kJ/g) and RDX (5.71 kJ/g), as well as the majority of reported energetic MOFs. Compound 1 also demonstrates impressive detonation properties with a velocity (D) of 7.22 km s-1 and a pressure (P) of 21.95 GPa, outperforming many other energetic MOF materials. These superior energetic characteristics position compound 1 as a strong candidate for heat-resistant explosives, showcasing its potential for future applications in demanding environments.

High-Valence Co Stabilized by In-Situ Growth of ZIF-67 on NiCo-LDH for Enhanced Performance in Oxygen Evolution Reaction.

The application of metal-organic frameworks (MOFs) in the electro-catalysis of heterogeneous structures is limited by the problems of low electrical conductivity and poor mechanical strength due to the complex synthesis process, although their high specific surface area and controllable structure. In this study, a method involving metal precipitation and ligand reaction is used during the electrochemical corrosion of hydroxides/oxy-hydroxides to obtain ZIF-67 in situ. The in situ growth technology not only effectively addresses the bonding strength and material conductivity challenges in the heterostructure between MOFs and the substrate but also enhances the catalyst's surface area and activity. Additionally, the exposure and protection of Co4+ by ZIF-67 contribute to the electrocatalyst's performance, demonstrating a low overpotential (η100) of 293mV, a Tafel slope of 25.8mV dec-1, and a charge transfer resistance of 3.9 Ω, with long-term robustness proven in continuous stability test exceeding 75000 s under the superhigh current density of 500mA cm-2. This work on binder-free in situ growth of MOFs not only provides relevant theoretical insights and experimental experience for cost-effective and controllable production of MOF-based catalysts but also offers ideas for the development of future electrocatalysts by exploring the exposure and protection of active site using MOFs materials.

Efficient low-temperature detection of CO gas by various metalated porphyrinic-Al-based MOF (Cu and Co) materials

A series of porphyrinic-Al-based metal–organic framework (MOF) nanomaterials were successfully fabricated via a simple solvothermal procedure and denoted as AlPMOF(M) (M = Cu, Co). The materials exhibited high surface areas with rectangular morphologies and the desired phases. Chemical composition studies demonstrated the presence of Cu and Co ions in the synthesized samples, while thermal studies showed the samples were stable up to 400 °C. CO gas-sensing studies revealed better CO sensing performances of both the AlPMOF(Cu) and AlPMOF(Co) gas sensors compared to the pristine sensor at room temperature. AlPMOF sensor showed responses of 1.06 and 1.05 to 10 ppm CO gas at 150 and 25ºC, respectively, with no selectivity to CO gas at 25ºC. AlPMOF (Co) sensor revealed responses of 1.11 and 1.06 to 10 ppm CO gas at 200 and 25ºC, respectively, with selectivity to CO gas at 25ºC. Also, AlPMOF (Cu) sensor revealed responses of 1.12 and 1.07 to 10 ppm CO gas at 150 and 25ºC, respectively, with selectivity to CO gas at 25ºC. In addition, the sensing mechanism and enhanced response to CO gas were elucidated. These findings demonstrate the capability of these novel sensing materials for CO gas sensing at low temperatures.

Hierarchical structural design of cobalt sulphide nanoparticles/nickel sulphide for high-performance supercapacitors

Metal-organic framework (MOF) materials have become increasingly attractive in supercapacitor electrode research because of their regular crystal topology and tunable pore distribution. The strategy for the synthesis of the Ni3S4/Co3S4 electrode material with a layered structure was successfully devised using the layered Ni-MOF as a template and precursor. The characterisation techniques of XRD, FTIR, XPS, SEM, TEM and BET have provided confirmation of the assertion that the Ni3S4/Co3S4 composites exhibit an advanced hierarchical pore structure and considerable specific surface area. The specific capacity of the Ni3S4/Co3S4 composite is as high as 122.8 mAh g−1, and it can still maintain 72.6 % of the specific capacity after 3,000 cycles. Furthermore, the SEM morphology remains largely unchanged after cycling, which demonstrates excellent stability. Moreover, honeycomb-shape porous carbon (N-HAPC) with ultra-high specific surface area was selected as negative electrode material to fabricate a novel hybrid supercapacitor (Ni3S4/Co3S4//N-HAPC), which exhibits a broad operational voltage range of 1.6 V and superior energy density of 28.6 Wh kg−1. Simultaneously, HSCs exhibited remarkable charge-discharge stability, exhibiting a mere 17.2 % decline in capacitance stability following 7,000 GCD cycles. The combination of two Ni3S4/Co3S4//N-HAPC HSCs in series has been demonstrated to be capable of illuminating a small LED lamp, indicating the potential for their use in practical applications. Furthermore, this approach offers a novel strategy for the structural design of MOF-like materials.

