Metal-organic frameworks for supercapacitor electrodes

Abstract

Metal-organic frameworks, supercapacitor electrodes, and supercapacitors are generally provided. Some of the metal-organic frameworks described herein may be suitable for use in supercapacitor electrodes, some of the supercapacitor electrodes described herein may include the metal-organic frameworks described herein, and some of the supercapacitors described herein may include the supercapacitor electrodes described herein.

Description

[0001] This application is a divisional application of an application with an application date of September 29, 2020, application number 202080078989.1, and invention name “Metal-organic framework for supercapacitor electrodes” (PCT / US2020 / 053239, national phase entry date May 13, 2022).

[0002] Related Applications

[0003] This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 62 / 908,297, filed on September 30, 2019, and entitled “Metal-Organic Frameworks for Supercapacitor Electrodes,” the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0004] Metal-organic frameworks suitable for use as supercapacitor electrodes, supercapacitor electrodes including the metal-organic frameworks, supercapacitors, and associated articles and compositions are generally provided. Background Art

[0005] Supercapacitors are increasingly being used in more applications due to their power delivery capabilities, which are much higher than those of batteries. On the other hand, batteries excel in high energy capacity. For this reason, one of the challenges facing current technology development is the design of a battery that will exhibit both the high power density of supercapacitors and the high energy density of batteries, and therefore new electrodes with both high power density and high energy density are needed. Summary of the invention

[0006] Metal-organic frameworks, supercapacitor electrodes, and supercapacitors are generally described.

[0007] In some embodiments, a supercapacitor electrode is provided. The supercapacitor electrode includes a metal-organic framework, which includes a plurality of metal ions coordinated with a plurality of ligands. The plurality of ligands include a ligand comprising two or more sulfur donor atoms. The metal ions are coordinated with the ligands comprising the sulfur donor atoms through the sulfur donor atoms.

[0008] In some embodiments, the supercapacitor electrode comprises a metal-organic framework comprising a plurality of metal ions coordinated with a plurality of ligands. The metal-organic framework is configured to interact with a second plurality of ions so that the second plurality of ions are embedded and / or adsorbed into the metal-organic framework. The metal-organic framework is configured so that at least a portion of the metal ions undergo redox reactions during charging and / or discharging of the supercapacitor electrode.

[0009] In some embodiments, a method is provided. The method includes: performing a redox reaction in a metal-organic framework, the metal-organic framework including a plurality of metal ions coordinated with a plurality of ligands; and inserting a second plurality of ions into the metal-organic framework. The second plurality of ions and the metal-organic framework together have a neutral charge.

[0010] In some embodiments, a metal-organic framework is provided. The metal-organic framework includes multiple metal ions coordinated with multiple ligands. The metal ions include nickel ions, cobalt ions, iron ions, platinum ions and / or palladium ions. The multiple ligands include ligands containing two or more sulfur donor atoms. The metal ions are coordinated with the ligands containing sulfur donor atoms through the sulfur donor atoms. The metal-organic framework includes multiple pores with an average pore size greater than or equal to 0.3 nm and less than or equal to 1 nm.

[0011] In some embodiments, a supercapacitor is provided. The supercapacitor includes: a first electrode including a first metal-organic framework; and a second electrode including a second metal-organic framework. Each metal-organic framework includes a plurality of metal ions coordinated with a plurality of ligands. The second metal-organic framework is different from the first metal-organic framework.

[0012] Other advantages and novel features of the present invention will become apparent from the following detailed description of various non-limiting embodiments of the present invention when considered in conjunction with the accompanying drawings.In the event that this specification and documents incorporated by reference include conflicting and / or inconsistent disclosures, this specification shall prevail. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, which are schematic and are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown is generally represented by a single numeral. For clarity, not every component is labeled in every figure, nor is every component of every embodiment of the present invention shown, where an illustration is not required for one of ordinary skill in the art to understand the present invention. In the drawings:

[0014] Figure 1 One non-limiting embodiment of a metal-organic framework according to some embodiments is shown;

[0015] Figure 2 shows a non-limiting embodiment of a metal-organic framework comprising a plurality of two-dimensional sheets according to some embodiments;

[0016] Figure 3shows a non-limiting embodiment of a top view of a metal-organic framework comprising a plurality of pores according to some embodiments;

[0017] Figure 4 shows a non-limiting embodiment of a side view of such a two-dimensional sheet within a metal-organic framework according to some embodiments;

[0018] Figure 5 A non-limiting embodiment of a method of intercalating ions into a metal-organic framework between two two-dimensional sheets according to some embodiments is shown;

[0019] Figure 6 shows a non-limiting embodiment of a process for adsorbing ions into a metal-organic framework - into a plurality of pores therein - according to some embodiments;

[0020] Figure 7 A non-limiting embodiment of a supercapacitor electrode comprising a metal-organic framework according to some embodiments is shown;

[0021] Figure 8 One non-limiting embodiment of a supercapacitor including an electrode comprising a metal-organic framework according to some embodiments is shown;

[0022] Fig. 9A shows a non-limiting embodiment of the structure of a metal-organic framework according to some embodiments;

[0023] Fig. 9B shows a cyclic voltammetry (CV) curve of a Cu3BHT1 electrode in an aqueous LiCl electrolyte according to some embodiments;

[0024] Fig. 9C shows a galvanostatic charge / discharge scan of a metal-organic framework according to some embodiments;

[0025] Fig.10 shows a cyclic voltammetry curve of a metal-organic framework according to some embodiments;

[0026] Fig.11A shows an electrochemical impedance spectroscopy (EIS) Nyquist plot collected for a Cu3BHT1 electrode according to some embodiments;

[0027] Fig. 11B shows a powder X-ray diffraction pattern of Cu3BHT1 according to some embodiments;

[0028] Fig.12shows a cyclic voltammetry curve of a Cu3BHT1 electrode in the presence of an electrolyte comprising acetonitrile and LiPF6 according to some embodiments;

[0029] Fig.13A shows a schematic diagram of a Ni3BHT1 structure according to some embodiments;

[0030] Fig. 13B shows a cyclic voltammetry curve of a metal-organic framework according to some embodiments, performed at 2 mV / second;

[0031] Fig. 13C shows the specific capacitance of a metal-organic framework as a function of scan rate according to some embodiments;

[0032] FIG. 14A to FIG. 14C shows cyclic voltammetry curves of Ni3BHT1 in an electrolyte comprising acetonitrile and LiPF6 at different scan rates and potential windows according to some embodiments;

[0033] Fig.14D shows the specific capacitance of a metal-organic framework as a function of scan rate according to some embodiments;

[0034] Fig.15 shows a cyclic voltammetry curve of Ni3BHT1 in an electrolyte comprising acetonitrile and NaPF6 at a scan rate of 20 mV / sec according to some embodiments;

[0035] Fig.16 shows a cyclic voltammetry curve of Ni3BHT1 in an electrolyte comprising ethylene carbonate, dimethyl carbonate, and LiPF6 at a scan rate of 20 mV / sec according to some embodiments;

[0036] 17A to 17D shows a cyclic voltammetry curve of Ni3BHT1 in an electrolyte comprising acetonitrile and a salt according to some embodiments;

[0037] FIG. 18A to FIG. 18B shows a cyclic voltammetry curve of Ni3BHT1 according to some embodiments;

[0038] Fig.19A shows a cyclic voltammetry curve of a supercapacitor performed at 10 mV / second according to some embodiments;

[0039] Fig.19B shows a galvanostatic charge / discharge scan of a supercapacitor according to some embodiments;

[0040] Fig.19Cshows a cyclic voltammetry curve of a supercapacitor performed at 10 mV / second according to some embodiments;

[0041] Fig.19D shows the specific capacitance of a supercapacitor as a function of time when cycled between voltages of 0 V and 2.5 V at 2 A / g according to some embodiments;

[0042] Fig. 20A A schematic diagram showing a method for synthesizing a hexamercaptobenzene (benzenehexathio1) ligand according to some embodiments;

[0043] Fig. 20B A schematic diagram showing a method of synthesizing a metal-organic framework from a hexamercaptobenzene ligand and a metal chloride to form a metal-organic framework comprising a metal ion from the metal chloride coordinated by the hexamercaptobenzene ligand according to some embodiments;

[0044] Fig.21 shows the thermogravimetric response of Ni3BHT1 according to some embodiments;

[0045] Fig. 22 shows a powder X-ray diffraction pattern according to some embodiments;

[0046] Fig.23A and Fig. 23B A diagram showing a simulated structure of Ni3BHT1 according to some embodiments;

[0047] Fig.24 shows a selected area diffraction pattern of Ni3BHT1 according to some embodiments;

[0048] Fig.25A and Fig.25B shows a simulated selected area diffraction pattern of Ni3BHT1 according to some embodiments;

[0049] Fig.26 shows the structures of Ni3BHT1 and Ni3BHT2 according to some embodiments;

[0050] Fig. 27 shows a scanning electron microscope image of Ni3BHT1 according to some embodiments;

[0051] Fig.28 shows a gas adsorption isotherm of Ni3BHT1 obtained using N2 as a probe gas according to some embodiments;

[0052] Fig.29 shows variable temperature conductivity of pressed Ni3BHT1 pellets according to some embodiments;

[0053] Fig.30 shows cyclic voltammetry curves at a scan rate of 5 mV / sec in an increasing reduction potential window from 1.0 V to 1.7 V according to some embodiments;

[0054] Fig.31A and Fig.31B shows cyclic voltammetry curves of Ni3BHT1 in 1MLiPF6 / MeCN electrolyte using a 3-electrode cell setup and low scan rate according to some embodiments;

[0055] Fig.32 shows a cyclic voltammetry curve of Ni3BHT1 in 1MLiPF6 / MeCN electrolyte using a 3-electrode cell setup and a scan rate of 5 mV / sec according to some embodiments;

[0056] Fig.33 shows cyclic voltammetry curves across a potential window of 1.7 V for a scan rate range of 7 mV / sec to 28 mV / sec according to some embodiments;

[0057] Fig.34 is a graph showing current versus scan rate according to some embodiments;

[0058] Fig.35 is a graph illustrating specific discharge capacitance according to some embodiments;

[0059] Fig.36 is a graph showing capacitance retention over 8,000 cycles at a scan rate of 30 mV / sec according to some embodiments;

[0060] Fig.37 is a graph showing the cycling stability of Ni3BHT1 over 2,000 cyclic voltammetry cycles in a 3-electrode setup with a potential window of 1.7 V and a scan rate of 30 mV / sec, according to some embodiments;

[0061] Fig.38 is a plot of imaginary versus real components of impedance obtained at frequencies of 10 mHz to 200 kHz for a Ni3BHT1 electrode according to some embodiments;

[0062] Fig.39 is a graph showing a cyclic voltammetry curve at a scan rate of 5 mV / second according to some embodiments;

[0063] Fig.40 is a diagram illustrating gravimetric capacitance according to some embodiments;

[0064] Fig.41Ais a graph showing the Nyquist impedance spectrum of Ni3BHT1 according to some embodiments;

[0065] Fig.41B is a graph showing the specific capacitance of Ni3BHT1 as a function of discharge time;

[0066] Fig.42 is a graph showing powder X-ray diffraction patterns of pristine Ni3BHT1 pressed on Ni foam before and after electrochemical cycling, wherein the electrochemical cycling was performed in a 3-electrode setup at a scan rate of 30 mV / sec and the cell was held at a voltage of -1.7 V vs. OCP for five minutes before being disassembled for analysis, according to some embodiments;

[0067] Fig.43 is a graph showing the 7Li NMR spectrum of Ni3BHT1 soaked and negatively polarized in 1M LiPF6 / MeCN electrolyte according to some embodiments;

[0068] Fig.44 Figure 2 shows the electrochemical properties of Ni3HITP2 immersed and negatively polarized in 1M LiPF6 / MeCN electrolyte according to some embodiments. 7 Figure 1. Li NMR spectrum.

[0069] Fig.45 is a graph showing Ni K-edge XANES according to some embodiments;

[0070] Fig.46 is a graph showing pre-edge X-ray absorption of pristine Ni3BHT1 and negatively polarized Ni3BHT1 pellets according to some embodiments;

[0071] Fig.47 is an EXAFS graph showing k of pristine Ni3BHT1 and negatively polarized Ni3BHT1 according to some embodiments. 3 Plot of the weighted Fourier transform;

[0072] Fig.48 is an EXAFS graph showing the k of pristine Ni3BHT1 according to some embodiments. 3 Plot of the fit quality of the weighted Fourier transform;

[0073] Fig.49 is an EXAFS graph showing the k of pristine Ni3BHT1 according to some embodiments. 3 Plot of the fit quality of the weighted Fourier transform;

[0074] Fig.50is a graph showing C 1s high resolution X-ray photoelectron spectra of pristine Ni3BHT1 and negatively polarized Ni3BHT1 according to some embodiments;

[0075] Fig.51 is a graph showing Ni 2p high-resolution X-ray photoelectron spectra of pristine Ni3BHT1 and negatively polarized Ni3BHT1 according to some embodiments;

[0076] Fig.52 is a graph showing S 2p high-resolution X-ray photoelectron spectra of pristine Ni3BHT1 and negatively polarized Ni3BHT1 according to some embodiments;

[0077] Fig.53 is a graph showing a S 2p high-resolution X-ray photoelectron spectrum of pristine Ni3BHT1 according to some embodiments;

[0078] Fig.54 is a graph showing S 2p high-resolution X-ray photoelectron spectroscopy of negatively polarized Ni3BHT1 pellets according to some embodiments;

[0079] Fig.55 is the Li between the 2D layers of Ni3BHT1 according to some embodiments + Schematic diagram of ion intercalation and ion adsorption; and

[0080] Fig.56 is a schematic diagram of the synthesis of Ni3BHT1 by using a BHT ligand according to some embodiments. DETAILED DESCRIPTION

[0081] Metal-organic frameworks, supercapacitor electrodes, and supercapacitors are generally provided. Some metal-organic frameworks described herein may be suitable for use in supercapacitor electrodes, some supercapacitor electrodes described herein may include the metal-organic frameworks described herein, and some supercapacitors described herein may include the supercapacitor electrodes described herein.

[0082] In some embodiments, the metal-organic framework described herein has one or more features that enhance its suitability for use in supercapacitor electrodes. By way of example, the metal-organic framework may have one or more structural features that interact with one or more ions in a supercapacitor electrolyte in a favorable manner. For example, the metal-organic framework may include one or more structural features into which ions can be easily embedded and / or adsorbed, such as holes with a certain size into which ions can be easily adsorbed, and / or spaces with a certain size between two-dimensional sheets in the metal-organic framework into which ions can be easily embedded. The metal-organic framework with one or more such features may advantageously exhibit an increased ability to embed and / or adsorb ions from an electrolyte, thereby achieving neutralization of any charge enhancement thereon by ions from an electrolyte.

[0083] As another example, the metal-organic framework can interact with one or more ions in the supercapacitor electrolyte in a favorable manner during the redox process. For example, the metal-organic framework can include a plurality of metal ions configured to undergo redox reactions, and can be configured to balance the charge changes on the metal ions therein so that the ions embedded and / or adsorbed therein and / or deintercalated therein and / or desorbed therefrom balance the charge changes on the metal ions therein. This can make the combination of the metal-organic framework and the ions embedded therein have a neutral charge. This interaction can enhance the reversible energy storage capacity of the metal-organic framework by allowing energy to be stored on the ligands and / or metal ions of the metal-organic framework.

[0084] Some metal-organic frameworks may have one or more physical or chemical properties that enhance their performance as supercapacitor electrodes. For example, in some embodiments, the metal-organic framework described herein has a favorable high conductivity. Without wishing to be bound by any particular theory, it is believed that the ligand comprising a sulfur donor atom, such as a ligand comprising a dithiolene group, can improve the conductivity of the metal-organic framework at which it is located. It is believed that the p orbital of the sulfur donor atom has a good energy level and diffusion property, which promotes the overlap of the enhancement of the adjacent d orbital of the metal ion, and the π orbital coordination of the adjacent part of the metal ion and the ligand. Due to high conductivity, the metal-organic framework is improved to transmit electrons to the external circuit and the ability of transmitting electrons from the external circuit, which desirably reduces its internal resistance.

