Metal-organic Framework Electrode Research Articles

Drastically enhancing the cycle stability of copper-dicarboxylate as an anode material for lithium-ion batteries by rational fluorination

Metal-organic frameworks (MOFs) are extensively investigated in lithium-ion batteries because of their large specific surface area, adjustable chemical properties, porous structure, and rich reaction sites. However, the severe capacity attenuation of MOF electrodes has been one of the hardest obstacles hindering the further application of MOFs, due to the embedding and de-embedding of lithium ions during the cycles leading to the structural disintegration and volume fluctuation. Inspired by the wide application of fluorinated additives in commercial electrolytes, a typical carboxylate MOF, copper 1,4-benzenedicarboxylate is fluorinated molecularly to improve its cycle stability. Without enough fluorine source for a robust SEI film, the performance of fluorine-free copper 1,4-benzenedicarboxylate degrades rapidly to 99.5 mAh/g in the initial 21 cycles at a current density of 100 mA g−1, while its fluorinated counterpart, copper tetrafluoroterephthalate, delivers drastically enhanced cycle stability and maintains a reversible specific capacity of 575.5 mAh/g after 500 cycles, due to the SEI-promoting effect of fluorine in the framework. The present fluorination strategy is proved effective and can be extended in much wider applications of MOF materials.

Energy Enhancement of a Nickel–Cobalt-Mixed Metallic Metal–Organic Framework Electrode and a Potassium Iodide Redox Mediator Bound with an Aqueous Electrolyte for High-Performance Redox-Aided Asymmetric Supercapacitors

Enhancing the energy density of a supercapacitor requires the use of novel electrode and electrolyte materials that can withstand high voltages and have rapid electrochemical kinetics. Pesudocapacitance, high energy density, and specific capacitance may be provided by electrodes and redox mediator electrolytes used in redox-aided asymmetric supercapacitor equipment (RAASC), which are essential for their practical implementation. In this work, the rod and microsphere structure of the Ni/Co-mixed metal-organic framework (MOF) positive electrode material was synthesized using the hydrothermal method. Because of the high proposition of active sites and fluent ionic channels created by the rod and microsphere structure, as-prepared Ni/Co-MOF materials were used as three different organic linkers. CNN-MOF material has a rodlike structure and good capacitance value, so we further increase the capacitance value that we introduced in a KI redox mediator bound with a KOH electrolyte, and in this combination, a high specific capacitance up to 612 F g-1 was reached in a three-electrode system. Additionally, an electrical double layer capacitor nature of the graphite anode material with CNN-MOF as a cathode material and a KI redox mediator bound with the KOH gel polymer electrolyte was observed in the assembled RAASC. The RAASC device had reached a high energy density of 84.2 W h kg-1 with a power density of 532 W kg-1. At the same time, it showed good cyclic stability and could retain 97.4% of initial capacitance after 11,200 charge and discharge cycles. This work demonstrates efficient fabrication of high-performing MOF electrodes, and the fabrication of KI redox electrolyte-constructed RAASC devices offers a novel window into the creation of cutting-edge energy storage devices.

Regulating Exposed Facets of Metal-Organic Frameworks for High-rate Alkaline Aqueous Zinc Batteries.

Metal-organic frameworks (MOFs) have drawn growing attention as promising electrode candidates for rechargeable batteries. However, most studies focus on the direct use of MOF electrodes without any modification. Post-synthetic modification, a judicious tool to modify targeted properties of MOFs, has been long-neglected in the field of batteries. Herein, crystal-facet engineering is proposed to design MOF-based electrodes with high capacity and fast electrochemical kinetics. We found that a thermally-modified strategy can regulate the dominant exposed facet of Ni-based MOF (PFC-8). With the optimally exposed facets, the battery exhibited admirable rate capability (139.4 mAh g-1 at 2.5 A g-1 and 110.0 mAh g-1 at 30 A g-1 ) and long-term stability. Furthermore, density functional theory calculations demonstrate that stronger OH- adsorption behaviors and optimized electronic structures induced by the regulated exposed facets boost the electrochemical performance.

Conductive Metal-Organic Frameworks for Supercapacitors.