A novel dual-function fluorescence sensor Eu/CDs@MOF-808 for the sensitive detection of adenosine triphosphate and uric acid

Designing and developing a reliable method for the detection of potential biomarker molecules are crucial for the early prevention and diagnosis of diseases. In this study, we present a novel functionalized metal–organic framework material (MOF-808) that is developed to construct ratiometric fluorescence sensing platforms (Eu/CDs@MOF-808) for the detection of adenosine triphosphate (ATP) and uric acid (UA). The fluorescent probe Eu/CDs@MOF-808 prepared through the in-situ encapsulation of fluorescent carbon dots (CDs) within the structure of MOF-808 exhibits excellent optical properties. Additionally, rare earth ions (Eu3+) are incorporated into the CDs@MOF-808 using a post-synthetic modification strategy. The presence of ATP significantly enhances the characteristic peak of carbon dots (CDs) at 440 nm, while the peak of Eu3+ at 614 nm remains relatively unchanged. Furthermore, the concentration of ATP exhibits a strong linear relationship with the ratiometric fluorescence intensity (F440/F614) in the concentration range of 0.5–450 μM, with a detection limit of 0.22 μM. Notably, the addition of uric acid (UA) to this fluorescence sensing platform leads to a marked reduction in the characteristic peak intensity of Eu3+, which results in a satisfactory linear relationship between the ratiometric fluorescence intensity and UA concentration in the concentration ranges of 0.04–300 μM and 300–650 μM, with a detection limit of 0.04 μM. Additionally, the fluorescent sensor has been successfully applied for the detection of ATP and UA in real serum and urine samples.

Defective porous urchin-like ZnO/NiO microspheres-coated solid-phase microextraction fiber for analysis of trace polychlorinated biphenyls in milk.

Owing to the high lipophilicity of polychlorinated biphenyls (PCB), they easily accumulate in dairy products. Although usually present at very low levels, they pose a serious threat to human health. Therefore, developing a sensitive and reliable method for detecting PCB in dairy products is crucial. Herein, Herein, a metal-organic framework (MOF) material named with bimetallic nodes and double ligands was prepared as a precursor using a one-pot hydrothermal method. Defective porous urchin-like ZnO/NiO, derived from these MOF-based precursors (ZnNi-MOF-NH2) as a sacrificial template, was synthesized via pyrolysis to remove heat-sensitive ligands. To the best of our knowledge, this urchin-like nanostructured ZnO/NiO hybrid was utilized as a solid-phase microextraction (SPME) coating for the first time. Headspace SPME (HS-SPME) was developed for non-contact extraction of PCB in milk prior to gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis. Under optimal conditions, the HS-SPME-GC-MS/MS method exhibited a wide linear range (0.01-1000ng·L-1), low limits of detection (0.003-0.025ng·L-1), and high enrichment factors (5714-9906). Additionally, the performance of the ZnO/NiO SPME fiber coating showed no noticeable decrease after 175 uses. The method was applied to trace PCB analysis in milk samples, yielding recoveries of 70.3-114.1%. The ZnO/NiO derived from MOF-based material provides a promising candidate for SPME coatings to extract PCB and other analogs.

Trace benzene capture by decoration of structural defects in metal-organic framework materials.