[0085] As another example, the metal-organic framework can have a chemical composition that allows it to electrochemically interact with one or more ions in the supercapacitor electrolyte as described above. For example, the metal-organic framework can include multiple metal ions with such a redox potential: so that a reversible redox reaction can occur during charging and discharging, wherein the charge change of the metal ion is balanced by the embedding and / or adsorption of one or more ions in the supercapacitor electrolyte and / or the deintercalation and / or desorption of one or more ions in the supercapacitor electrolyte. The coordination of multiple metal ions in the metal-organic framework with some ligands, such as ligands containing one or more sulfur donor atoms (e.g., ligands containing one or more dithioalkenyl groups), can affect the redox potential of the metal ions and thus promote this behavior.

[0086] In some embodiments, a supercapacitor is provided, comprising at least one electrode comprising a metal-organic framework. The metal-organic framework may be one of the metal-organic frameworks described herein and / or have one or more properties of the metal-organic frameworks described herein. For reasons described elsewhere herein regarding the metal-organic framework, such a supercapacitor may desirably exhibit high power delivery capability and / or energy density.

[0087] In some embodiments, the supercapacitor includes two electrodes comprising a metal-organic framework, and / or only includes an electrode comprising a metal-organic framework. Such a supercapacitor may include two electrodes, each electrode including a metal-organic framework, and the metal-organic framework in one of the electrodes is different from the metal-organic framework in the other electrode in one or more aspects. For example, the supercapacitor may include: a first electrode including a first metal-organic framework having a first electrode potential; and a second electrode including a second metal-organic framework having a second different electrode potential. The first electrode potential and the second electrode potential can together provide a desired potential difference across the entire supercapacitor. By way of example, two electrodes can together realize a supercapacitor that exhibits a potential difference across it that provides a desired power density and / or capacity.

[0088] Figure 1 A non-limiting embodiment of a metal-organic framework 100 is shown. In some embodiments, the metal-organic framework has a two-dimensional structure (e.g., Figure 2). A metal-organic framework having a two-dimensional structure can be strongly bonded together in two dimensions (e.g., by covalent bonding) and can be weakly bonded together and / or weakly interact in a third dimension (e.g., by van der Waals interactions). In other words, the interaction energy between multiple two-dimensional sheets can be less than the bond strength within multiple two-dimensional sheets. Portions of a two-dimensional structure that are strongly bonded together in two dimensions can form a two-dimensional sheet that can be macroscopically or mesoscopically extended in two dimensions and have an angstrom-like structure in the third dimension. In some embodiments, the two-dimensional structure includes structural elements that are repeated in two dimensions (e.g., in a two-dimensional sheet) but weakly ordered in a third dimension. As described elsewhere herein, the structural elements can be holes, atoms, and / or arrangements of atoms. Figure 2 One non-limiting embodiment of a metal-organic framework 102 comprising a plurality of two-dimensional sheets 202 is shown.

[0089] In some embodiments, the metal-organic frameworks described herein include a plurality of pores. Such pores can have a variety of suitable morphologies. Figure 3 A non-limiting embodiment of a top view of a metal-organic framework 104 including a plurality of pores 304 is shown. The pores in the metal-organic frameworks described herein may have a Figure 3 Some of the same features as those shown in, and / or may have Figure 3 By way of example, in some embodiments, the metal-organic framework includes Figure 3 A plurality of holes having relatively uniform size and / or spacing, such as the holes shown in FIG. Figure 3 As shown in , in some embodiments, multiple holes can be positioned relative to each other in a certain manner so as to form a lattice that repeats throughout the metal-organic framework. Figure 3 Examples of features different from those shown in FIG. 1 , in some embodiments, multiple pores occupy the same Figure 3 The volume fractions shown in FIG. 5 are different from those shown in FIG. 5 (e.g., the metal-organic framework may include Figure 3 As another example, in some embodiments, the metal-organic framework includes two different pluralities of pores that differ from each other in one or more aspects (e.g., a first plurality of pores having a first average pore size and a second plurality of pores having a second average pore size). As a third example, in some embodiments, the metal-organic framework includes a plurality of pores that are non-uniform in pore size.

[0090] It should be understood that the metal-organic framework described herein may not have porosity as measured by gas adsorption, but may include pores accessible to ions in the electrolyte, and / or may include surface pores as measured by gas adsorption but not include bulk pores as measured by gas adsorption. Similarly, some metal-organic frameworks described herein may include bulk pores that are in communication with an environmental fluid external to the metal-organic framework, and some metal-organic frameworks may include bulk pores that are not in communication with an environmental fluid external to the metal-organic framework.

[0091] In some embodiments, the metal-organic framework comprises a two-dimensional sheet comprising pores. Figure 4 A non-limiting embodiment of a side view of such a two-dimensional sheet within a metal-organic framework is shown. Figure 4 In the embodiment, the metal-organic framework 206 includes a plurality of pores 306. Figure 4 In the embodiment, a hole passes through the two-dimensional sheet from a first side to a second opposite side.

[0092] Although some of the metal-organic frameworks described herein include a Figure 4 , but some other metal-organic frameworks described herein may not contain such holes and / or may include holes of other types. For example, in some embodiments, the metal-organic framework does not have a two-dimensional sheet, but includes holes and / or includes holes in a part thereof other than the two-dimensional sheet. As another example, in some embodiments, the metal-organic framework includes holes that do not pass through the thickness of the entire metal-organic framework and / or do not pass through the thickness of one or more structural features within the metal-organic framework. As another example, the metal-organic framework may include other holes between the grains therein (e.g., grains therein randomly oriented relative to each other). Such holes can have a wide range of sizes.

[0093] The two-dimensional sheets and / or holes in the metal-organic framework described herein can have a morphology that enhances the practicality of the metal-organic framework as an electrode in a supercapacitor. For example, the two-dimensional sheets can be spaced apart from each other in a manner that allows ions to be embedded therebetween, and / or the holes in the metal-organic framework can have an average pore size that allows ions to be adsorbed therein. In some embodiments, the metal-organic framework includes both two-dimensional sheets and holes (and / or includes both two-dimensional sheets that allow ions to be embedded therebetween and holes that allow ions to be adsorbed therein).

[0094] Figure 5 A non-limiting embodiment of a method for intercalating ions into a metal-organic framework between two two-dimensional sheets is shown. Figure 5 In the embodiment, the plurality of ions 408 are embedded between two two-dimensional sheets in the plurality of two-dimensional sheets 208 . Figure 6 A similar process is shown for the adsorption of ions into a metal-organic framework, into the multiple pores therein. Figure 6 In the embodiment, a plurality of ions 410 are adsorbed into a plurality of holes 310. Figure 5 and Figure 6 As shown in , the diameter of the ion can be on the order of the spacing between the two-dimensional sheets and / or the average pore size of the pores, which is believed to facilitate the insertion and / or adsorption of ions therein. However, it should be understood that some metal-organic frameworks described herein can include pores each having an average pore size suitable for embedding more than one ion.

[0095] Ion embedding and / or adsorption into metal-organic framework can be accompanied by redox reaction.For example, in some embodiments, metal-organic framework undergoes redox reaction, and at least a portion of multiple ions embedded and / or adsorbed into metal-organic framework compensates for the charge change of metal-organic framework associated with redox reaction.As another example, in some embodiments, metal-organic framework undergoes redox reaction, and at least a portion of multiple ions de-embedded and / or desorbed from metal-organic framework compensates for the charge change of metal-organic framework associated with redox reaction.A portion of metal-organic framework undergoing redox reaction can be metal ion therein (or any other suitable portion of metal-organic framework).By way of example, at least a portion of multiple ions can be embedded and / or adsorbed, while a portion of multiple metal ions in metal-organic framework is reduced.Similarly, in some embodiments, at least a portion of multiple ions is embedded and / or adsorbed into metal-organic framework, while a portion of multiple metal ions in metal-organic framework is oxidized.Some metal-organic frameworks can be configured to have such behavior (that is, it can be configured to interact with multiple ions so that the above behavior occurs).

[0096] It is also understood that some of the metal-organic frameworks described herein can be configured to intercalate, adsorb, deintercalate, and / or desorb ions without undergoing redox reactions.

[0097] By having metal ions with redox potentials in a range suitable for undergoing redox reactions during charging and / or discharging in the metal-organic framework, redox reactions accompanying the insertion and / or adsorption of ions into the metal-organic framework and the deinsertion and / or desorption of ions from the metal-organic framework can be promoted. The redox potential of the metal ions in the metal-organic framework may be affected by one or more of the following factors: the type of metal, the oxidation state of the metal, the type of ligands to which it is coordinated, the oxidation state of the ligands to which it is coordinated, the dielectric constant of the electrolyte in the supercapacitor, the charge of the ions in the electrolyte in the supercapacitor, and the polarizability of the ions in the electrolyte in the supercapacitor.

[0098] As described elsewhere herein, some embodiments relate to supercapacitor electrodes comprising metal-organic frameworks and / or supercapacitors comprising such electrodes. Figure 7 A non-limiting embodiment of a supercapacitor electrode 512 comprising a metal-organic framework 112 is shown. Figure 7 As shown in , some supercapacitor electrodes may include a current collector (shown as Figure 7 Other supercapacitors may have no current collector and / or include Figure 7 One or more other components not shown. Figure 8 A non-limiting embodiment of a supercapacitor comprising an electrode comprising a metal-organic framework is shown. Figure 8 In the embodiment, the supercapacitor 714 includes a first electrode 514 including a metal-organic framework, a second electrode 515, and an electrolyte 814. It should be understood that the supercapacitor described herein may also include Figure 8 Other components not shown (e.g., isolator, housing, external circuit system, etc.).

[0099] Some supercapacitors described herein may be pseudocapacitors. Such a capacitor may include two electrodes, each of which undergoes faradaic charge transfer during charging and discharging. Faradaic charge transfer may include an intercalation or deintercalation process (and / or adsorption or desorption process) during discharge, and another of the intercalation and deintercalation processes (and / or adsorption or desorption processes) during charging. In other words, a pseudocapacitor may include: an electrode from which ions are deintercalated (and / or desorbed) during discharge, and into which ions are intercalated (and / or adsorbed) during charging; and another electrode from which ions are intercalated (and / or adsorbed) during discharge, and into which ions are deintercalated (and / or desorbed) during charging. Any one or both of such processes may also include redox reactions within the electrode. Such processes may also include the dissolution of an electric double layer during discharge and / or the formation of an electric double layer during charging. In some pseudocapacitors, one or both of the electrodes may include a metal-organic framework as described herein. Ions can be intercalated into and / or deintercalated from (and / or adsorbed into and / or desorbed from) a metal-organic framework.

[0100] Some supercapacitors described herein may be hybrid capacitors. Such capacitors may include an electrode that undergoes a Faraday process (e.g., an embedding or de-embedding process, an adsorption or desorption process, a redox reaction) during discharge and charge. The electrode may also exhibit a double-layer capacitance as described above for pseudocapacitors. Another electrode may not undergo a Faraday process (e.g., it may only exhibit a double-layer capacitance) during charge and discharge. In such a supercapacitor, the electrode that undergoes a Faraday process may include a metal-organic framework, and another electrode may include a material other than a metal-organic framework.

[0101] As described above, in some embodiments, the charging or discharging process includes embedding multiple ions into the metal-organic framework. This may occur during the use of a supercapacitor including a metal-organic framework for power delivery and / or may occur as a previous adjustment process. For example, some embodiments may include an adjustment process in which multiple ions are embedded into the metal-organic framework to promote other ions (for example, different types of ions) to be embedded therein during other processes to adjust it. By way of example, the process may include embedding multiple relatively large ions into the metal-organic framework in a manner that increases the spacing between the two-dimensional sheets therein. Then, such ions can be deintercalated from the metal-organic framework, after which the metal-organic framework can be permanently expanded. Subsequent processes may include embedding other ions (for example, ions with a size greater than the spacing between the two-dimensional sheets before the first multiple ions are embedded therein and less than the spacing between the two-dimensional sheets after the first multiple ions are deintercalated therein) into the metal-organic framework.

[0102] In some embodiments, a plurality of relatively large ions have a charge opposite to the plurality of ions subsequently embedded in the metal-organic framework. The process of adjusting the metal-organic framework in the presence of these ions can include first charging the metal-organic framework (e.g., positively charged) to have a first charge and then charging the metal-organic framework to have a second opposite charge (e.g., negatively charged). When the metal-organic framework is charged to have a second opposite charge, a plurality of relatively large ions can be deintercalated therefrom, and a second plurality of ions can be embedded therein.

[0103] The metal-organic framework described herein can include multiple metal ions coordinated with multiple ligands. The term "metal-organic framework" is given its ordinary meaning in the art and refers to a one-dimensional, two-dimensional or three-dimensional coordination polymer comprising a metal ion and a ligand used as an organic structural unit, wherein a portion of the metal ion is each chemically bonded to at least one ligand (e.g., a bidentate ligand, a tridentate ligand and / or a multidentate ligand). In addition to being coordinated with at least one organic structural unit, the metal ion can also be coordinated with one or more auxiliary ligands, as described in more detail herein.

[0104] The metal-organic framework described herein can have various suitable geometric shapes. In some embodiments, the metal-organic framework includes multiple metal ions, at least a portion of which is coordinated with one or more ligands. For example, in some embodiments, the metal-organic framework includes multiple metal ions, and at least a portion of the metal ions is associated with two, three or four ligands. The metal-organic framework can also include multiple ligands, at least a portion of which is coordinated with one or more metal ions. By way of example, at least a portion of the ligands in the metal-organic framework (for example, at least a portion of the non-auxiliary ligands in the metal-organic framework and / or each non-auxiliary ligand) can be coordinated with two or more metal ions. In some embodiments, the metal-organic framework includes multiple ligands, at least a portion of which is coordinated with three or four metal ions. The following are some other non-limiting examples of the morphologies that the metal ions and ligands in the metal-organic frameworks described herein can have: at least a portion of the metal ions are coordinated with at least two ligands and at least a portion of the ligands are coordinated with two metal ions, at least a portion of the metal ions are coordinated with three ligands and at least a portion of the ligands are coordinated with three metal ions, at least a portion of the metal ions are coordinated with two ligands and each ligand is coordinated with three metal ions.

[0105] The charge of the metal ions and ligands suitable for use in the metal-organic framework described herein can generally be selected as needed. For example, the metal-organic framework can include ligands with a charge of (-1), (-2), (-3), (-4), (-5) and / or (-6). As another example, the metal-organic framework can include metal ions with a charge of (+1), (+2) and / or (+3). For uncharged metal-organic frameworks, the charge of each ligand is typically balanced by the charge of the metal ions thus coordinated and adsorbed and / or embedded into any ions of the metal-organic framework.

[0106] It should be understood that the metal-organic framework described herein can include two or more types of ligands and / or two or more types of ions. When two or more types of ligands are provided, the relative amount of each type of ligand can be selected as required. Similarly, when two or more types of metal ions are provided, the relative amount of each type of metal ion can be selected as required. It should also be understood that some metal-organic frameworks described herein include a single type of ligand and / or a single type of metal ion.

[0107] The ligands containing various suitable functional groups of the coordinated metal ions can be used in the metal-organic framework described herein. Some metal-organic frameworks can include multidentate (e.g., bidentate) ligands. Such ligands can coordinate two or more metal ions and coordinate each metal ion in a multidentate manner. By way of example, the ligands for coordinating two metal ions--each metal ion is coordinated in a bidentate manner--can include two groups of two functional groups, and each group of two functional groups coordinates one metal ion. As another example, the ligands for coordinating three metal ions--each metal ion is coordinated in a bidentate manner--can include three groups of two functional groups, and each group of two functional groups coordinates one metal ion. As a third example, the ligands for coordinating four metal ions--each metal ion is coordinated in a bidentate manner--can include four groups of two functional groups, and each group of two functional groups coordinates one metal ion.

[0108] Functional groups that coordinate metal ions in a multidentate manner can adopt various suitable forms. In some embodiments, multidentate coordination is realized via vicinal functional groups (e.g., ortho functional groups). In other words, when the ligand is multidentate, the combination of functional groups configured to coordinate a single metal ion can be vicinal (e.g., ortho). In some embodiments, multidentate coordination is realized via functional groups other than vicinal functional groups (e.g., ortho functional groups, para functional groups. As described above, this means that the combination of functional groups configured to coordinate a single metal ion may not be vicinal (e.g., meta, para).