As a class of porous materials with crystal lattices, metal-organic frameworks (MOFs), featuring outstanding specific surface area, tunable functionality, and versatile structures, have attracted huge attention in the past two decades. Since the first conductive MOFissuccessfully synthesized in 2009, considerable progress has been achieved for the development of conductive MOFs, allowing their use in diverse applications for electrochemical energy storage. Among those applications, supercapacitors have received great interest because of their high power density, fast charging ability, and excellent cycling stability. Here, the efforts hitherto devoted to the synthesis and design of conductive MOFs and their auspicious capacitive performance are summarized. Using conductive MOFs as a unique platform medium, the electronic and molecular aspects of the energy storage mechanism in supercapacitors with MOF electrodes are discussed, highlighting the advantages and limitations to inspire new ideas for the development of conductive MOFs for supercapacitors.

Understanding the Influence of Particle Morphology on the Capacitive Performance of Conductive Layered Metal-Organic Frameworks

Two-dimensional layered metal-organic frameworks (MOFs), characterised by their combined high intrinsic porosities and electrical conductivities, have emerged as one of the most promising electrode materials for next-generation energy storage devices, particularly supercapacitors. Several such MOFs have displayed encouraging performances in supercapacitors with a wide range of electrolytes, and have exhibited specific and areal capacitances on par with or exceeding state-of-the-art carbon materials.1-3 This has raised the prospect of using these materials in commercial devices, and their well-defined structures make them promising model electrode materials for supercapacitor structure-property investigations. However, layered MOFs can be synthesised with a range of particle morphologies, and hence 3D pore structures, as well as different degrees of particle agglomeration. Minimal work has been performed to understand how these factors impact the capacitive performances of these frameworks, and existing literature has struggled with small differences in observed morphology and low control over the samples.4 This has cast doubts over reported results, and has hindered both the development of MOF-based supercapacitors and their implementation as model electrodes.In this work, a greater variation in particle morphology was obtained than observed in previous work on this topic. This was achieved by synthesising samples of the layered conductive MOF Cu3(HHTP)2, (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) with different modulating agents, which influence the equilibrium determining the self-assembly process of a MOF and regulate the rate of framework growth. Using this approach, we present a detailed study into the influence of particle morphology and agglomeration on the capacitive performance of the layered MOF Cu3(HHTP)2 in symmetric supercapacitors with both organic and ionic liquid electrolytes. These studies reveal that ‘flake-like’ particle morphologies with very small length-to-width aspect ratios (<< 1) and little agglomeration are optimal for layered MOF supercapacitors. This sample displayed greater rate capabilities with organic electrolytes and significantly higher specific capacitances with ionic liquid electrolytes compared to ‘rod-like’ particles, with much larger length-to-width aspect ratios, and heavily agglomerated samples. These findings will pave the way for the next generation of supercapacitor devices using conductive layered MOF electrodes. Figure 1

In Situ Synthesis of MOF‐74 Family for High Areal Energy Density of Aqueous Nickel–Zinc Batteries

Limited by single metal active sites and low electrical conductivity, designing nickel-based metal-organic framework (MOF) materials with high capacity and high energy density remains a challenge. Herein, a series of bi/multimetallic MOF-74 family materials in situ grown on carbon cloth (CC) by doping Mx+ ions in Ni-MOF-74 is fabricated: NiM-MOF@CC (M = Mn2+ , Co2+ , Cu2+ , Zn2+ , Al3+ , Fe3+ ), and NiCoM-MOF@CC (M = Mn2+ , Zn2+ , Al3+ , Fe3+ ). The type and ratio of doping metal ions can be adjusted while the original topology is preserved. Different metal ions are confirmed by X-ray absorption fine structure (XAFS). Furthermore, these Ni-based MOF electrodes are directly utilized as cathodes for aqueous nickel-zinc batteries (NZBs). Among all the as-prepared electrodes, NiCo-MOF@CC-3 (NCM@CC-3), with an optimized Co/Ni ratio of 1:1, exhibits the best electrical conductivity, which is according to the density functional theory (DFT) theoretical calculations. The NCM@CC-3//Zn@CC battery achieves a high specific capacity of 1.77 mAh cm-2 , a high areal energy density of 2.97 mWh cm-2 , and high cycling stability of 83% capacity retention rate after 6000 cycles. The synthetic strategy based on the coordination effect of metal ions and the concept of binder-free electrodes provide a new direction for the synthesis of high-performance materials in the energy-storage field.