Capture of trace benzene is an important and challenging task. Metal-organic framework materials are promising sorbents for a variety of gases, but their limited capacity towards benzene at low concentration remains unresolved. Here we report the adsorption of trace benzene by decorating a structural defect in MIL-125-defect with single-atom metal centres to afford MIL-125-X (X = Mn, Fe, Co, Ni, Cu, Zn; MIL-125, Ti8O8(OH)4(BDC)6 where H2BDC is 1,4-benzenedicarboxylic acid). At 298 K, MIL-125-Zn exhibits a benzene uptake of 7.63 mmol g-1 at 1.2 mbar and 5.33 mmol g-1 at 0.12 mbar, and breakthrough experiments confirm the removal of trace benzene (from 5 to <0.5 ppm) from air (up to 111,000 min g-1 of metal-organic framework), even after exposure to moisture. The binding of benzene to the defect and open Zn(II) sites at low pressure has been visualized by diffraction, scattering and spectroscopy. This work highlights the importance of fine-tuning pore chemistry for designing adsorbents for the removal of air pollutants.

A review of the progress of metal-organic frameworks in perovskite solar cells

Organic-inorganic hybrid perovskite solar cells (PSCs) have emerged as substantial challenges for future generations of photovoltaic apparatus, largely attributed to their power conversion efficiency (PCE) drastically elevated from below 10% to a staggering 25.7% over the past decade. Owing to characteristics distinct to them like substantial specific surface areas, copious binding locations, adjustable nanostructures, and mutual reinforcement, metal-organic frameworks (MOFs) are commonly utilized as either supplementary components or operational layers for augmenting both the efficiency and durability of PSCs. This paper primarily underlines the recent advancements in implementing MOFs across various operational strata of a PSC. The focal points of this study encompass an examination of the photovoltaic yields, the repercussions, and the advantages of fusing MOF materials into constituents like perovskite absorbers, electron transport, and hole transport layers, in addition to interface layers. The study also extends to an exploration of how MOFs effectively inhibit leakages of Pb2+ within halide perovskites and their associated apparatus. This paper concludes by discerning and shedding light on potential research prospects for the deployment of MOFs in PSCs.

Copper-based photocatalysts with natural organic ligands for efficient removal of tetracycline under visible light

The excessive use of broad-spectrum antibiotics, such as tetracycline, presents a significant challenge to human survival and development. Oxygen vacancies (OVs) metal-organic framework (MOF) materials were synthesized using natural organic acids (L-malic acid, L-aspartic acid, and L-asparagine) with similar structures but different charge densities, along with copper as the metal linking agent. The presence of oxygen vacancies in the catalyst provides abundant active sites for photocatalytic reactions. The employment of flexible straight-chain organic ligands devoid of rigid polycyclic rings, combined with the incorporation of different substituents to induce variations in charge density, the resulting catalysts exhibit distinct photocatalytic activities under visible light. Density functional theory calculations confirm that L-asparagine exhibits the largest electron density difference, and the Cu-based MOF (Cu-ASU) synthesized as an organic ligand exhibits the highest photocatalytic activity under visible light excitation. The catalyst displayed remarkable photocatalytic activity against tetracycline antibiotics under identical conditions (with removal rates of 93.5 % for tetracycline, 81.4 % for terramycin, and 95.6 % for chloramphenicol hydrochloride). This provides a novel approach for the design and synthesis of photocatalysts for the removal of antibiotics from water.

Application of Y-MOF-CNT-Derived Y2O3-C@CNT Composites in Lithium-Sulfur Battery Separators.