[0109] In some embodiments, the ligand is coordinated to a single metal ion by a single type of functional group. For example, the ligand may coordinate to a single metal ion by two or more identical functional groups. In some such embodiments, all metal ions coordinated by the ligand are coordinated therein by a single type of functional group.

[0110] In other embodiments, the ligand is coordinated with a single metal ion by two or more types of functional groups. For example, a metal ion can be coordinated by multiple ligands with ortho functional groups, and can also be coordinated by multiple ligands with para and / or meta functional groups. In some embodiments, a first plurality of ligands comprising an ortho functional group can coordinate multiple metal ions via an ortho functional group to form a two-dimensional sheet, and a second plurality of ligands comprising a para and / or meta functional group can coordinate multiple metal ions via a para and / or meta functional group to form a column that joins the two-dimensional sheet together.

[0111] It is also understood that some embodiments may be directed to metal-organic frameworks wherein the plurality of ligands comprises ligands comprising two or more types of functional groups and / or wherein the plurality of metal ions comprises metal ions coordinated by two or more types of functional groups.

[0112] Some metal-organic frameworks described herein can coordinate metal ions via particularly advantageous functional groups. For example, in some embodiments, the metal-organic framework coordinates metal ions via functional groups comprising sulfur donor atoms (e.g., vicinal thiolate functional groups, ortho-thiolate functional groups, dithioolefin functional groups). As another example, in some embodiments, the metal-organic framework coordinates metal ions via imine functional groups (e.g., vicinal imine functional groups, ortho-imine functional groups).

[0113] The organic core of the ligand described herein can also have various suitable structures. In some embodiments, the metal-organic framework includes a ligand with a conductive organic core. Such an organic core can include conjugated double bonds and / or aromatic moieties. For example, in some embodiments, the metal-organic framework includes a ligand comprising a fused aryl and / or heteroaryl ring. Such a ligand can have an organic core that has a rigid structure formed by a fused aryl and / or heteroaryl ring. The non-limiting examples of suitable aryl and heteroaryl rings include benzyl rings, phenylthio rings, carbazolyl rings, pyrrolyl rings, indolyl rings and furanyl rings.

[0114] An example of a suitable structure for a ligand is:

[0115]

[0116] Wherein, n is 1, 2 or 3, C represents one or more bonds formed between ring A and each ring B, and R is a functional group coordinated to a metal ion. In some embodiments, each R is -S. In some embodiments, each R is -NH. In some cases, n is 1. In some cases, n is 2. In some cases, n is 3.

[0117] Further examples of suitable structures for ligands include:

[0118]

[0119] Among them, each R 1 The same or different and are selected from hydrogen, -NO2, -R', -F, -Cl, -Br, -I, -CN, -NC, -SO3R', -SO3H, -OR', -OH, -SR', -SH, -PO3R', -PO3H, -CF3, -NR'2, -NHR' and -NH2; wherein each R' is the same or different and is an optionally substituted alkyl or an optionally substituted aryl; and wherein each R is a functional group that coordinates a metal ion. In some embodiments, at least a portion (or all) of the R' groups and the R groups are both functional groups that coordinate metal ions. In some embodiments, each R is -S. In some embodiments, each R is -NH. In some embodiments, each R 1In some embodiments, each R' is H.

[0120] Further examples of suitable structures for ligands include:

[0121]

[0122]

[0123] Among them, each R 1 The same or different and are selected from hydrogen, -NO2, -R', -F, -Cl, -Br, -I, -CN, -NC, -S03R', -S03H, -OR', -OH, -SR', -SH, -PO3R', -PO3H, -CF3, -NR'2, -NHR' and -NH2; wherein each X is the same or different and is selected from NR', O, S, Se and Te; wherein each R' is the same or different and is an optionally substituted alkyl or an optionally substituted aryl; and wherein each R is a functional group that coordinates a metal ion. In some embodiments, each R is -S. In some embodiments, each R is -NH. In some embodiments, at least a portion (or all) of the R' groups and the R groups are both functional groups that coordinate metal ions. In some embodiments, each R 1 In some embodiments, each X is the same or different and is selected from NR', O and S. In some embodiments, each X is NR'. In some embodiments, each X is O. In some embodiments, each X is S. In some embodiments, each X is Se. In some embodiments, each X is Te. In some embodiments, each R' is H.

[0124] As described elsewhere herein, the metal ions included in the metal-organic framework described herein can be monovalent, divalent and / or trivalent. Such metal ions can be transition metal ions, noble metal ions and / or post-transition metal ions. In some embodiments, each metal ion is a monovalent metal ion. A non-limiting example of a monovalent metal ion is Ag. + , Cu + and Au + In some cases, the metal-organic framework includes Cu + (e.g., as the only type of metal ion, as one of two or more types of metal ions). In some embodiments, each metal ion is a divalent metal ion. Non-limiting examples of divalent metal ions are Mg 2+ , Mn 2+ , Fe 2+ 、Co 2+ 、Ni 2+ , Cu 2+ , Pd 2+ , Pt2+ 、Ru 2+ 、Cd 2+ 、Zn 2+ , Pb 2+ , Hg 2+ 、V 2+ Cr 2+ and Ni 2+ In some cases, the metal ion is Ni 2+ (e.g., as the only type of metal ion, as one of two or more types of metal ions). In some cases, the metal ion is Cu 2+ (e.g., as the only type of metal ion, as one of two or more types of metal ions). In some embodiments, each metal ion is a trivalent metal ion. Non-limiting examples of trivalent metal ions are Fe 3+ 、V 3+ 、Ti 3+ Sc 3+ 、Al 3+ 、In 3+ , Ga 3+ , Mn 3 + 、Co 3+ and Cr 3+ In some embodiments, the metal-organic framework includes nickel ions, cobalt ions, iron ions, copper ions, platinum ions, and / or palladium ions (eg, in monovalent form, divalent form, and / or trivalent form).

[0125] As also described elsewhere herein, some metal-organic frameworks include metal ions having a redox potential suitable for undergoing an oxidation reaction during charge and / or discharge (eg, when in a supercapacitor). For example, the metal-organic framework can include multiple ions having the following redox potentials relative to a standard hydrogen electrode: greater than or equal to -3V, greater than or equal to -2.75V, greater than or equal to -2.5V, greater than or equal to -2.25V, greater than or equal to -2V, greater than or equal to -1.75V, greater than or equal to -1.5V, greater than or equal to -1.25V, greater than or equal to -1V, greater than or equal to -0.75V, greater than or equal to -0.5V, greater than or equal to -.25V, greater than or equal to 0V, greater than or equal to 0.25V, greater than or equal to 0.5V, greater than or equal to 0.75V, greater than or equal to 1V, greater than or equal to 1.25V, greater than or equal to 1.5V, greater than or equal to 1.75V, greater than or equal to 2V, greater than or equal to 2.25V, greater than or equal to 2.5V, or greater than or equal to 2.75V. In some embodiments, the metal-organic framework includes a plurality of ions having a redox potential relative to a standard hydrogen electrode of less than or equal to 3 V, less than or equal to 2.75 V, less than or equal to 2.5 V, less than or equal to 2.25 V, less than or equal to 2 V, less than or equal to 1.75 V, less than or equal to 1.5 V, less than or equal to 1.25 V, less than or equal to 1 V, less than or equal to 0.75 V, less than or equal to 0.5 V, less than or equal to 0.25 V, less than or equal to 0 V, less than or equal to -0.25 V, less than or equal to -0.5 V, less than or equal to -0.75 V, less than or equal to -1 V, less than or equal to -1.25 V, less than or equal to -1.5 V, less than or equal to -1.75 V, less than or equal to -2 V, less than or equal to -2.25 V, less than or equal to -2.5 V, or less than or equal to -2.75 V. Combinations of the above-mentioned ranges are also possible (eg, greater than or equal to -3 V and less than or equal to 3 V, greater than or equal to -3 V and less than or equal to 2 V). Other ranges are also possible.

[0126] The redox potential of the metal ion in the metal-organic framework can be determined by cyclic voltammetry for determining the redox potential of the metal-organic framework and X-ray absorption spectroscopy for confirming that the redox potential is that of the metal ion.

[0127] In some embodiments, more than one type of metal ion can be used, for example, a first type of metal ion and a second type of metal ion. The difference between the types of metal ions can be related to the element forming the metal ion and / or the valence of the metal ion. For example, some metal-organic frameworks can include two or more types of metal ions with different valences. Such types of metal ions can include metals of the same type but in different redox states (e.g., Cu + and Cu 2+ ), or may include different types of metals in different redox states (e.g., Cu + and Ni 2 + As another example, the two different types of metal ions may include different types of metals in the same redox state (e.g., Cu 2+ and Ni 2+ ). It will also be appreciated that some metal-organic frameworks may include metal ions having only a single valence and / or only a single type of metal.

[0128] When the metal-organic framework can include two or more types of metal ions with different valences, the combination of metal ion types and the relative amounts of metal ion types can generally be selected as needed. In some embodiments, the metal-organic framework includes one or more monovalent metal ions and one or more divalent metal ions. In some such embodiments, the metal-organic framework can include one or more ligands having redox activity and / or capable of accommodating different redox states of metal ions.

[0129] In some embodiments, metal-organic framework includes multiple auxiliary ligands. In this case, at least a portion of multiple metal ions therein can be associated with one or more auxiliary ligands. An auxiliary ligand can be located above and / or below the metal ion associated therewith (for example, as a top ligand). Some suitable auxiliary ligands can be charged, and other auxiliary ligands can be uncharged. Non-limiting examples of auxiliary ligands include halides (for example, chlorine, fluorine, bromine, iodine), salts (for example, nitrates, carbonates, sulfonates, etc.) and coordination solvents (for example, water, pyridine, tetrahydrofuran, diethyl ether, etc.).

[0130] Two examples of metal-organic frameworks that are considered particularly suitable for use as supercapacitor electrodes are shown below:

[0131]

[0132] Wherein, M is a metal ion. For example, M can be a transition metal ion, such as iron ion, cobalt ion, nickel ion and / or copper ion.

[0133] In some embodiments, the metal-organic framework described herein hardly includes or does not include excessive metal ions. That is, the metal-organic framework may substantially not include metal ions that are not coordinated with ligands (and / or not coordinated with ligands by functional groups configured to coordinate metal ions). Such uncoordinated metal ions are also referred to as "free metal ions" elsewhere in this article. In some embodiments, the metal-organic framework includes less than or equal to 0.5% by weight, less than or equal to 0.4% by weight, less than or equal to 0.3% by weight, less than or equal to 0.2% by weight, less than or equal to 0.1% by weight, less than or equal to 0.05% by weight, less than or equal to 0.03% by weight, less than or equal to 0.02% by weight, less than or equal to 0.01% by weight, less than or equal to 0.005% by weight, or less than or equal to 0.001% by weight of free metal ions.

[0134] The weight % of free metal ions in the metal-organic framework can be determined by X-ray photoelectron spectroscopy.

[0135] In some embodiments, the supercapacitor includes two electrodes, each electrode including one of the metal-organic frameworks shown above (e.g., a cathode including one of the metal-organic frameworks shown above, an anode including another of the metal-organic frameworks shown above). One of the electrodes may include a metal-organic framework in which a metal ion is coordinated with a ligand including a functional group containing a sulfur donor atom through a sulfur donor atom, and one of the electrodes may include a metal-organic framework in which a metal ion is coordinated with a ligand including an imine functional group through an imine functional group.

[0136] As noted above, in some embodiments, the metal-organic frameworks described herein have one or more physical properties that enhance their suitability for use in supercapacitor electrodes.

[0137] By way of example, the metal-organic framework can include a plurality of pores. The plurality of pores can have a favorable average pore size. For example, the plurality of pores can have an average pore size of greater than or equal to 0.3 nm, greater than or equal to 0.5 nm, greater than or equal to 0.75 nm, greater than or equal to 1 nm, greater than or equal to 1.25 nm, greater than or equal to 1.5 nm, greater than or equal to 1.75 nm, greater than or equal to 2 nm, greater than or equal to 2.25 nm, greater than or equal to 2.5 nm, or greater than or equal to 2.75 nm. In some embodiments, the plurality of pores have an average pore size of less than or equal to 3 nm, less than or equal to 2.75 nm, less than or equal to 2.5 nm, less than or equal to 2.25 nm, less than or equal to 2 nm, less than or equal to 1.75 nm, less than or equal to 1.5 nm, less than or equal to 1.25 nm, less than or equal to 1 nm, less than or equal to 0.75 nm, or less than or equal to 0.5 nm. Combinations of the above-mentioned ranges are also possible (eg, greater than or equal to 0.3 nm and less than or equal to 3 nm). Other ranges are also possible.

[0138] The average pore size of a plurality of pores positioned in an ordered manner can be determined by X-ray crystallography (e.g., pores positioned in a manner forming a lattice, pores forming a repeating structure in a two-dimensional sheet). The average pore size of a plurality of pores positioned in a disordered and / or random manner can be determined by Brunauer-Emmett-Teller (BET) adsorption measurements.

[0139] When the metal-organic framework includes a plurality of holes, the plurality of holes may include holes having various suitable shapes. For example, the metal-organic framework may include a two-dimensional sheet containing holes, and the holes are circular, triangular, elliptical, square, pentagonal, hexagonal and / or any other suitable shape. As another example, the metal-organic framework may include a three-dimensional hole having a shape that is spherical, oval, cylindrical and / or any other suitable shape. In some embodiments, the metal-organic framework includes holes having a shape that is close to one of the shapes mentioned above but is not the same as one of the shapes mentioned above. For example, the metal-organic framework may include a hole that can draw one of the shapes mentioned above, which overlaps with at least 80%, at least 90%, at least 95%, at least 97% or at least 99% of its area, and / or a hole that overlaps with the area of ​​one of the shapes mentioned above, at least 80%, at least 90%, at least 95%, at least 97% or at least 99% of its area.

[0140] When the metal-organic framework includes a plurality of holes, the plurality of holes may include holes surrounded by various suitable numbers of metal ions. For example, in some embodiments, the plurality of holes include holes surrounded by more than or equal to 3 metal ions, more than or equal to 4 metal ions, or more than or equal to 5 metal ions. In some embodiments, the plurality of holes include holes surrounded by less than or equal to 6 metal ions, less than or equal to 5 metal ions, or less than or equal to 4 metal ions. The combination of the above-mentioned ranges is also possible (for example, greater than or equal to 3 and less than or equal to 6). Other ranges are also possible.

[0141] When the metal-organic framework includes a plurality of holes, the plurality of holes may include holes surrounded by various suitable numbers of donor atoms (e.g., sulfur atoms). For example, in some embodiments, the plurality of holes include holes surrounded by greater than or equal to 3 donor atoms, greater than or equal to 4 donor atoms, greater than or equal to 5 donor atoms, greater than or equal to 6 donor atoms, greater than or equal to 7 donor atoms, greater than or equal to 8 donor atoms, greater than or equal to 9 donor atoms, greater than or equal to 10 donor atoms, or greater than or equal to 11 donor atoms. In some embodiments, the plurality of holes include holes surrounded by less than or equal to 12 donor atoms, less than or equal to 10 donor atoms, less than or equal to 9 donor atoms, less than or equal to 8 donor atoms, less than or equal to 7 donor atoms, less than or equal to 6 donor atoms, less than or equal to 5 donor atoms, or less than or equal to 4 donor atoms. Combinations of the above-mentioned ranges are also possible (e.g., greater than or equal to 3 and less than or equal to 12). Other ranges are also possible.

[0142] As another example of characteristics that can enhance its applicability for use in supercapacitor electrodes, the metal-organic framework may include a two-dimensional sheet having one or more desired structural features. For example, the metal-organic framework may include a two-dimensional sheet having a desired average spacing. In some embodiments, the metal-organic framework includes two-dimensional sheets spaced apart from each other at the following average spacing: greater than or equal to 0.3nm, greater than or equal to 0.4nm, or greater than or equal to 0.5nm, greater than or equal to 0.6nm, greater than or equal to 0.7nm, greater than or equal to 0.8nm, or greater than or equal to 0.9nm. In some embodiments, the metal-organic framework includes two-dimensional sheets spaced apart from each other at the following average spacing: less than or equal to 1nm, less than or equal to 0.9nm, less than or equal to 0.8nm, less than or equal to 0.7nm, less than or equal to 0.6nm, less than or equal to 0.5nm, or less than or equal to 0.4nm. Combinations of the above-mentioned ranges are also possible (e.g., greater than or equal to 0.3nm and less than or equal to 1nm). Other ranges are also possible.