Multiscale design of 3D metal–organic frameworks (M−BTC, M: Cu, Co, Ni) via PLAL enabling bifunctional electrocatalysts for robust overall water splitting

Multiscale structural engineering of high-performance bifunctional electrocatalysts to influence hydrogen and oxygen evolution reactions (HER and OER) has a significant role in overall water splitting. Thus, we successfully designed a new strategy and synthesized transition-metal-based 3D metal–organic framework (MOF) materials having various architectures, namely, Cu–BTC, Co–BTC, and Ni–BTC, by pulsed laser ablation in dimethylformamide. The coordination between the metal and carboxylate moieties of the ligand, crystalline structure, phase purity, morphology, thermal stability, and oxidation states were illustrated using physical characterization techniques. Further, intrinsic properties of the MOF materials were studied using electrocatalytic reactions toward HER and OER in an alkaline medium. Among the synthesized MOF materials, the Co–BTC electrocatalyst showed a very low overpotential of 437 mV toward HER at a constant current density of 10 mA cm−2 in 1.0 M potassium hydroxide. The derived Tafel slope and Rct values are 115.1 mV dec−1 and 2.77 Ω cm−2, respectively. Similarly, OER studies reveal that the Co–BTC MOF showed robust activity with low overpotential of 370 mV at 10 mA cm−2. Finally, the optimal Co–BTC MOF electrode required 2.03 V of cell potential to deliver 10 mA cm−2 in a dielectrode (Co–BTC ∥ Co–BTC) electrolysis system with long-run stability. The present report reveals a new possibility for the innovation in robust HER and OER bifunctional electrocatalysts using nonprecious metallic MOF materials.

An overview of supercapacitors electrode materials based on metal organic frameworks and future perspectives

The flexible as well as wearable devices encroachment prerequisites proficient energy storage devices to satisfy their power demands. Metal ion batteries and electrochemical capacitors have attained the researcher's prodigious interest in the preset era owing to their grander energy storage features such as long cycle life, high energy, and power density. A major limitation in the practical application of metal-ion batteries in wearable devices is their inflexible and toxic nature, flammability, and low power density owing to organic nature electrolytes. In contrast, the utilization of aqueous electrolytes in supercapacitors makes them a safer substitute for wearable applications. As an emerging crystalline material, Metal-organic frameworks (MOFs) are innovative electrode materials implemented for energy storage devices because of their prominent features such as huge surface area, 3D porous and tunable structure, and permeability to extraneous entities, etc. Although the original MOFs exhibit less conductivity, this problem can be resolved by making their composites with conductive materials. Transition metal-based MOF electrodes are highly auspicious for wearable, and flexible supercapacitors due to their benign nature, low cost, high energy, and power density, as well as good stability. This review emphasizes the supercapacitors technology, their types, efficiency controlling factors for supercapacitors, new inventions in the field of non-noble metal-based MOFs electrode materials for the development of the supercapacitors by synthesizing the MOFs, MOFs derived materials, and composites by different fabrication schemes as well as the challenges associated with the utilization of MOFs and their promising solutions.

Morphologies of thienyl based bimetallic metal-organic frameworks controlled by solvents for high specific capacitance supercapacitor

Metal-organic frameworks(MOF) is a promising energy storage material, but its low electron transmission efficiency and low energy density hinder its application as a high-performance supercapacitor electrode material. Here, we show a Ni/Co bimetallic MOF electrode based on thiophene ligand with diverse morphologies from solvothermal method utilized different solvents. The results showed that the morphology of thienyl based Ni/Co MOF gradually changes from a spherical structure to a flaky structure as the degree of solvent protonation increases. Compared with other MOFs synthesized by low protonation solvent, thienyl based Ni/Co MOF with a sheet-like structure synthesized by ethanol provides more paths for electron transport between layers, and more activity for ion migration on the electrode surface site, ensuring a higher charge storage capacity. The electrochemical performance of thienyl based Ni/Co MOF as supercapacitor electrode materials in 1 M KOH was assessed, and it is found that when the current density is 1 A g−1, the maximum specific capacitance of thienyl based Ni/Co MOF(synthesized by ethanol) is 1282 F g−1, and the capacitance retention rate of asymmetric supercapacitor device assembled by thienyl based Ni/Co MOF(synthesized by ethanol) is about 73.6% even after 10,000 cycles, meaning that thienyl based Ni/Co MOF(synthesized by ethanol) is a promising electrode material for supercapacitors.