In order to mitigate the shuttle effect of lithium polysulfides in lithium-sulfur batteries, we propose a yttrium-metal-organic framework-carbon nanotube (Y-MOF-CNT)-derived Y2O3-C@CNT composite for modifying the separator in this study. The Y-MOFs, comprising yttrium (Y) rare earth metal and terephthalic acid, exemplify a prototypical category of metal-organic framework (MOF) materials. They manifest the advantageous attributes associated with MOFs while concurrently possessing distinctive catalytic traits ascribed to rare earth elements. In this study, Y-MOF nanoparticles were synthesized on carbon nanotube (CNT) substrates via a facile aqueous solution method, succeeded by high-temperature carbonization to yield Y2O3-C@CNT composite materials. These composites were subsequently employed as coatings on one side of polyethylene (PE) separators. The resultant Y2O3-C@CNT composite inherits the particle-like morphology and porosity from its precursor Y-MOF, alongside the inherent conductivity in carbon-based materials. This amalgamation is conducive to polysulfide capture and catalytic conversion processes within lithium-sulfur batteries. The application of the Y2O3-C@CNT-coated PE separator effectively mitigated polysulfide shuttle effects and significantly enhanced the battery electrochemical performance. At a sulfur loading level of 3 mg cm-2 under a 0.5 C rate, an initial discharge specific capacity of 900 mAh g-1 was achieved. After 400 cycles, the discharge specific capacity remained at 483.85 mAh g-1 with a capacity retention rate of 53.7%. Upon increasing sulfur loading to 5 mg cm-2, the discharge specific capacity at a lower rate (0.1 C) reached 817.8 mAh g-1; even after 100 cycles, it maintained a value of 700 mAh g-1 with a capacity retention rate of 85.6%. Notably, our modified Y2O3-C@CNT separator demonstrated exceptional cycling stability, even under conditions involving high sulfur loading.

Unlocking of Hidden Mesopores for Enzyme Encapsulation by Dynamic Linkers in Stable Metal‐Organic Frameworks

AbstractMesoporous metal‐organic frameworks (MOFs) are promising supports for the immobilization of enzymes, yet their applications are often limited by small pore apertures that constrain the size of encapsulated enzymes to below 5 nm. In this study, we introduced labile linkers (4,4′,4′′‐(2,4,6‐boroxintriyl)‐tribenzoate, TBTB) with dynamic boroxine bonds into mesoporous PCN‐333, resulting in PCN‐333‐TBTB with enhanced enzyme loading and protection capabilities. The selective breaking of B−O bonds creates defects in PCN‐333, which effectively expands both window and cavity sizes, thereby unlocking hidden mesopores for enzyme encapsulation. Consequently, this strategy not only increases the adsorption kinetics of small enzymes (&lt;5 nm) such as cytochrome c (Cyt C) and horseradish peroxidase (HRP), but also enables the immobilization of various large‐sized enzymes (&gt;5 nm), such as glycoenzymes. The glycoenzymes@PCN‐333‐TBTB platform was successfully applied to synthesize thirteen complex oligosaccharides and polysaccharides, demonstrating high activity and enhanced enzyme stability. The dynamic linker‐mediated enzyme encapsulation strategy enables the immobilization of enzymes exceeding the inherent pore size of MOFs, thus broadening the scope of enzymatic catalytic reactions achievable with MOF materials.

Ultralong Room-Temperature Phosphorescence in Ca(II) Metal-Organic Frameworks Based on Nicotinic Acid Ligands.

In recent years, metal-organic framework (MOF) materials with long persistent luminescence (LPL) have inspired extensive attention and presented various applications in security systems, information anticounterfeiting, and biological imaging fields. However, obtaining LPL materials with ultralong lifetime remains challenging. Halogen atoms, as nonmetallic elements existing in the frameworks, can not only induce the heavy-atom effect, effectively enhancing spin-orbit coupling and promoting intersystem crossing (ISC) processes, but also suppress non-radiative transition of the triplet states through the intra- and intermolecular interactions. Specifically, fluorine atoms with the strongest electronegativity may form intermolecular aggregate interlockings through halogen-bonding interactions that restrict molecular motions and vibrations, thereby improving phosphorescent lifetime. With the aforementioned considerations, two distinct types of MOFs with/without fluorine atoms (namely, Ca-MOF and 5FCa-MOF) were synthesized. Notably, by introducing fluorine atoms into MOFs, fluorine-induced intermolecular aggregate interlockings effectively enhanced the phosphorescent lifetime of 5FCa-MOF exceeding 264 ms compared to that of Ca-MOF (103.94 ms). Remarkably, both MOFs displayed bright LPL to the naked eye after removal of the irradiation source, especially 5FCa-MOF which can last for about 2 s. By introducing fluorine atoms, 5FCa-MOF exhibits greatly enhanced ISC with a rate constant up to 4.1 × 106 s-1 and suppressed non-radiative decay down to 3.73 s-1, thereby extending the LPL time. The thus obtained LPL provides potential in information encryption, security systems, optical anticounterfeiting, and so on.