[0143] The average spacing between the two-dimensional sheets can be determined by X-ray crystallography.

[0144] When the metal-organic framework includes a two-dimensional sheet, the two-dimensional sheet can be positioned relative to each other in various suitable ways. For example, some metal-organic frameworks may include two-dimensional sheets positioned relative to each other in an overlapping manner. Such metal-organic frameworks may include two-dimensional sheets with AA-type stacking. In some embodiments, the metal-organic framework includes two-dimensional sheets positioned relative to each other in a staggered manner. Such a metal-organic framework may include two-dimensional sheets with AB-type stacking and / or two-dimensional sheets that are offset to the greatest extent from each other (for example, half of the repeat distance of the primitives therein). Other positioning of the two-dimensional sheet is also possible. For example, the metal-organic framework may include two-dimensional sheets positioned relative to each other in a manner between overlapping and staggering, and / or may include two-dimensional sheets with ABC-type or other types of stacking.

[0145] As a third example of a property that may enhance its suitability for use in supercapacitor electrodes, the metal-organic framework may have a redox potential that promotes redox reactions during charging and / or discharging. For example, the metal-organic framework can have the following redox potential relative to a standard hydrogen electrode: greater than or equal to -3 V, greater than or equal to -2.7 V, greater than or equal to -2.5 V, greater than or equal to -2.3 V, greater than or equal to -2 V, greater than or equal to -1.7 V, greater than or equal to -1.5 V, greater than or equal to -1.3 V, greater than or equal to -1 V, greater than or equal to -0.7 V, greater than or equal to -0.5 V, greater than or equal to -0.3 V, greater than or equal to 0 V, greater than or equal to 0.2 V, greater than or equal to 0.5 V, greater than or equal to 0.7 V, greater than or equal to 1 V, greater than or equal to 1.3 V, greater than or equal to 1.5 V, greater than or equal to 1.7 V, greater than or equal to 2 V, greater than or equal to 2.3 V, greater than or equal to 2.5 V, or greater than or equal to 2.7 V. In some embodiments, the metal-organic framework has a redox potential relative to a standard hydrogen electrode of less than or equal to 3 V, less than or equal to 2.7 V, less than or equal to 2.5 V, less than or equal to 2.3 V, less than or equal to 2 V, less than or equal to 1.7 V, less than or equal to 1.5 V, less than or equal to 1.3 V, less than or equal to 1 V, less than or equal to 0.7 V, less than or equal to 0.5 V, less than or equal to 0.2 V, less than or equal to 0 V, less than or equal to -0.3 V, less than or equal to -0.5 V, less than or equal to -0.7 V, less than or equal to -1 V, less than or equal to -1.3 V, less than or equal to -1.5 V, less than or equal to -1.7 V, less than or equal to -2 V, less than or equal to -2.3 V, less than or equal to -2.5 V, or less than or equal to -2.7 V. Combinations of the ranges mentioned above are also possible (e.g., greater than or equal to -3V and less than or equal to 3V, greater than or equal to -2.7V and less than or equal to 1.3V, greater than or equal to -2.7V and less than or equal to 0.2V, or greater than or equal to -2V and less than or equal to 1.3V). Other ranges are also possible. In some embodiments, the supercapacitor may include two metal-organic frameworks, each metal-organic framework having a redox potential within one or more of the ranges listed above (e.g., a metal-organic framework having a redox potential greater than or equal to -2.7V and less than or equal to 0.2V, and another metal-organic framework having a redox potential greater than or equal to -2V and less than or equal to 1.3V).

[0146] The redox potential of MOFs can be determined by cyclic voltammetry.

[0147] As a fourth example of a property that may enhance their suitability for use in supercapacitor electrodes, metal-organic frameworks may have advantageously high electrical conductivity. In some embodiments, the metal-organic framework described herein has a conductivity greater than or equal to 1 S / cm, greater than or equal to 2 S / cm, greater than or equal to 5 S / cm, greater than or equal to 7 S / cm, greater than or equal to 10 S / cm, greater than or equal to 15 S / cm, greater than or equal to 20 S / cm, greater than or equal to 25 S / cm, greater than or equal to 30 S / cm, greater than or equal to 35 S / cm, greater than or equal to 40 S / cm, greater than or equal to 50 S / cm, greater than or equal to 60 S / cm, greater than or equal to 70 S / cm, greater than or equal to 80 S / cm, greater than or equal to 90 S / cm, greater than or equal to 100 S / cm, greater than or equal to 150 S / cm, greater than or equal to 200 S / cm, greater than or equal to 500 S / cm, greater than or equal to 750 S / cm, greater than or equal to 1000 S / cm, or greater than or equal to 1500 S / cm. The metal-organic framework may have a conductivity of less than or equal to 2000 S / cm, less than or equal to 1500 S / cm, less than or equal to 1000 S / cm, less than or equal to 750 S / cm, less than or equal to 500 S / cm, less than or equal to 200 S / cm, less than or equal to 150 S / cm, 100 S / cm, less than or equal to 90 S / cm, less than or equal to 80 S / cm, less than or equal to 70 S / cm, less than or equal to 60 S / cm, less than or equal to 50 S / cm, less than or equal to 40 S / cm, less than or equal to 35 S / cm, less than or equal to 30 S / cm, less than or equal to 25 S / cm, less than or equal to 20 S / cm, less than or equal to 15 S / cm, less than or equal to 10 S / cm, less than or equal to 7 S / cm, less than or equal to 5 S / cm, or less than or equal to 2 S / cm. Combinations of the above-mentioned ranges are also possible (eg, greater than or equal to 1 S / cm and less than or equal to 2000 S / cm, or greater than or equal to 1 S / cm and less than or equal to 100 S / cm). Other ranges are also possible.

[0148] The electrical conductivity of the MOFs can be determined by performing two-probe direct current measurements on 500 nm thick films of the MOFs at 25 °C.

[0149] As a fifth example of a property that may enhance its suitability for use in supercapacitor electrodes, the metal-organic framework may have an advantageously high charge mobility. The charge mobility of the metal-organic framework may be greater than or equal to 0.1 cm 2 / (V*s), greater than or equal to 0.5cm 2 / (V*s), greater than or equal to 1cm 2 / (V*s), greater than or equal to 2cm 2 / (V*s), greater than or equal to 3cm 2 / (V*s), greater than or equal to 4cm 2 / (V*s), greater than or equal to 5cm 2 / (V*s), greater than or equal to 7.5cm 2 / (V*s), greater than or equal to 10cm 2 / (V*s), greater than or equal to 20cm 2 / (V*s), greater than or equal to 30cm 2 / (V*s), greater than or equal to 40cm 2 / (V*s), greater than or equal to 50cm 2 / (V*s), greater than or equal to 75cm 2 / (V*s), greater than or equal to 100cm 2 / (V*s), greater than or equal to 250cm 2 / (V*s), greater than or equal to 500cm 2 / (V*s)cm 2 / (V*s), or greater than or equal to 750cm 2 In some embodiments, the metal-organic framework has a charge mobility less than or equal to 1000 cm 2 / (V*s), less than or equal to 750cm 2 / (V*s), less than or equal to 500cm 2 / (V*s), less than or equal to 250cm 2 / (V*s), less than or equal to 100cm 2 / (V*s), less than or equal to 75cm 2 / (V*s), less than or equal to 50cm 2 / (V*s), less than or equal to 40cm 2 / (V*s), less than or equal to 30cm 2 / (V*s), less than or equal to 20cm 2 / (V*s), less than or equal to 10cm 2 / (V*s), less than or equal to 7.5cm 2 / (V*s), less than or equal to 5cm 2 / (V*s), less than or equal to 4cm 2 / (V*s), less than or equal to 3cm 2 / (V*s), less than or equal to 2cm 2 / (V*s), less than or equal to 1cm 2 / (V*s), or less than or equal to 0.5cm2 / (V*s). Combinations of the above-mentioned ranges are also possible (e.g., greater than or equal to 0.10.5 cm 2 / (V*s) and less than or equal to 10000.5cm 2 / (V*s)). Other ranges are also possible.

[0150] The charge mobility of MOFs can be determined by performing Hall measurements on single crystals of MOFs.

[0151] Metal-organic framework described herein can be synthesized by various suitable methods.In some cases, the method for synthesizing metal-organic framework includes exposing multiple metal ions to multiple precursor ligands in the presence of an oxidant and an alkali, to form a metal-organic framework comprising at least a portion of multiple metal ions coordinated with at least a portion of multiple ligands respectively.In some embodiments, metal ion is provided as the cation of a salt, and at least one precursor ligand provided includes a functional group (for example, sulfhydryl functional group, imine functional group) configured to react with a cation.As mentioned above, the functional group can be multidentate (for example, bidentate).During the reaction process, the functional group of the precursor ligand configured to react with a cation is oxidized to the corresponding functional group (for example, the final functional group and / or imine functional group comprising a sulfur donor atom) of the coordinated metal ion in the final metal-organic framework.By way of example, for the precursor ligand comprising an o-phenylenediamine group, during the reaction process, the precursor ligand is oxidized so that each o-phenylenediamine group is converted into the o-phenylenediamine group of the coordinated metal ion.

[0152] The metal ion and the precursor ligand can be provided in any suitable amount. In some embodiments, the molar ratio of the metal ion to the precursor ligand can be based on the coordination of the metal ion to the ligand. For example, in an embodiment where the ligand coordinates to three metal ions and each metal ion is associated with two ligands, the molar ratio of the metal ion to the precursor ligand can be about 3:2. As another example, in an embodiment where the ligand coordinates to two metal ions and each metal ion is associated with one ligand, the molar ratio of the metal ion to the precursor ligand can be about 2:1. In some embodiments, the precursor ligand is provided in a slight molar excess compared to the metal ion.

[0153] As described above, the metal ions may be provided in the form of a salt. Non-limiting examples of anions that may be included in the salt include chloride, fluoride, bromide, iodide, trifluoromethanesulfonate, BF4 - PF6 - 、NO3 - 、sO4 2- and ClO4 - Salt. In some cases, the salt includes SO42- Anion.

[0154] An example of a suitable structure for a precursor ligand is:

[0155]

[0156] Wherein, n is 1, 2 or 3, C represents one or more bonds formed between ring A and each ring B, and R is a functional group configured to coordinate with a metal ion. In some embodiments, each R is -S. In some embodiments, each R is -NH. In some cases, n is 1. In some cases, n is 2. In some cases, n is 3.

[0157] Further examples of suitable structures for precursor ligands include:

[0158]

[0159] Among them, each R 1 The same or different and are selected from hydrogen, -NO2, -R', -F, -Cl, -Br, -I, -CN, -NC, -S03R', -S03H, -OR', -OH, -SR', -SH, -PO3R', -PO3H, -CF3, -NR'2, -NHR' and -NH2; wherein each R' is the same or different and is an optionally substituted alkyl or an optionally substituted aryl; and wherein each R is a functional group configured to coordinate a metal ion. In some embodiments, at least a portion (or all) of the R' groups and the R groups are both functional groups configured to coordinate a metal ion after oxidation. In some embodiments, each R is -S. In some embodiments, each R is -NH. In some embodiments, each R 1 In some embodiments, each R' is H.

[0160] Further examples of suitable structures for precursor ligands include:

[0161]

[0162]

[0163] Among them, each R 1The same or different and are selected from hydrogen, -NO2, -R', -F, -Cl, -Br, -I, -CN, -NC, -S03R', -S03H, -OR', -OH, -SR', -SH, -PO3R', -PO3H, -CF3, -NR'2, -NHR' and -NH2; wherein each X is the same or different and is selected from NR', O, S, Se and Te; wherein each R' is the same or different and is an optionally substituted alkyl or an optionally substituted aryl; and wherein each R is a functional group configured to coordinate a metal ion. In some embodiments, each R is -S. In some embodiments, each R is -NH. In some embodiments, at least a portion (or all) of the R' groups and the R groups are both functional groups configured to coordinate a metal ion after oxidation. In some embodiments, each R 1 In some embodiments, each X is the same or different and is selected from NR', O and S. In some embodiments, each X is NR'. In some embodiments, each X is O. In some embodiments, each X is S. In some embodiments, each X is Se. In some embodiments, each X is Te. In some embodiments, each R' is H.

[0164] Any suitable base may be utilized in the synthetic methods described herein. Non-limiting examples of bases include: NR"3, wherein each R" is the same or different and is hydrogen, an optionally substituted alkyl, or an optionally substituted aryl; QOH, wherein Q is a cation (e.g., a metal cation, a semimetal cation, NH4 + ); and acetate. In some embodiments, the base is NH3 or NH4OH. In some embodiments, the base is selected to have a higher pH than the group on the precursor ligand that is configured to react with the metal ion to coordinate it. Any suitable oxidant may be used. In some embodiments, the oxidant is oxygen. In some embodiments, the oxidant is a chemical oxidant. Non-limiting examples of oxidants include air, oxygen, ferricinium, nitrite, Ions, Ag 2+ 、Ag + , Fe 3+ 、MnO4 - and CrO4 - The oxidizing agent may be present in an amount suitable to aid in the oxidation of the precursor ligand. In some embodiments, the oxidizing agent is present in excess.

[0165] Any suitable solvent may be utilized in the synthetic methods described herein. Non-limiting examples of solvents include water, methanol, ethanol, propanol, benzene, p-cresol, toluene, xylene, diethyl ether, glycol, diethyl ether, petroleum ether, hexane, cyclohexane, pentane, dichloromethane, chloroform, carbon tetrachloride, dimethicone, In some embodiments, the solvent is water.

[0166] The synthetic methods described herein can be carried out at any suitable temperature. In some cases, the reaction is carried out at about room temperature (e.g., 25°C, 20°C, 20°C to 25°C, etc.). However, in some cases, the reaction is carried out at a temperature lower than or higher than room temperature. In some embodiments, the reaction is carried out at a temperature of 25°C to 100°C, 35°C to 95°C, 45°C to 85°C, or 55°C to 75°C.

[0167] Metal-organic frameworks synthesized using the methods described herein can be purified using techniques known to those of ordinary skill in the art. In some embodiments, the synthesized metal-organic framework can be washed, sometimes involving a Soxhlet extractor, boiling and / or sonication (e.g., to remove excess starting material).

[0168] The synthetic methods described herein can provide for the rapid synthesis of large quantities of metal-organic frameworks. The ability to rapidly synthesize metal-organic frameworks can facilitate the screening of known and new metal-organic frameworks to determine their suitability for use in supercapacitor electrodes.

[0169] In some cases, the metal-organic framework described herein can be formed as a film on the surface of the material. Films can be formed using techniques known to those of ordinary skill in the art. For example, films can be formed by spin-casting methods, drop casting methods, dip coating methods, roller coating methods, screen coating methods, spraying methods, screen printing methods, inkjet methods, etc. In some cases, the thickness of the film can be less than or equal to 100 microns, less than or equal to 10 microns, less than or equal to 1 micron, less than or equal to 100nm, less than or equal to 10nm, or less than or equal to 1nm. In some cases, the film can have a thickness greater than or equal to 1mm. Other ranges are also possible. The thickness of the film can be measured by a microscope.

[0170] As described above, the supercapacitor described herein may include an electrolyte, and the electrode described herein may be suitable for use with an electrolyte, and / or the metal-organic framework may be configured to interact with the electrolyte. The electrolyte is typically configured to easily allow ion transfer between the supercapacitor electrodes, thereby easily allowing ions to be embedded and / or adsorbed into one or more of the supercapacitor electrodes, and / or easily forming and / or dissolving an electric double layer. However, the electrolyte is typically configured to prevent considerable electron transfer between them. In other words, the electrolyte is typically conductive ions but not conductive. Without wishing to be bound by any particular theory, it is believed that a liquid electrolyte may be particularly suitable for use in a supercapacitor, electrode, and / or metal-organic framework described herein, and / or used with a supercapacitor, electrode, and / or metal-organic framework described herein, because it may have a particularly high ion mobility. In some embodiments, a gel electrolyte, a solid electrolyte (e.g., a polymer electrolyte) and / or a liquid salt electrolyte may also be suitable or may alternatively be suitable.