Innovative Construction of the Cobalt Metal Complex Redox Electrolyte and Octahedron Structure of the Cobalt Metal Organic Framework Electrode in the Energy Storage and Energy Conversion System

One of the most important tasks in improving supercapacitor (SC) efficiency is the quest for advanced electrode and electrolyte materials. For the first time, we propose using a metal organic frame...

Synergic effect of physically-mixed metal organic framework based electrodes as a high efficient material for supercapacitors

Porous materials have been recently used for the development of hybrid supercapacitors (HSCs) because they can facilitate rapid electron and mass transportation for energy storage purposes. Among porous materials, metal-organic frameworks (MOFs) have attracted attention as working electrodes for HSCs owing to their controllable morphology and topology, large pore and porosity size, high specific surface area, and fascinating physicochemical properties. In this study, by using an easy and cost-effective method, a copper-based MOF (Cu-MOF), a nickel-based MOF (Ni-MOF), and a cobalt-based MOF (Co-MOF) were physically combined and employed as a working electrode for supercapacitors. They were analyzed in a three-electrode system. The cyclic voltammetry (CV) measurement at the scan rate of 10 mV s−1 in 6 M KOH aqueous electrolyte showed the specific capacitances (Cs) of 316, 898, and 1823 F g−1 for Co-MOF&Cu-MOF, Ni-MOF&Co-MOF and Ni-MOF&Cu-MOF electrode, respectively. The Ni-MOF&Cu-MOF showed the highest Cs arising from the synergic effects between MOFs and the presence of multiple valence states that increases the contact area for electrolytes in the nanocomposites. This strategy can open a new window to the high performance material and facile fabrication of binary MOFs electrodes for energy storage systems.

Template-controlled in-situ growing of NiCo-MOF nanosheets on Ni foam with mixed linkers for high performance asymmetric supercapacitors

High mass loading metal–organic frameworks (MOFs) exhibit great potentials as electrode materials in energy storage, benefiting from their massive exposed reactive sites. Keeping high mass loadings while maintaining ultra-fine morphology of MOFs is very technically demanding. Herein, high mass loading binder-free NiCo-MOFs with mixed organic linkers (1,3,5-benzenetricarboxylate, BTC and p-benzenedicarboxylate, PTA) have been in-situ grown on Ni foam (NF) using Co(OH)2 as the template. The designed NiCo-(PTA)0.8(BTC)0.2 nanosheets achieved an areal capacitance of 5.84 F cm−2 (2.92 C cm−2) at a current density of 1 mA cm−2. The origin of the excellent electrochemical performances is carefully explained. The fabricated asymmetric supercapacitor (ASC) using NiCo-(PTA)0.8(BTC)0.2 nanosheets and reduced graphene oxide (rGO) as the positive and negative electrodes presented an excellent specific capacitance of 113 F g−1 at 1 A g−1. Besides, an outstanding energy density of 40 Wh kg−1 was achieved at the power density of 800 W kg−1. The assembled ASC device can retain as high as 97.7% of the original capacitance after 10,000 cycles, manifesting an excellent cycle stability. This work may provide a strategy for the preparation of high mass loading dual metal MOFs electrodes with ultra-fine morphology for high-performance supercapacitors.

Electrochemical Detection of Sarcosine and Supercapacitor Based on a New Ni–Metal Organic Framework Electrode Material

A new Ni metal organic framework based on 2,2′-Biphenyldicarboxylic, 4,4′- bipyridine as linker is prepared by hydrothermal reaction and directly used as an electrode material for supercapacitor and the detection of sarcosine. [Ni3(BIPY)3(BPDA)2(HCOO)2(H2O)2]n (Ni-1; BIPY = 4,4′-bipyridine; BPDA = 2,2′-Biphenyldicarboxylate) displays the specific capacitance of the Ni-1 are 667 F/gat 1 A/g and retention is 82% of initial capacitance at 1 A/g. The excellent electrochemical property is ascribed to the intrinsic nature of Ni-1. Furthermore, the sarcosine sensing performance of the Ni-1 electrode is evaluated in 0.1 M of NaOH solution and the electrode showed a wider range of linear response 1 × 10−4 M to 1 × 10−3 M. Thus, the results show that the Ni-1 is a potential candidate for not only sensing of sarcosine but also supercapacitor application.