Efficient Nanofibrous Electromagnetic Wave Absorber Inspired by Spider Silk Hunting.

With the rapid advancements in wireless communication and radar detection technologies, there has been a significant uptick in the utilization frequency of electromagnetic waves across both civilian and military sectors, consequently generating substantial electromagnetic radiation and interference. These electromagnetic pollutants present a considerable threat to public health and information security. Consequently, materials capable of absorbing and mitigating electromagnetic pollution have garnered significant attention.The nanomaterials with multiple components and various heterogeneous interfaces have been considered as preferred efficient electromagnetic wave (EMW) absorbers. In this work, carbon nanofibers doped with magnetic metal oxide particles (Co/Ni-CNFs) are prepared by electrospinning and heat treatment. In these samples, the minimum reflection loss can reach -40.13dB at 4.6mm, and the widest effective absorption bandwidth is 4.4GHz. The excellent microwave absorption is attributed to the appropriate impedance matching. The electromagnetic parameters of Co/Ni-CNFs are balanced by adjusting the concentration of magnetic metal-organic framework material (MOFs) in the precursor solution. It is believed that this work can provide a reference for developing lightweight, flexible, and robust electromagnetic wave-absorbing materials.

Crystallographic and Optical Spectroscopic Study of Metal–Organic 2D Polymeric Crystals of Silver(I)– and Zinc(II)–Squarates

Metal–organic framework materials, as innovative functional materials for nonlinear optical technologies, feature linear and nonlinear optical responses, such as a laser damage threshold, outstanding mechanical properties, thermal stability, and optical transparency. Their non-centrosymmetric crystal structure induces a higher-order nonlinear optical response, which guarantees technological applications. ZnII– and AgI–squarate complexes are attractive templates for these purposes due to their good crystal growth, optical transparency, high thermal stability, etc. However, the space group type of the catena-((μ2-squarato)-tetra-aqua-zinc(II)) complex ([Zn(C4O4)(H2O)4]) is debatable, (1) showing centro- and non-centrosymmetric monoclinic C2/c and Cc phases. The same is valid for the catena-((μ3-squarato)-(μ2-aqua)-silver(I)) complex (Ag2C4O4), (2) exhibiting, so far, only a C2/c phase. This study is the first to report new crystallographic data on (1) and (2) re-determined at different temperatures (293(2) and 300(2)K) and the non-centrosymmetric Cc phase of (2), having different numbers of molecules per unit cell compared with the C2/c phase. There are high-resolution crystallographic measurements of single crystals, experimental electronic absorption, and vibrational spectroscopic data, together with ultra-high-resolution mass spectrometric ones. The experimental results are supported for theoretical optical and nonlinear optical properties obtained via high-accuracy static computational methods and molecular dynamics, using density functional theory as well as chemometrics.

Metal‐Organic Framework Materials as Bifunctional Electrocatalyst for Rechargeable Zn‐Air Batteries

AbstractRechargeable Zn‐air batteries offer the advantages of environmental friendliness, safety, low prices and high energy density, and are highly valued. However, the major challenge faced by rechargeable Zn‐air batteries nowadays is the low energy efficiency due to the slow reaction kinetics of electrocatalyst at the air cathode. Bifunctional catalysts are key to the development of Zn‐air batteries by improving their overall performance and long‐term cycling stability. Metal‐organic framework (MOF) materials have shown great benefits as oxygen electrocatalysts in promoting oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). This paper reviews the recent advances of three kinds of MOF materials as bifunctional catalysts for rechargeable Zn‐air batteries. Additionally, this paper also discusses the synthetic design strategy of MOF composite derivatives, and concludes by suggesting the application of MOF materials in the field of rechargeable Zn‐air batteries.