[0171] In some embodiments, the electrolyte described herein comprises a solvent. The solvent can solvate the ions from the salt dissolved therein. For example, the electrolyte can comprise water (i.e., it can be an aqueous electrolyte). In other embodiments, the electrolyte can be free of water (i.e., it can be a non-aqueous electrolyte). In addition to or instead of comprising water, the electrolyte can comprise one or more organic solvents. For example, the electrolyte can comprise acetonitrile, propylene carbonate, ethylene carbonate, dimethylformamide, diethyl carbonate, adiponitrile and / or dimethyl sulfoxide.

[0172] In some embodiments, the electrolyte described herein includes one or more salts. Salt can be dissolved in a solvent (for example, one or more of the above-mentioned solvents), or an ionic liquid can be formed (for example, the salt can be a liquid at room temperature and pressure, and can be provided without another solvent). Salt can include one or more ions configured to be embedded and / or adsorbed to the metal-organic framework described herein and / or supercapacitor electrodes. These ions can be embedded in the metal-organic framework described herein and / or supercapacitor electrodes and / or deintercalate from the metal-organic framework described herein and / or supercapacitor electrodes during supercapacitor charging and discharging (and / or adsorbed to the metal-organic framework described herein and / or supercapacitor electrodes and / or desorbed from the metal-organic framework described herein and / or supercapacitor electrodes). Such salts typically also include counter ions to these ions (in some embodiments, it is not configured to be embedded and / or is not configured to be adsorbed into the metal-organic framework described herein and / or the supercapacitor electrode, but in other embodiments, it can be configured to be embedded and / or adsorbed into the metal-organic framework described herein and / or the supercapacitor electrode during the activation process). In some embodiments, the electrolyte includes one or more salts that do not contain ions that are configured to be embedded and / or adsorbed into the metal-organic framework described herein and / or the supercapacitor electrode. Any type of salt can include ions that are transmitted between the supercapacitor electrodes during charging and discharging to form an ion flow that balances the electronic current that is also transmitted between the relevant electrodes. This ion flow can be used to maintain charge neutrality throughout the supercapacitor.

[0173] The electrolytes described herein may include salts containing ions having various suitable diameters, lengths, and / or widths. For example, the electrolyte may include salts containing ions having a diameter, length, and / or width that is smaller than the pores in the metal-organic frameworks described herein and / or smaller than the spacing between the two-dimensional sheets of the metal-organic frameworks described herein. In some embodiments, the electrolyte includes salts containing ions having a diameter, length, and / or width that is greater than or equal to Greater than or equal to Greater than or equal to Greater than or equal to Greater than or equal to Greater than or equal to Greater than or equal to Greater than or equal to Greater than or equal to Greater than or equal to or greater than or equal to In some embodiments, the electrolyte comprises a salt containing ions having a diameter, length, and / or width less than or equal to Less than or equal to Less than or equal to Less than or equal to Less than or equal to Less than or equal to Less than or equal to Less than or equal to Less than or equal to Less than or equal to or less than or equal to Combinations of the above-mentioned ranges are also possible (eg, greater than or equal to and less than or equal to ). Other ranges are also possible.

[0174] It should be understood that the electrolytes described herein may comprise ions having a diameter, length and / or width within one or more of the above ranges when in the form of bare ions (i.e., in a vacuum), and / or may comprise ions having a diameter, length and / or width within one or more of the above ranges when in the form of solvated ions (i.e., dissolved in a solvent).

[0175] The electrolytes described herein may include salts having monoatomic cations and / or polyatomic cations. Non-limiting examples of suitable monoatomic cations include H + , alkali metal cations (e.g., Li + 、Na + , K + ), alkaline earth metal cations (e.g., Mg 2+ , Ca 2+ ), post-transition metal cations (e.g., Al 3+ ). Non-limiting examples of suitable polyatomic cations include quaternary ammonium cations (e.g., ammonium cations, tetramethylammonium cations, tetraethylammonium cations, tetrabutylammonium cations, tetrapentylammonium cations, tetrahexylammonium cations, tetraheptylammonium cations, tetraoctylammonium cations, tetraethylmethylammonium cations), quaternary Cations (e.g. Cationic, Tetramethyl Cationic, tetraethyl Cationic, Tetrabutyl Cation, Tetrapentyl Cation, Tetrahexyl Cation, Tetraheptyl Cation and tetraoctyl Cation), pyrrolidine Cations (e.g., N-methyl-N-butylpyrrolidone N-Methyl-N-methoxyethyl pyrrolidine N-Methyl-N-propylpyrrolidine ) and imidazole Cations (e.g., 1-ethyl-3-methylimidazole 1-Butyl-3-methylimidazole ). As can be understood from the above, the electrolyte salt can contain cations with various suitable valences. For example, the electrolyte salt can contain monovalent cations, divalent cations, trivalent cations and / or tetravalent cations.

[0176] Similarly, the electrolytes described herein may include salts having monoatomic anions and / or polyatomic anions. Non-limiting examples of suitable monoatomic anions include halogen anions (e.g., Cl - ). Non-limiting examples of suitable polyatomic anions include SO4 2- 、NO3 - 、ClO4 - 、CO3 2- PO4 - OH - 、BF4 - PF6 - and bis(trifluoromethane)sulfonamide anions. As can be appreciated from the above discussion, the electrolyte salt may contain anions having various suitable valencies. For example, the electrolyte salt may contain monovalent anions and / or divalent anions.

[0177] As described above, the supercapacitor may include one or more electrodes comprising a metal-organic framework, and may include one or more electrodes that do not contain a metal-organic framework. Electrodes that do not contain a metal-organic framework may include various suitable materials, such as carbon (e.g., porous carbon, carbon black, graphite, graphene, carbon nanotubes), carbon nitrides, transition metal carbides, metal oxides (e.g., ruthenium oxides, molybdenum oxides, niobium oxides, manganese oxides, nickel oxides, cobalt oxides, iron oxides), metal sulfides (e.g., nickel sulfides, cobalt sulfides, molybdenum sulfides, copper sulfides), metal hydroxides (e.g., nickel hydroxides, cobalt hydroxides) and / or metal nitrides (e.g., vanadium nitrides, titanium nitrides, tungsten nitrides, molybdenum nitrides, niobium nitrides, gallium nitrides). In some embodiments, electrodes that do not contain a metal-organic framework may have a morphology in the form of a covalent organic framework or a MXene.

[0178] Electrodes that do not contain a metal-organic framework can be used as cathodes (e.g., in the case of an electrode comprising carbon, an electrode comprising a metal oxide, an electrode comprising a metal sulfide, an electrode comprising a metal hydroxide, and / or an electrode comprising a metal nitride) and / or anodes (e.g., in the case of an electrode comprising carbon and / or an electrode comprising MXene). The electrode used as a cathode typically has a potential greater than -2V (e.g., -2V to 3V) relative to the silver wire electrode, and the electrode used as an anode typically has a potential less than -2V (e.g., -3V to -2V) relative to the silver wire electrode. However, it should be understood that any of the above materials can be used as a cathode or an anode when paired with an appropriate electrode used as the other of the cathode and the anode (e.g., used as a cathode when paired with an anode having a lower potential relative to the silver wire electrode, and used as an anode when paired with a cathode having a higher potential relative to the silver wire electrode).

[0179] It should also be understood that the electrode without a metal-organic framework may be configured to embed and / or adsorb ions (e.g., in the case of a carbon-containing electrode polarized to a potential less than or equal to -2.5V or greater than or equal to 2.5V relative to the silver wire electrode), or may not be configured to embed or adsorb ions (e.g., an electrode containing carbon polarized in another manner). The electrode without a metal-organic framework may be configured to undergo redox reactions during charge and / or discharge (e.g., in the case of an electrode configured to embed and / or adsorb ions), or may not be configured to undergo redox reactions during charge and / or discharge (e.g., in the case of an electrode not configured to embed and / or adsorb ions).

[0180] In some embodiments, an electrode as described herein (e.g., an electrode comprising a metal-organic framework, an electrode without a metal-organic framework) may also include a current collector. The current collector may be a conductive material that facilitates the transfer of current to and / or from the electrode during charging and / or discharging. The current collector may be in the form of a foam, or may be in another form (e.g., a foil, a film, a disk, a matrix, a carbon cloth, a conductive flexible polymer material). Non-limiting examples of materials that may be used in the current collector include metals (e.g., nickel, gold, platinum), alloys (e.g., stainless steel), and carbon.

[0181] The supercapacitors described herein can have various suitable potential drops across them. In some embodiments, the potential drop across the supercapacitor is less than or equal to 4V, less than or equal to 3.5V, less than or equal to 3V, less than or equal to 2.5V, less than or equal to 2V, less than or equal to 1.5V, less than or equal to 1V, or less than or equal to 0.5V. In some embodiments, the potential drop across the supercapacitor is greater than or equal to 0V, greater than or equal to 0.5V, greater than or equal to 1V, greater than or equal to 1.5V, greater than or equal to 2V, greater than or equal to 2.5V, greater than or equal to 3V, or greater than or equal to 3.5V. Combinations of the above-mentioned ranges are also possible (e.g., less than or equal to 4V and greater than or equal to 0V). Other ranges are also possible.

[0182] The potential drop across the supercapacitor can be measured by using a voltmeter.

[0183] In some embodiments, the supercapacitors described herein have advantageously high weight capacitances. For example, the supercapacitors can have weight capacitances of greater than or equal to 50 F / g, greater than or equal to 75 F / g, greater than or equal to 100 F / g, greater than or equal to 125 F / g, greater than or equal to 150 F / g, greater than or equal to 200 F / g, greater than or equal to 250 F / g, greater than or equal to 300 F / g, greater than or equal to 350 F / g, greater than or equal to 400 F / g, greater than or equal to 450 F / g, greater than or equal to 500 F / g, greater than or equal to 550 F / g, greater than or equal to 600 F / g, greater than or equal to 650 F / g, or greater than or equal to 700 F / g. In some embodiments, the supercapacitor has the following weight capacitance: less than or equal to 750F / g, less than or equal to 700F / g, less than or equal to 650F / g, less than or equal to 600F / g, less than or equal to 550F / g, less than or equal to 500F / g, less than or equal to 450F / g, less than or equal to 400F / g, less than or equal to 350F / g, less than or equal to 300F / g, less than or equal to 250F / g, less than or equal to 200F / g, less than or equal to 150F / g, less than or equal to 125F / g, less than or equal to 100F / g, or less than or equal to 75F / g. Combinations of the above-mentioned ranges are also possible (e.g., greater than or equal to 50F / g and less than or equal to 750F / g, greater than or equal to 50F / g and less than or equal to 400F / g, or greater than or equal to 100F / g and less than or equal to 750F / g). Other ranges are also possible. In some embodiments, an otherwise identical supercapacitor can have a higher gravimetric capacitance when including an aqueous electrolyte than when including a non-aqueous electrolyte (e.g., an ultracapacitor including an aqueous electrolyte can have a gravimetric capacitance greater than or equal to 100 F / g and less than or equal to 750 F / g, and an otherwise identical ultracapacitor including a non-aqueous electrolyte can have a gravimetric capacitance greater than or equal to 50 F / g and less than or equal to 400 F / g).

[0184] The gravimetric capacitance of a supercapacitor can be determined by the following steps: (1) allowing the supercapacitor to stand overnight at room temperature; (2) performing a number of cyclic voltammetry cycles on it at a scan rate of 20 mV / second until a stable cyclic voltammetry curve is generated; and (3) performing a final cyclic voltammetry cycle on it at a scan rate of 1 mV / second in a 600 mV scan window; and (4) dividing the capacitance measured during the final cyclic voltammetry cycle by the weight of the supercapacitor to determine the gravimetric capacitance.

[0185] In some embodiments, the supercapacitors described herein have a favorable high power density. For example, the supercapacitors can have a power density of greater than or equal to 0.5 W / g, greater than or equal to 0.75 W / g, greater than or equal to 1 W / g, greater than or equal to 1.25 W / g, greater than or equal to 1.5 W / g, greater than or equal to 2 W / g, greater than or equal to 2.5 W / g, greater than or equal to 3 W / g, greater than or equal to 3.5 W / g, greater than or equal to 4 W / g, greater than or equal to 4.5 W / g, greater than or equal to 5 W / g, greater than or equal to 5.5 W / g, greater than or equal to 6 W / g, greater than or equal to 6.5 W / g, greater than or equal to 7 W / g, greater than or equal to 7.5 W / g, greater than or equal to 8 W / g, greater than or equal to 8.5 W / g, greater than or equal to 9 W / g, or greater than or equal to 9.5 W / g. In some embodiments, the supercapacitor has a power density of less than or equal to 10W / g, less than or equal to 9.5W / g, less than or equal to 9W / g, less than or equal to 8.5W / g, less than or equal to 8W / g, less than or equal to 7.5W / g, less than or equal to 7W / g, less than or equal to 6.5W / g, less than or equal to 6W / g, less than or equal to 5.5W / g, less than or equal to 5W / g, less than or equal to 4.5W / g, less than or equal to 4W / g, less than or equal to 3.5W / g, less than or equal to 3W / g, less than or equal to 2.5W / g, less than or equal to 2W / g, less than or equal to 1.5W / g, less than or equal to 1.25W / g, less than or equal to 1W / g, or less than or equal to 0.75W / g. Combinations of the above-mentioned ranges are also possible (e.g., greater than or equal to 0.5W / g and less than or equal to 10W / g). Other ranges are also possible.

[0186] The power density of the ultracapacitor can be determined by performing the first three steps of the method described elsewhere herein for determining gravimetric capacitance and then dividing the power measured during the final cyclic voltammetry cycle by the weight of the ultracapacitor to determine the power density.

[0187] For convenience, certain terms used in the specification, examples, and appended claims are listed here. The definitions of specific functional groups and chemical terms are described in more detail below. For purposes of the present invention, chemical elements are identified according to the Periodic Table of the Elements (CAS version), Handbook of Chemistry and Physics, 75th edition, inside cover, and specific functional groups are generally defined as described therein. In addition, the general principles of organic chemistry, as well as specific functional moieties and reactivities are described in Organic Chemistry, Thomas Sorrell, University Science Books, Sausalito: 1999.

[0188] As used herein, the term "aliphatic" includes both saturated and unsaturated, non-aromatic, straight chain (i.e., non-branched), branched, acyclic and cyclic (i.e., carbocyclic) hydrocarbons, which are optionally substituted with one or more functional groups. As will be understood by those of ordinary skill in the art, "aliphatic" is intended to include, but is not limited to, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl and cycloalkynyl moieties in this article. Therefore, as used herein, the term "alkyl" includes straight chain, branched and cyclic alkyl. Similar conventions apply to other general terms, such as "alkenyl", "alkynyl", etc. In addition, as used herein, the terms "alkyl", "alkenyl", "alkynyl", etc. include both substituted and unsubstituted groups. In certain embodiments, as used herein, "aliphatic" is used to indicate those aliphatic groups (cyclic, acyclic, substituted, unsubstituted, branched or unbranched) with 1 to 20 carbon atoms. Aliphatic substituents include, but are not limited to, any of the substituents described herein that result in the formation of a stable moiety (e.g., aliphatic, alkyl, alkenyl, alkynyl, heteroaliphatic, heterocyclic, aryl, heteroaryl, acyl, oxo, imino, thiooxo, cyano, isocyano, amino, azido, nitro, hydroxy, thiol, halo, aliphatic amino, heteroaliphatic amino, alkylamino, heteroalkylamino, arylamino, heteroarylamino, alkylaryl, arylalkyl, aliphatic oxy, heteroaliphatic oxy, alkoxy, heteroalkoxy, aryloxy, heteroaryloxy, aliphatic thio, heteroaliphatic thio, alkylthio, heteroalkylthio, arylthio, heteroarylthio, acyloxy, and the like, each of which may or may not be further substituted).