Electrosorption of cadmium ions in aqueous solutions using a copper-gallate metal-organic framework

Recently, there is a recognized need for green technologies for the effective decontamination of toxic heavy metal ions in wastewater. This study demonstrates the electrochemically assisted uptake and release of cadmium ions (Cd2+) using a redox-active Cu-based metal-organic framework (MOF) electrode. Copper gallate (CuGA), which was synthesized in an aqueous solution, is a water-stable and cost-effective MOF adsorbent in which naturally abundant gallic acid is used as a linker. This work utilized copper within the CuGA structure as a redox center to attract Cd2+ by means of Cu2+/Cu+ reduction, exhibiting rapid uptake kinetics and a much higher capacity (>60 mg g−1) compared to the case without electrochemical assistance (~15 mg g−1). In addition, by applying an opposite overpotential to induce the re-oxidation of copper, the facile recovery of Cd2+ and the regeneration of the electrode were possible without regenerants. Physicochemical characterizations including XPS were conducted to investigate the chemical oxidation states and stability of the electrode after the effective electrosorption-regeneration process. This work presents the feasibility of a Cu-based MOF electrode as a reusable platform for the efficient removal of Cd2+, supporting the continued discovery and development of new Faradaic electrodes for electrochemical wastewater treatments.

High energy density supercapacitor electrode materials based on mixed metal MOF and its derived C@bimetal hydroxide embedded onto porous support

In the recent years, metal-organic frameworks (MOFs) and their derived mixed metal hydroxides/oxides structures have emerged as an engrossing category of functional materials with some unique properties such as high porosity and high specific surface area for energy storage applications. Here, a cathodic electrodeposition strategy was utilized to prepare a bimetallic NiCo metal-organic framework (NiCo-MOF) with flower-like morphology consisting of nanopetals onto Ni foam (NF) as free-standing electrode. Structural characterization revealed that Ni2+ and Co2+ metal ions are uniformly distributed on the deposited films on the nickel foam. Post-chemical treatment of NiCo-MOF/Ni foam electrode under basic condition (i.e. 4 M KOH) was concluded carbon coated hierarchical mixed hydroxide (i.e. C@Ni1-xCox(OH)2) structures onto Ni-foam with similar morphology as its pristine binary MOF. Both ready-to-use fabricated electrodes were characterized with various techniques of X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), Field-emission scanning electron microscope (FE-SEM), Energy dispersive X-ray analysis (EDAX), Energy dispersive spectroscopy (EDS) mapping and Thermogravimetric-differential scanning calorimetry (TG-DSC). Supercapacitive behaviors of pristine NiCo-MOF/NF and its derived C@NiCo-hydroxide/NF electrodes were also measured using cyclic voltammetry (CV), galvanostatic charge/discharge, and electrochemical impedance spectroscopy (EIS) measurements in 2 M KOH as electrolyte. The C@NiCo-hydroxide/NF electrode exhibited better performance as compared to pristine sacrificial binary metallic MOF electrode, which was 1825 F g–1 at a discharge current density of 1 A g–1 which still preserved 66.5% of its initial capacitance even at a high-rate load of 15 A g–1. Additionally, the C@NiCo-hydroxide/NF showed 87.6% of its capacitance at the end of 8000th cycle.

Carbonized metal-organic framework cathodes for secondary lithium-bromine batteries

Secondary lithium-bromine (Li–Br2) batteries offer cell potentials near 4 V and storage capacities over 1200 Whkg−1-LiBr. Here, we demonstrate Li–Br2 cells with two types of carbonized metal-organic frameworks (MOFs). Carbonized MIL-53(Al) electrodes show capacities of 224 mAhg−1 LiBr (at 3.4 V) and 72% capacity retention after 100 cycles, while carbonized ZIF-8 electrodes show specific capacities of 273 mAhg−1 LiBr and 88% capacity retention over 100 cycles at 1C (at 3.4 V). Surface characterization (XPS, EDS) and porosimetry indicate that the ZIF-8 derived MOF electrodes are heavily microporous with heteroatom (C–N) doping. The increased capacity and reversibility of ZIF-8 derived carbon during cyclic voltammetry and cycling measurements is ascribed to higher LiBr loadings, enhanced bromine trapping and adsorption due to the electrode microporosity and heteroatom bonding.