[0189] The term "alkyl" refers to a group of saturated aliphatic groups, including straight chain alkyl, branched chain alkyl, cycloalkyl (alicyclic) groups, alkyl-substituted cycloalkyl and cycloalkyl-substituted alkyl. The alkyl group may be optionally substituted, as described more fully below. Examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, 2-ethylhexyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc. "Heteroalkyl" is an alkyl group in which at least one atom is a heteroatom (e.g., oxygen, sulfur, nitrogen, phosphorus, etc.) and the remaining atoms are carbon atoms. Examples of heteroalkyl groups include, but are not limited to, alkoxy, poly(ethylene glycol)-substituted amino, alkyl-substituted amino, tetrahydrofuranyl, piperidinyl, morpholinyl, etc.

[0190] The terms "alkenyl" and "alkynyl" refer to unsaturated aliphatic groups similar to the alkyl groups described above but containing at least one double bond or triple bond, respectively. "Heteroalkenyl" and "heteroalkynyl" refer to alkenyl and alkynyl groups as described herein in which one or more atoms are heteroatoms (e.g., oxygen, nitrogen, sulfur, etc.).

[0191] The term "aryl" refers to an aromatic carbocyclic group having a single ring (e.g., phenyl), multiple rings (e.g., biphenyl), or multiple fused rings in which at least one is aromatic (e.g., 1,2,3,4-tetrahydronaphthyl, naphthyl, anthracenyl, or phenanthrenyl), all of which are optionally substituted. "Heteroaryl" is an aryl group in which at least one ring atom in the aromatic ring is a heteroatom and the remaining ring atoms are carbon atoms. Examples of heteroaryl groups include furanyl, thienyl, pyridinyl, pyrrolyl, N-lower alkylpyrrolyl, pyridinyl N-oxide, pyrimidinyl, pyrazinyl, imidazolyl, indolyl, and the like, all of which are optionally substituted.

[0192] The terms "amine" and "amino" refer to both unsubstituted and substituted amines, such as moieties that can be represented by the general formula N(R')(R") (R'"), where R', R" and R'" each independently represent a group allowed by the rules of valency.

[0193] The terms "acyl," "carboxyl," or "carbonyl" are art-recognized and may include such moieties as may be represented by the following general formula:

[0194]

[0195] Wherein, W is H, OH, O-alkyl, O-alkenyl or a salt thereof. When W is O-alkyl, the formula represents an "ester". When W is OH, the formula represents a "carboxylic acid". Generally, when the oxygen atom in the above formula is replaced by sulfur, the formula represents a "thiolcarbonyl". When W is S-alkyl, the formula represents a "thiol ester". When W is SH, the formula represents a "thiolcarboxylic acid". On the other hand, when W is an alkyl, the above formula represents a "ketone" group. When W is hydrogen, the above formula represents an "aldehyde" group.

[0196] As used herein, the term "heteroaromatic" or "heteroaryl" means a monocyclic or polycyclic heteroaromatic ring (or a group thereof) comprising carbon atom ring members and one or more heteroatom ring members (e.g., oxygen, sulfur, or nitrogen). Typically, the heteroaromatic ring has 5 to about 14 ring members, at least one of which is a heteroatom selected from oxygen, sulfur, and nitrogen. In another embodiment, the heteroaromatic ring is a 5- or 6-membered ring and may contain 1 to about 4 heteroatoms. In another embodiment, the heteroaromatic ring system has 7 to 14 ring members and may contain 1 to about 7 heteroatoms. Representative heteroaryl groups include pyridyl, furanyl, thienyl, pyrrolyl, Azolyl, imidazolyl, indolizinyl, thiazolyl, iso oxazolyl, pyrazolyl, isothiazolyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, triazolyl, pyridyl, thiadiazolyl, pyrazinyl, quinolyl, isoquinolyl, indazolyl, benzo oxazolyl, benzofuranyl, benzothiazolyl, indolizinyl, imidazopyridinyl, isothiazolyl, tetrazolyl, benzimidazolyl, benzo Azolyl, benzothiazolyl, benzothiadiazolyl, benzo oxadiazolyl, carbazolyl, indolyl, tetrahydroindolyl, azaindolyl, imidazopyridyl, quinazolinyl, purinyl, pyrrolo[2,3]pyrimidinyl, pyrazolo[3,4]pyrimidinyl, benzo(b)thienyl, etc. These heteroaryl groups may be optionally substituted with one or more substituents.

[0197] The term "substituted" is considered to include all allowed substituents of organic compounds, and "allowed" is in the context of chemical valence rules known to those of ordinary skill in the art. In some cases, "substituted" can generally refer to hydrogen being replaced by a substituent as described herein. However, "substituted" as used herein does not cover the replacement and / or change of the key functional groups of the recognition molecule, for example, so that the "substituted" functional group becomes a different functional group by substitution. For example, in this definition, "substituted phenyl" must still include a phenyl moiety and cannot be modified by substitution and become, for example, heteroaryl (e.g., pyridine). In a broad sense, allowed substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, aromatic and non-aromatic substituents of organic compounds. Illustrative substituents include, for example, those described herein. For suitable organic compounds, allowed substituents can be one or more, and can be the same or different. For the purposes of the present invention, heteroatoms such as nitrogen can have any allowed substituents of organic compounds described herein that have hydrogen substituents and / or satisfy the valence of heteroatoms. This invention is not intended to be limited in any manner by the permissible substituents of organic compounds.

[0198] Examples of substituents include, but are not limited to, alkyl, aryl, aralkyl, cycloalkyl, heterocycloalkyl, hydroxy, alkoxy, aryloxy, perhaloalkoxy, aralkyloxy, heteroaryl, heteroaryloxy, heteroarylalkyl, heteroaralkyloxy, azido, amino, halogen, alkylthio, oxo, acyl, acylalkyl, carboxyester, carboxy, amido, nitro, acyloxy, aminoalkyl, alkylaminoaryl, alkylaryl, alkylaminoalkyl, alkoxyaryl, arylamino, aralkylamino, alkylsulfonyl, amidoalkylaryl, amidoaryl, hydroxyalkyl, haloalkyl, alkylaminoalkylcarboxy, aminoamidoalkyl, alkoxyalkyl, perhaloalkyl, arylalkoxyalkyl, and the like.

[0199] Example 1

[0200] This embodiment describes a new lithium ion high capacitance and low equivalent series resistance (ESR) electrode using a highly conductive and porous two-dimensional metal-organic framework (2D-MOF). In the two-dimensional metal-organic framework, charges are stored in the pseudo-circular holes of the framework by inserting lithium ions into the 2D-MOF. The electrode has a capacitance of 475F / g in an aqueous LiCl electrolyte and has a measured ESR of 0.17 ohms. It is believed that this performance is related to the structure and chemical composition of the 2D-MOF, which includes a pore size small enough for effective lithium ion insertion and a conductivity high enough to provide low ESR.

[0201] The conductive 2D-MOF used in this example is copper hexamercaptophenyl (CU3BHT1), in which copper ions are coordinated to hexamercaptophenyl moieties. 2 The BET surface area of ​​this 2D-MOF is on the order of 1 / g, but it is believed that the true surface area of ​​this 2D-MOF is actually larger than this value. CU3BHT1 includes quasi-triangular pores surrounded by copper and sulfur atoms (see Fig. 9A ), which is considered too small to be penetrated by the gas probes (e.g., N2) employed during BET measurements but large enough to be valuable for supercapacitor applications.

[0202] Thus, this embodiment contemplates the use of CU3BHT1 and structural analogs having one or more of the following features: (1) conductive ligands, such as conjugated aromatic ligands; (2) metal ions; and (3) pores having diameters suitable for lithium or other ion insertion, such as greater than or equal to 0.3 nm and less than or equal to 0.33 nm. Also contemplated are 2D-MOFs suitable for embedding and / or adsorbing other alkali ions and / or alkaline earth metal ions, as well as the use of aqueous and non-aqueous solvents to dissolve such ions.

[0203] Fig. 9B Cyclic voltammetry (CV) curves of CU3BHT1 electrode in aqueous LiCl electrolyte are shown. These curves show two clear events in the 1 mV / sec scan, one at -0.66V and the other at -0.35V. Without wishing to be bound by any particular theory, it is believed that these events are related to the interaction of lithium ions with the 2D-MOF, and that this interaction contributes to the high measured capacitance values. These same interactions can be seen in Fig. 9C The highest capacitance recorded for the CU3BHT1 electrode was 475 F / g at a cycle rate of 1 mV / sec. The electrode also exhibited good capacitance retention, with capacitance values ​​greater than 100 F / g ( Fig. 9B The stability of the capacitance was confirmed when constant current charging and discharging was performed, with the CU3BHT1 electrode showing 90% retention of the initial capacitance value after 5000 charge / discharge cycles at a current density of 5 A / g.

[0204] Note that the measured capacitance can vary with the ramp rate: Fig.10 More data obtained in the presence of NaCl solution at 10 mV / sec are shown, where the CU3BHT1 electrode shows a capacitance of 290 F / g.

[0205] Further experiments were performed in which electrochemical impedance spectroscopy (EIS) Nyquist plots were collected for the CU3BHT1 electrode. These plots were collected over a 20 minute period by performing the following steps: (1) applying a voltage of -0.1 V to the electrode; (2) decreasing the voltage applied to the electrode to -0.6 V; and (3) increasing the voltage applied to the electrode back to -0.1 V ( Fig.11A ). The Nyquist plot of an electrode consists of three semicircles: one at high frequency, one at medium frequency, and one at low frequency.

[0206] During the voltage sweep, the position of the ESR on the high frequency end of the minimum semicircle moves upward from 0.15 ohms at -0.2 V to 0.20 ohms at -0.6 V. Upon returning to -0.2 V, the ESR moves back to 0.15 ohms.

[0207] During the same voltage sweep described above, the radius of the intermediate frequency semicircle varied from 1.4 ohms to 1.7 ohms, exhibiting a change believed to be related to a change in charge transfer resistance.

[0208] The low frequency semicircle shows the greatest change over the voltage sweep: it changes from 20 ohms at -0.2 V to 675 ohms at -0.6 V. Fig.11A It is obvious that the shape of the low-frequency semicircle changes fastest between -0.4 V and -0.2 V, and changes less rapidly in the region around -0.6 V. It is believed that the low-frequency semicircle is related to the electrolyte resistivity: it is believed that increasing Li + The introduction of ions into the electrode increases its resistance, leading to increased ESR and charge transfer resistance. It is also believed that due to the Li + Ions are inserted into the electrode, and the free Li in the electrolyte during charging + The amount of ions decreases, thereby increasing the resistivity of the electrolyte.

[0209] The powder X-ray diffraction pattern of CU3BHT1 taken at the voltage where the peak in the CV trace appears does not show any changes in its unit cell, which means that Li + Insertion and removal therefrom do not subject the material to mechanical stress ( Fig. 11B ). Advantageously, this also means that charging and discharging of the CU3BHT1 can be performed without mechanical stress.

[0210] Fig.12 The cyclic voltammetry curve of the CU3BHT1 electrode in the presence of an electrolyte containing acetonitrile and LiPF6 is shown. The cyclic voltammetry curve was performed at 20mV / sec and showed a capacitance of 254F / g in the electrochemical window of 0.2V to -1.2V for the CU3BHT1 electrode compared to silver wire. Fig.12It is shown that the CU3BHT1 electrode can also be suitable for use in supercapacitors containing non-aqueous and / or organic electrolytes.

[0211] CU3BHT1 electrodes were made by pressing the synthesized 2D-MOF to form pellets. Either Ni foam or gold current collectors were used to support the CU3BHT1 electrodes, both of which caused the electrodes to display the same CV shape during the above tests. The absolute voltage values ​​of the CV peaks shifted slightly as the other test conditions changed (e.g., when moving from measurements performed in a beaker to measurements performed on a stainless steel cell), but these shifts are believed to be due to the different relative masses of the 2D-MOF electrode and the carbon counter electrode and the different cell geometries under these different test conditions. For a given experimental setup, the results were consistent across several different cells that were tested over a period of several weeks and formed from different batches of CU3BHT1.

[0212] Example 2

[0213] This example describes the performance of an electrode comprising nickel hexamercaptophenyl (Ni3BHT1) metal-organic framework.

[0214] Fig.13A A schematic diagram of the Ni3BHT1 structure is shown, which forms a two-dimensional sheet including pores.

[0215] Ni3BHT1 2D-MOF shows favorable capacitance values ​​in the presence of aqueous electrolytes including LiCl and / or NaCl, such as FIG. 13B to FIG. 13C As shown in (showing the cyclic voltammetry curve performed at 2 mV / sec and the specific capacitance as a function of the scan rate, respectively). It is also conceivable that Ni3BHT12D-MOF can be used in supercapacitors including aqueous electrolytes containing one or more of the following ions: Mg 2+ , K + 、Al3 + 、SO4 2- 、CO3 - and NO3 - .

[0216] Ni3BHT1 2D-MOF also shows favorable capacitance values ​​in the presence of non-aqueous electrolytes, examples of which are detailed below.

[0217] FIG. 14A to FIG. 14C Shown are the cyclic voltammetry curves of Ni3BHT1 in an electrolyte containing acetonitrile and LiPF6 at different scan rates and potential windows. Fig.14DThe specific capacitance extracted from this data as a function of scan rate is shown. Note that the cyclic voltammetry curve does not show any obvious redox peaks, and thus lithium ion intercalation into the Ni3BHT1 electrode can occur without a redox reaction between the lithium ions and the Ni3BHT1 2D-MOF.

[0218] Fig.15 Cyclic voltammetry curves of Ni3BHT1 in an electrolyte containing acetonitrile and NaPF6 at a scan rate of 20 mV / s are shown, demonstrating the suitability of this 2D-MOF for use in supercapacitor electrodes constructed to intercalate sodium ions.

[0219] Fig.16 Cyclic voltammetry curves of Ni3BHT1 in electrolytes containing ethylene carbonate, dimethyl carbonate, and LiPF6 at a scan rate of 20 mV / s are shown, demonstrating the applicability of this 2D-MOF for use in supercapacitor electrodes including other types of non-aqueous electrolytes.

[0220] FIG. 17A to FIG. 17D Cyclic voltammetry curves of Ni3BHT1 in an electrolyte comprising acetonitrile and one of various salts are shown. These cyclic voltammetry curves were obtained at 10 mV / second and demonstrate the ability of Ni3BHT1 to intercalate larger cations (e.g., those typically found in ionic liquids) in addition to the above-mentioned alkali metal cations. Cyclic voltammetry curves of Ni3BHT1 in the presence of LiPF6 ( Fig.17A ) has a nearly rectangular shape, which indicates that ions are embedded therein. + 、TEA + and TBA + The cyclic voltammetry curve of Ni3BHT1 in the presence of a salt of the cation has a pointed shape instead.

[0221] Without wishing to be bound by any particular theory, it is believed that the cyclic voltammetry curves having a shape including low current intensity at a larger polarization (-1V to -2V) (e.g., having a pointed shape at a larger polarization, such as the shapes shown in Figures EAB to EAD) indicate that the 2D-MOF has some surface area that is inaccessible to larger ions. For Ni3BHT1, it is believed that larger ions may not be able to penetrate between the two-dimensional sheets therein. The spacing between the two-dimensional sheets in Ni3BHT1 is about 0.35nm, which is larger than that of Li + and Na + cation diameter, but smaller than EMIM + 、TEA + and TBA + The diameter of the cation (EMIM + 、TEA+ and TBA + The diameters of the cations are 0.7nm, 0.68nm and 0.82nm respectively).

[0222] FIG. 18A to FIG. 18B The cyclic voltammetry curve of Ni3BHT1 over a potential window including two parts, positive and negative, is shown relative to a silver wire reference electrode. Three cycles were performed at 20 mV / sec: a first cycle in which a negative potential was applied to the 2D-MOF, a second cycle in which a positive potential was applied to the 2D-MOF, and then a third cycle identical to the first cycle.

[0223] The cyclic voltammetry curve from the first cycle has a pointed shape as described above. However, the cyclic voltammetry curve from the third cycle has a more rectangular shape. It is believed that the application of positive charge to the 2D-MOF during the second cycle causes anions from the salt dissolved in the electrolyte to be embedded in the 2D-MOF, and this embedding increases the average spacing between the two-dimensional sheets therein. It is also believed that this allows for increased embedding of larger cations into the 2D-MOF during the third cycle.

[0224] Example 3

[0225] This example describes the performance of a supercapacitor comprising an anode and a cathode, the anode comprising a Fig.13A The supercapacitor further comprises an electrolyte comprising 1 M LiPF6 in acetonitrile.

[0226] Fig.19A Cyclic voltammetry curves of supercapacitors performed at 10 mV / sec are shown. These curves show a stable rectangular shape at the voltage windows of 2V, 2.2V and 2.5V.

[0227] Fig.19B The galvanostatic charge / discharge scans of the supercapacitor are shown. These galvanostatic charge / discharge scans were performed at a current of 2A / g and cycled between voltages of 0V-2V, 0V-2.2V, and 0V-2.5V.

[0228] Fig.19C Cyclic voltammetry curves of the supercapacitor performed at 10 mV / sec are shown. These curves indicate reversibility in a voltage window up to 3 V. However, cycling in a voltage window exceeding 2.5 V does result in the presence of a distorted shape.

[0229] Fig.19D Shown is the specific capacitance of the supercapacitor as a function of time when cycled between voltages of 0 V and 2.5 V at 2 A / g.

[0230] Example 4

[0231] This example describes a method for synthesizing a metal-organic framework having a structure suitable for use as an electrode of a supercapacitor.

[0232] Fig. 20A A schematic diagram showing a method for synthesizing a hexamercaptobenzene ligand is shown.

[0233] Fig. 20B A schematic diagram showing a method for synthesizing a metal-organic framework from a hexamercaptobenzene ligand and a metal chloride to form a metal-organic framework comprising metal ions from the metal chloride coordinated by the hexamercaptobenzene ligand is shown.

[0234] Example 5

[0235] Supercapacitors (SCs) have emerged as reliable and fast-charging electrochemical energy storage devices that provide high power density. However, their use is still limited by their relatively low energy density. This example describes a new non-porous CP, (Ni3(benzenethiolate hexakis)(Ni3BHT1), which exhibits a high conductivity of over 500 S / m. When used as an electrode of a supercapacitor, Ni3BHT1 provides an excellent specific capacitance of 245 F / g and 426 F / cm in a non-aqueous electrolyte. 3 The structural and electrochemical studies relate the good performance to the pseudocapacitive insertion of Li + ions between the 2D layers of Ni3BHT1.

[0236] Synthesis and Structural Characterization

[0237] Microcrystalline samples of Ni3BHT1 were obtained by reacting hexamercaptobenzene C6S6H6 with NiCl2·6H2O in degassed methanol for 24 hours at room temperature under anaerobic conditions. After separation from the mother liquor, Ni3BHT1 showed no weight loss below 200 °C and its conductivity was maintained in air for at least 6 months ( Fig.21 ). The powder X-ray diffraction (PXRD) pattern of freshly synthesized Ni3BHT1 did not match the powder X-ray diffraction (PXRD) pattern of Ni3(BHT)2 and instead was similar to the powder X-ray diffraction (PXRD) pattern of Cu3BHT1 ( Fig. 22 ). Additional analysis by selected area electron diffraction (SAED) revealed unit cell parameters α = 90°, β = 99.7° and γ = 90° (Figs. 23 to Fig.26), these unit cell parameters are indeed similar to those of Cu3BHT1. Taken together, the PXRD and SAED data indicate that Ni3BHT1 is a new phase closely similar to Cu3BHT1, in which the 2D layer consists of square planar Ni atoms bonded to four S atoms in a square planar coordination. 2+ ions and BHT ligands surrounded by six Ni atoms. These form a more open, hexagonal honeycomb structure ( Fig.26 ) in contrast to the dense arrangement of the 20% MgO2O3O4 ...

[0238] The bulk physical properties of Ni3BHT1 were investigated using scanning electron microscopy (SEM), N2 gas adsorption analysis, and van der Pauw conductivity measurements. SEM images revealed rod-like structures with lengths greater than 100 nm and diameters of tens of nanometers ( Fig. 27 ). N2 adsorption analysis determined that about 25 m 2 / g low Brunauer-Emmett-Teller (BET) SSA ( Fig.28 ), consistent with the expected nonporous nature of Ni3BHT1. The variable temperature conductivity of the pressed Ni3BHT1 pellets shows an excellent conductivity of about 500 S / m at 298 K and a steady decrease with decreasing temperature, as has been observed for several other bulk phases of 2D MOFs ( Fig.29 ). Overall, the 2D layered structure of Ni3BHT1 and its high electrical conductivity and thermal stability provide support to evaluate its performance in supercapacitors. Electrochemical analysis was performed using 1M lithium hexafluorophosphate (LiPF6) / MeCN electrolyte, which is believed to have a small enough cation size to potentially intercalate between Ni3BHT1 layers.

[0239] Electrochemical performance in supercapacitors

[0240] Cyclic voltammetry (CV) of Ni3BHT1 powder pressed on Ni foam was performed in a three-electrode cell using sufficiently large porous carbon as the counter electrode and Ag wire as the quasi-reference. The CV curves obtained in increasingly larger potential windows up to 1.7 V showed distorted rectangular curves without clear Faradaic processes ( Fig.30 ). Even when the scan rate was reduced to as low as 0.5 mV / sec ( Fig.31A and Fig.31B), a stable rectangular voltammogram was also observed, but scanning beyond -1.7 V vs. open circuit potential (OCP) resulted in a rapid decay of the current after multiple cycles ( Fig.32 ). In total, the CV responses indicate the capacitive charge storage process in Ni3BHT1 and also determine a safe operating potential window of 1.7 V. Ni3BHT1 exhibited 245 F / g and 426 F / cm at a scan rate of 3 mV / s. 3 The high specific capacitance of Ni3BHT1 is very high for a material with a surface area as low as that of Ni3BHT1. In fact, given its low surface area, it is believed that the large specific capacitance of Ni3BHT1 cannot be attributed to ideal double-layer charge storage. An alternative mechanism is one based on embedded pseudocapacitance.

[0241] One way to interrogate the mechanism that produces the high capacitance of Ni3BHT1 is through electrochemical kinetic studies that evaluate the ion adsorption properties on the electrode. The current is plotted as i(V) / v over a series of scan rates at 3 different potentials. 1 / 2 Vs.v 1 / 2 To analyze the capacitance contribution in Ni3BHT1 ( Figure 33 to Figure 34 ). The slopes of these curves indicate a major capacitance contribution of 80%, 78%, and 76% at -1.2 V, -1.5 V, and -1.7 V vs. OCP, respectively, indicating controlled surface ion adsorption in Ni3BHT1. The specific capacitance calculated from these curves reaches high values ​​of 195 F / g, 124 F / g, and 85 F / g at scan rates of 7 mV / sec, 14 mV / sec, and 28 mV / sec, respectively ( Fig.35 Long-term cycling studies of Ni3BHT1 in different potential windows at a fast scan rate of 30 mV / s (discharge in 56 s) indicated more than 80% retention after 8,000 cycles ( Fig.36 ), but cycling in the widest window at 1.7 V reduces the capacitance retention to 70% after 2000 cycles ( Fig.37 ).

[0242] Electrochemical impedance spectroscopy (EIS) was recorded at OCP at various negative polarizations to analyze the ion transport in Ni3BHT1 under dynamic conditions ( Fig.38 ). The EIS curves show an extended 45° Warburg region in the mid-frequency region and a strong deviation from the vertical line in the lower frequency region, consistent with non-ideal capacitive behavior typically associated with limited ion transport in electrode materials. In addition, a closer look at the increased high-frequency region yields a semicircle diameter with stronger polarization (inset, Fig.38 ), indicating that the typical charge transfer mechanism of pseudocapacitive electrodes may be operative.

[0243] Effect of Electrolyte Ion Size

[0244] Next, experiments were performed to determine whether Ni3BHT1 displays intercalation-based pseudocapacitance. For this purpose, electrolyte salts with cations and anions of various sizes were employed: tetraethylammonium hexafluorophosphate (NEt4PF6), tetraethylammonium tetrafluoroborate (NEt4BF4), and tetrabutylammonium tetrafluoroborate (NBu4BF4). Comparison of the CV curves obtained with these electrolytes showed that the 3D-type Ni3BHT1 has a 3D-type intercalation-based pseudocapacitance of 1.17kV. + The much lower current of tetraalkylammonium (TAA) cation ( Fig.39 ), and Li + The correspondingly lower capacitance of about 30 F / g is compared to 227 F / g ( Fig.40 ). Changing the anion and comparing NEt4PF6 to NEt4BF4 gives very similar CVs ( Fig.39 ), indicating that any difference in behavior is caused by the cations and that the ion adsorption process is accordingly mainly driven by the cations. The CV in the TAA electrolyte further shows an almost flat shape when scanning cathodically relative to the OCP, where the current approaches zero. It is believed that the observed ion screening behavior can be attributed to its ordered 2D layered structure, in which only ions smaller than the interlayer spacing are embedded. In fact, it is believed that Li + ions are small enough to embed, and their response in the low-frequency region of the EIS deviates significantly from the ideal vertical line and is consistent with the larger TAA + The response of cations is different, TAA + The cations were thought to be too large to be embedded ( Fig.41A ).

[0245] Overall, the electrochemical studies support the conclusion that ion adsorption in Ni3BHT1 is affected by the size of the cations and that the insertion of ions into the 2D layer affects the overall capacitance. Ni3BHT1 shows a steady decrease in performance when discharged in less than 3 minutes ( Fig.41B ). This, together with the significant deviation from the ideal vertical line at low EIS frequencies expected for pseudocapacitive materials, indicates hindered ion transport at high discharge rates.

[0246] Characterization of electrode technology

[0247] The structural and compositional evolution of Ni3BHT1 under potential bias was investigated using various ex situ X-ray and solid-state nuclear magnetic resonance (SSNMR) spectroscopy techniques. The PXRD patterns of Ni3BHT1 electrodes cycled and negatively polarized in 1M LiPF6 / MeCN indicate good preservation of crystallinity, highlighting the stability of Ni3BHT1 under electrochemical conditions ( Fig.42 ).

[0248] The Ni3BHT1 samples prepared as immersed in electrolyte or as negatively polarized in SC were compared. 7 Li SSNMR spectroscopy to identify the period of ion adsorption under polarization 7 Different chemical environments of Li. To provide a point of comparison, similar experiments were performed using Ni3HITP2 (HITP = 2,3,6,7,10,11-hexaminintriphenylene), a 2D porous MOF believed to adsorb ions in its micropores. 7 The Li SSNMR spectra show a strong isotropic peak at about 0 ppm for both materials under all conditions ( Fig.43 and Fig.44 ). These peaks are assigned to Li associated with the surface of particles or pores. + ions. One notable difference is the observed asymmetry of the polarized Ni3BHT1 sample at about 3 ppm, which is even more pronounced at its satellite peaks at about -70 ppm and -73 ppm (inset, Fig.43 ). Despite having similar isotropic chemical shifts due to the small diamagnetic chemical shift range of lithium, the different chemical shifts in the polarized Ni3BHT1 sample are considered to indicate different ions with different nuclear quadrupole coupling interactions. 7 Li chemical environment. Because Ni3HITP2 exhibits micropores and thus allows double-layer ion adsorption, its 7 The Li SSNMR spectrum shows a single Gaussian-like resonance ( Fig.44 ). The other 7 The Li adsorption sites are believed to be derived from the Li embedded between the 2D sheets. + Ion production is consistent with electrochemical data.

[0249] It is believed that X-ray absorption spectroscopy (XAS) indicates that the pseudocapacitive behavior of Ni3BHT1 is not Ni-based. X-ray absorption near-edge spectroscopy (XANES) at the Ni-K edge reveals edge and front energies of 8.346 keV and 8.334 keV for both pristine and polarized Ni3BHT1, respectively, which is believed to indicate that the 2+ oxidation state of Ni continues to exist during supercapacitor operation ( Fig.45 and Fig.46 ). In addition, analysis of the local coordination around Ni from X-ray absorption fine structure (EXAFS) revealed essentially the same Ni coordination number of 4 (±0.4) and 3.7 (±0.4) before and after polarization ( Figure 47 to Figure 48 ). Similarly, the Ni-S bond length in Ni3BHT1 remains largely unchanged but changes from arrive The slight decrease in indicates an increase in the electron density on the S atom. These observations suggest that the redox process is not metal-based but rather centered on the ligand. Indeed, high-resolution X-ray photoelectron spectroscopy (XPS) shows that the C 1s and Ni 2p peaks are not affected by polarization, and the only observable change is in the case of the S2p peak ( Figure 50 to Figure 52 Specifically, the S signal is deconvolved into a signal with 2 p1 / 2 and 2 p3 / 2 The various chemical compositions of the doublet structure reveal the loss of SH components and the appearance of S-Li components upon polarization, indicating that the Li associated with the electronegative S site + The reduction and subsequent embedding ( Figure 53 to Figure 54 ). Notably, the observed redox process is believed to distinguish Ni3BHT1 from other transition metal-based pseudocapacitive materials where multiple oxidation states of the metal ion (Ru, Nb, or Mo) are entered during intercalation. Unfortunately, the extended conjugated structure on the metal-organic framework makes it infeasible to determine the exact change in oxidation state of the ligand. However, the high specific capacitance and large reduction potential window via intercalation pseudocapacitance identify Ni3BHT1 as a promising negative electrode toward the fabrication of high-voltage asymmetric supercapacitors.

[0250] in conclusion

[0251] In summary, it was demonstrated that despite its lack of porosity, Ni3BHT1 is a promising electrode material for supercapacitors, providing a high specific capacitance of 245 F / g in a large reduction potential window of 1.7 V. Extensive electrochemical analysis supports the inference that an intercalation-based ion adsorption mechanism enables this high capacitance in Ni3BHT1. Fig.55 A schematic diagram of the process is shown in FIG.

[0252] Materials and methods

[0253] NiCl2·6H2O was purchased from Sigma-Aldrich and used without further purification. Methanol and MeCN were purchased from VWR and collected from an alumina column solvent purification system. Methanol was degassed overnight using internal N2 before Ni3BHT1 synthesis. All electrolytic salts - LiPF6 and tetraalkylammonium salts - were purchased from Sigma-Aldrich or Beantown Chemicals and used without further purification. Activated carbon was prepared as a thin film by repeatedly kneading and rolling a slurry of a mixture of activated carbon, acetylene black and PTFE solution in a ratio of 8:1:1 with ethanol, respectively. The prepared film was dried at 120°C overnight before use in supercapacitors.

[0254] Synthesis of Ni3BHT1

[0255] First, 132 mg (0.555 mmol) of NiCl2·6H2O was dissolved in 100 mL of degassed methanol under a nitrogen atmosphere. BHT powder (50 mg, 0.185 mmol) was slowly added to the solution over 30 minutes, and the mixture was then allowed to react at room temperature for 24 hours. The resulting powder was filtered and washed twice with water and ethanol each, and dried at 100°C under dynamic vacuum for 12 hours. Yield: 73 mg, 90%.

[0256] Elemental analysis was performed by Robertson Microlit Laboratories, New Jersey, USA, using combustion and titration techniques. The data obtained were fitted using ethanol and water as solvent residues in the material. Expected C: 19.43%, S: 44.41% and H: 1.61%. Observed C: 19.54%, S: 44.66% and H: 1.56%.

[0257] Fig.56 The synthesis of Ni3BHT1 is schematically depicted.

[0258] Conductivity

[0259] The conductivity of Ni3BHT1 was measured by the four-point Van der Pauw method at 3.0 tons force / cm 2 The measurements were performed on pressed pellets with a diameter of 7 mm. A Keithley 2450 source meter was used as the current source and a Keithley 2182A unit was used as the voltmeter.

[0260] Electrochemical characterization and analysis

[0261] All electrochemical measurements were performed using a Biologic VSP-300 potentiostat. EIS measurements were performed using multiple sinusoidal signals with an amplitude of 10 mV over a large frequency range of 10 mHz to 200 kHz. The specific gravimetric capacitance (C) was calculated from the discharge sequence of the three-electrode CV curve using the following equation: g ): Cg=((∫I.dV) / (mvdV)),

[0262] Where m = the mass of the working electrode, dV = the discharge potential window, and υ = the scan rate. g With electrode density (1.74g / cm 3 ) to calculate the volume capacitance (C v ). The CVs at different scan rates were compared by plotting their rate-normalized current: the current divided by the corresponding scan rate.