Carboxylated Group Effect of Graphene Oxide on Capacitance Performance of Zr-Based Metal Organic Framework Electrodes

Graphene oxide (GO) has many oxygen functional groups and high specific surface area. GO-OOH was prepared from GO by carboxylation that the hydroxyl and epoxy groups on the GO surface were converted into carboxyl groups. Zr-bdc MOF (metal organic framework of zirconium metal combined with terephthalic acid ligands modulated by acetic acid) has good thermal stability (up to 773 k) and excellent chemical stability. In order to obtain the larger pore volume and specific surface area, Zr-bdc/GO-OOH and Zr-bdc/GO were synthesized by hydrothermal reaction from the carboxylated GO (GO-OOH) with zirconium ion precursor of Zr-bdc MOF. The morphology, structure and crystallinity of the composites were investigated by Fourier transform infrared spectroscopy (FT-IR) and field emission scanning electron microscopy (FE-SEM). The electrochemical properties were characterized by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS) test.

The Different Roles of Cobalt and Manganese in Metal‐Organic Frameworks for Supercapacitors

AbstractConductive metal‐organic frameworks (MOFs) are promising electrode materials for supercapacitors (SCs) because of their tunable structures, high specific surface areas, and superior conductivity. However, it remains challenging to develop conductive MOFs for organic SCs and the role of metal ions in the electrochemical performance of MOFs is still unclear but is shown to be a key factor in determining MOFs performance. Herein, two high‐performance ultra‐thin redox conductive 2D MOFs (&gt;6000 S m−1) for SCs are prepared, and the effects of metal ions on the capacitive performance of MOF electrodes are investigated. Co2+ and Mn2+ with the same ligand provide two MOFs featuring almost the same structures and specific surface areas but show great differences in electrochemical performance except that both MOFs exhibit outstanding electrochemical performance and good cycling stability with a capacity retention of &gt;85% after 10 000 cycles. Different metal ions endow the two MOFs with different redox behaviors, conductivities, and energy levels, where Co‐MOF shows superior specific capacity compared to Mn‐MOF. This work expands the possibility of the use of MOFs in SCs and gives insight into the roles of metal ions in MOFs.

Design and Synthesis of Conductive Metal‐Organic Frameworks and Their Composites for Supercapacitors

AbstractSupercapacitors possess important prospects in power supply, owing to the characteristics of fast charging/discharging and long cycling life. As emerging materials, metal‐organic frameworks (MOFs) are the cutting‐edge electrode active materials for supercapacitors due to their good conductivity, tunable pore structure, as well as diverse composition. In this Minireview, we summarize the recent progress in MOF electrodes for supercapacitors. We focus on the synthesis of intrinsically conductive MOFs constructed from different organic linkers and adjustable metal ions, and the preparation of conductive MOF composites hybridized with conducting materials (conducting polymers and carbons). Following the discussion of both different types of conductive MOFs and their composites in supercapacitors, the challenges, and opportunities of conductive MOF electrodes for supercapacitors are further prospected at the end of this contribution, which would provide some valuable insights in facilitating the use of MOF materials in energy‐storage applications.

Unlocking the potential of metal organic frameworks for synergized specific and areal capacitances via orientation regulation

Metal organic frameworks (MOFs) with numerous potential pseudocapacitive sites are quite appealing to supercapacitors with high specific and areal capacitances. However, MOFs suffer from a low conductivity nature, resulting in a mediocre electrochemical performance. Herein, we propose a template-growth strategy of MOF to enhance both specific and areal capacitances of MOF as the electrode material for supercapacitor. As the loading mass of MOF increases from 2 to 5 mg, the specific capacitance also increases from 937 to 2387 Fg−1 (431 to 1098 Cg−1) and areal capacitance 1.87 to 11.94 Fcm−2 (0.86 to 5.49 Ccm−1). Accordingly, a hybrid MOF//AC supercapacitor can deliver a maximum energy density of 67 Wh kg−1 and a maximum power density of 6000 W kg−1. These results point to a way to fabricate MOF electrode of supercapacitor with high specific and areal capacitance, which leads them to a more practical future.