[0263] Instrument and sample preparation

[0264] The Bragg-Brentano geometry is θ = 2θ. Powder X-ray diffraction (PXRD) patterns were recorded on a Bruker D8 advanced diffractometer with a mirror, a rotating sample stage, a LynxEye detector and a Cu Kα (λD 1.5405) X-ray source. An anti-scatter slit (2 mm) and a replaceable detector slit (8 mm) were used. The tube voltage and current were 40 kV and 40 mA, respectively. A rib accessory was used to remove low-angle scattering. Samples for PXRD were prepared by placing the electrode or powder on a zero-background silicon (510) crystal plate. The polarized Ni3BHT1 electrode was prepared by pressing Ni3BHT1 powder on Ni foam and polarizing in a three-electrode cell. First, the fabricated cell was allowed to stand overnight and then cycled for 100 cycles at a scan rate of 10 mV / sec and kept at -1.7 V vs. OCP for 5 minutes before disassembly.

[0265] Selected area electron diffraction (SAED) images were obtained with a JEOL-2100 operated at an accelerating voltage of 200 kV. The sample was drop-cast onto a Cu TEM grid from a powder dispersed in methanol. Scanning electron microscope (SEM) images were recorded using a Zeiss Supra 55VP FEG SEM using an InLens detector at an operating voltage of 3 kV. Nitrogen adsorption isotherms were measured using a Micromeritics ASAP 2020 surface area and porosity analyzer using a liquid nitrogen bath (77 K). Prior to analysis, the sample was heated to 90 ° C for 24 hours under a vacuum of 0.2 mTorr. Thermogravimetric analysis (TGA) was performed on a TA instrument Q500 thermogravimetric analyzer at a heating rate of 1 ° C / minute under a nitrogen flow of 10 mL / minute on a platinum pan.

[0266] The results were obtained on a Bruker NEO 500 (Bo = 11.75 T, 500 MHz) equipped with a 4 mm double-resonance HX magic angle spinning (MAS) Bruker NMR probe. 1 H) Solid-state NMR spectrometer 7 Li NMR experiments. Powder samples were loaded into a 4mmo.d. ZrO2 NMR rotor and closed with a Kel-F cap. NMR data were collected using either Bloch decay or Hahn echo (γB1 / 2π=62.5kHz) pulse sequences and acquired with MAS at a spinning frequency of 14kHz. Bloch pulse experiments implemented π / 4 (2μs) or π / 2 (4μs) excitation pulses, and Hahn echo pulses were optimized for each sample. Cycle delay was measured by inversion recovery method. 7 The Li nuclear rotation lattice relaxation (T1) time was determined and varied between 75 ms and 300 ms. 7LiNMR spectra were all referenced to 0 ppm using 1 M LiCl solution as an external reference. NMR spectra were processed in Topspin using exponential line broadening at -5 Hz. Data were also attempted using 1 H decoupling, however, since the NMR linewidth is not significantly affected by the internal 1 H- 7 The influence of Li heteronuclear dipole coupling is not presented. The samples are prepared as soaked in electrolyte only or as negatively polarized in supercapacitors. The soaked samples are prepared by adding ~2ml of LiPF6 / MeCN electrolyte to 25mg of Ni3BHT in a glass bottle and allowing the soaked samples to stand overnight. The polarized Ni3BHT1 electrode is prepared by pressing the Ni3BHT1 powder into pellets and polarizing in a three-electrode cell. First, the fabricated battery is allowed to stand overnight, and then the fabricated battery is scanned 20 cycles at 5mV / second in a potential range of 0V to -1.7Vvs.OCP, and is kept at -1.7V for 5 minutes before disassembly. Both the soaking process and the polarization process lead to the adsorption of Li ions at various available adsorption sites, and therefore allow the local chemical environment to be analyzed using ssNMR technology. The wet sample of the soaked powder and the polarized electrode of Ni3BHT1 are gently washed with MeCN solvent to remove excess electrolytic ions present in the macropores as free substances, and then dried under vacuum.

[0267] X-ray absorption spectroscopy (XAS) experiments were performed at the 10-BM beamline at the Advanced Photon Source (APS) at Argonne National Laboratory. All measurements were performed in transmission mode at the Ni K edge (8.333 keV) in a fast scan from 250 eV below the edge to 550 eV above the edge, which took about 10 minutes per scan. The sample was pressed into a stainless steel sample holder and placed in a sample cell. The cell was sealed and transferred to the beamline for measurement. At the Ni K edge, a simulated Ni-S (CN = 1, ) scattering pair. Calibrate S by assembling foil o 2 This was found to be 0.75. For each range in the spectrum to The k3-weighted Fourier transformed data in the R-space and isolated q-space were subjected to least squares fitting of the first shell to fit the amplitude and imaginary components. The polarized Ni3BHT1 sample was prepared by using the original Ni3BHT1 pellet as the working electrode in the three-electrode cell. First, the electrode was allowed to stand overnight, and then it was scanned at 5mV / sec for 20 cycles in the potential range of 0V to -1.7V vs.OCP and held at -1.7V for 5 minutes before disassembly. Upon disassembly, the working electrode was carefully collected, rinsed with MeCN and dried.

[0268] X-ray photoelectron spectroscopy (XPS) was performed using a photoelectron spectrometer K-α XPS system (Thermo Scientific) equipped with a hemispherical analyzer. The spectra were acquired with an analyzer energy resolution of 0.1 eV using a monochromatic aluminum source Al Kα (ED 1,486.6 eV) with a beam spot size of 400 microns in a standard emission geometry. Surface charge neutralization was performed using a low energy reading electron gun. The spectra were referenced to the charges of the indefinite C1s, CC peaks at 284.8 eV. Polarized samples for non-in-situ analysis were prepared similarly to XAS samples.

[0269] Table 1. Performance indicators of Ni3BHT1.

[0270]

[0271] Table 2. Characteristics of pristine and negatively polarized Ni3BHT1 obtained by X-ray absorption spectroscopy

[0272]

[0273] X-ray diffraction pattern under polarization

[0274] The PXRD patterns of the original Ni3BHT1 and the negatively polarized electrode showed similar patterns without obvious peak position changes ( Fig.37 ), indicating that in Li + The data suggest that the electrolysis of Li + Ions may undergo partial or complete desolvation during intercalation.

[0275] Ni3HITP2 as a control material for NMR

[0276] The samples immersed in 1M LiPF6 electrolyte or negatively polarized were 7Li NMR studies. Both the soaking process and the polarization process result in the adsorption of Li ions at various available adsorption sites and therefore allow the local chemical environment to be analyzed using NMR techniques. The wet samples were gently washed with acetonitrile to remove excess electrolytic ions that remained as free species and then dried under vacuum. NMR studies of Ni3BHT1 indicate the presence of two different chemical environments for the adsorption of Li ions and indicate the possibility of intercalated ion adsorption between 2D sheets. To further understand this additional signal from Ni3BHT1, Ni3HITP2 was studied as a control material. Both Ni3HITP2 and Ni3BHT1 have 2D structures with Ni as metal nodes and also have conductivity values ​​within two orders of magnitude.

[0277] This application also involves the following aspects:

[0278] 1. A supercapacitor electrode, comprising:

[0279] A metal-organic framework comprising a plurality of metal ions coordinated to a plurality of ligands, wherein:

[0280] The plurality of ligands include ligands including two or more sulfur donor atoms; and the metal ions are coordinated to the ligands including the sulfur donor atoms through the sulfur donor atoms.

[0281] 2. A supercapacitor electrode, comprising:

[0282] A metal-organic framework comprising a plurality of metal ions coordinated to a plurality of ligands, wherein:

[0283] The metal-organic framework is configured to interact with a second plurality of ions such that the second plurality of ions are intercalated and / or adsorbed into the metal-organic framework, and

[0284] The metal-organic framework is configured such that at least a portion of the metal ions undergo a redox reaction during charging and / or discharging of the supercapacitor electrode.

[0285] 3. A method comprising:

[0286] performing a redox reaction in a metal-organic framework comprising a plurality of metal ions coordinated to a plurality of ligands; and

[0287] A second plurality of ions is intercalated into the metal-organic framework, wherein the second plurality of ions and the metal-organic framework together have a neutral charge.

[0288] 4. A metal-organic framework comprising:

[0289] Multiple metal ions coordinated to multiple ligands, wherein:

[0290] The metal ions include nickel ions, cobalt ions, iron ions, platinum ions and / or palladium ions;

[0291] The plurality of ligands include ligands including two or more sulfur donor atoms; and the metal ions are coordinated to the ligands including the sulfur donor atoms through the sulfur donor atoms.

[0292] 5. A supercapacitor, comprising:

[0293] a first electrode comprising a first metal-organic framework; and

[0294] A second electrode comprising a second metal-organic framework, wherein:

[0295] Each metal-organic framework includes a plurality of metal ions coordinated to a plurality of ligands; and

[0296] The second metal-organic framework is different from the first metal-organic framework.

[0297] 6. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the plurality of metal ions comprises nickel ions and the plurality of ligands comprises hexamercaptobenzene ligands.

[0298] 7. A supercapacitor, a supercapacitor electrode, a metal-organic framework or a method according to any preceding aspect, wherein the metal-organic framework has the following structure: And wherein M is a nickel ion.

[0299] 8. A supercapacitor, a supercapacitor electrode, a metal-organic framework or a method according to any preceding aspect, wherein the metal-organic framework has a two-dimensional structure.

[0300] 9. A supercapacitor, a supercapacitor electrode, a metal-organic framework or a method according to any preceding aspect, wherein the metal-organic framework comprises a plurality of two-dimensional sheets.

[0301] 10. A supercapacitor, a supercapacitor electrode, a metal-organic framework or a method according to any preceding aspect, wherein the interaction energy between the plurality of two-dimensional sheets is less than the bond strength within the plurality of two-dimensional sheets.

[0302] 11. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the two-dimensional sheets are aligned with each other.

[0303] 12. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the average spacing between the two-dimensional sheets is greater than or equal to 0.3 nm and less than or equal to 1 nm.

[0304] 13. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the metal-organic framework comprises a plurality of pores.

[0305] 14. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the plurality of pores are located in the plurality of two-dimensional sheets.

[0306] 15. A supercapacitor, a supercapacitor electrode, a metal-organic framework or a method according to any preceding aspect, wherein the metal ions comprise copper ions, nickel ions, cobalt ions, iron ions, palladium ions and / or platinum ions.

[0307] 16. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein a portion of the metal ions are associated with two or more ligands.

[0308] 17. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein a portion of the ligand comprising the two or more sulfur donor atoms is associated with two or more metal ions.

[0309] 18. The supercapacitor, supercapacitor electrode, metal-organic framework or method according to any preceding aspect, wherein the ligand comprising the two or more sulfur donor atoms is a multidentate ligand.

[0310] 19. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the sulfur donor atoms are arranged around an organic core.

[0311] 20. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the organic core comprises aromatic and / or heteroaromatic rings.

[0312] 21. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the organic core comprises a plurality of fused aryl and / or heteroaryl rings.

[0313] 22. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the two or more sulfur donor atoms comprise vicinal thiol groups.

[0314] 23. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the plurality of ligands comprises hexamercaptobenzene and / or hexamercaptotriphenylene.

[0315] 24. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the second plurality of ions comprises alkali metal ions, alkaline earth metal ions, quaternary ammonium ions, quaternary ions and / or ions from ionic liquids.

[0316] 25. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the second plurality of ions comprises lithium ions, sodium ions, potassium ions, magnesium ions, calcium ions, aluminum ions, ammonium ions, tetramethylammonium ions, tetraethylammonium ions, tetrabutylammonium ions, tetrapentylammonium ions, tetrahexylammonium ions, tetraheptylammonium ions, tetraoctylammonium ions, Ion, Tetramethyl Ion, tetraethyl Ion, Tetrabutyl Ion, Tetrapentyl Ion, Tetrahexyl Ion, Tetraheptyl ion and / or tetraoctyl ion.

[0317] 26. A supercapacitor, a supercapacitor electrode, a metal-organic framework or a method according to any preceding aspect, wherein the first metal-organic framework comprises a ligand comprising two or more sulfur donor atoms, and wherein the metal ion is coordinated to the ligand comprising the sulfur donor atom through the sulfur donor atom.

[0318] 27. A supercapacitor, a supercapacitor electrode, a metal-organic framework or a method according to any preceding aspect, wherein the second metal-organic framework comprises a plurality of ligands comprising two or more amine groups, and wherein the metal ions are coordinated to the ligands comprising the amine groups through the amine groups.

[0319] 28. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the supercapacitor further comprises an electrolyte.

[0320] 29. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the electrolyte is an aqueous electrolyte.

[0321] 30. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the electrolyte is a non-aqueous electrolyte.

[0322] 31. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the electrolyte comprises a solvent.

[0323] 32. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the solvent is an organic solvent.

[0324] 33. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the electrolyte comprises an ionic liquid.

[0325] 34. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, further comprising inserting and / or adsorbing a second plurality of ions into the metal-organic framework.

[0326] 35. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the second plurality of ions are adsorbed into pores in the metal-organic framework.

[0327] 36. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the second plurality of ions are intercalated between the two-dimensional sheets of the metal-organic framework.

[0328] 37. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, further comprising deintercalating and / or desorbing the second plurality of ions from the metal-organic framework.

[0329] 38. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the second plurality of ions are desorbed from the pores in the metal-organic framework.

[0330] 39. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the second plurality of ions are intercalated from the two-dimensional sheet of the metal-organic framework.

[0331] 40. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the redox potential of the plurality of metal ions is greater than or equal to -3.0 V and less than or equal to 2 V compared to a standard hydrogen electrode.

[0332] 41. The supercapacitor, supercapacitor electrode, metal-organic framework or method of any preceding aspect, wherein the potential drop across the supercapacitor is less than or equal to 4V.

[0333] Although several embodiments of the present invention have been described and shown herein, a person of ordinary skill in the art will readily conceive of various other methods and / or structures for performing functions and / or obtaining results and / or one or more advantages described herein, and each of such changes and / or modifications is considered to be within the scope of the present invention. More generally, it will be readily understood by those skilled in the art that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on the specific one or more applications for which the teachings of the present invention are used. Those skilled in the art will recognize, or be able to determine using no more than routine experiments, many equivalents of the specific embodiments of the present invention described herein. Therefore, it should be understood that the foregoing embodiments are presented only by way of example, and within the scope of the appended claims and their equivalents, the present invention may be implemented in a manner other than specifically described and claimed. The present invention relates to each individual feature, system, article, material, and / or method described herein. In addition, if such features, systems, articles, materials, and / or methods are not mutually inconsistent, any combination of two or more such features, systems, articles, materials, and / or methods is included within the scope of the present invention.

[0334] In this specification and claims, unless explicitly indicated to the contrary, the indefinite articles "a" and "an" as used herein should be understood to mean "at least one".

[0335] The phrase "and / or" as used in this specification and claims should be understood to mean "either or both" of the elements so combined, i.e., elements that are present in combination in some cases and separately in other cases. Unless expressly indicated to the contrary, other elements may optionally be present in addition to the elements specifically identified by the "and / or" clause, whether related or not to those specifically identified elements. Thus, as a non-limiting example, when used in conjunction with open language such as "comprising," a reference to "A and / or B" may refer to: A without B (optionally including elements in addition to B) in one embodiment; B without A (optionally including elements in addition to A) in another embodiment; both A and B (optionally including other elements) in yet another embodiment; etc.

[0336] As used in this specification and claims, "or" should be understood to have the same meaning as "and / or" as defined above. For example, when the items in the list are separated, "or" or "and / or" should be interpreted as being inclusive, i.e. including at least one of a plurality of elements or element lists, and also including more than one, and optionally, other unlisted items. Only explicitly indicating the opposite terms, such as "only one" or "just one" or when used in the claims, "consisting of..." will refer to including just one element in a plurality of elements or element lists. Usually, the term "or" as used in this article only exists before an exclusive term, such as "any one", "one", "only one" or "just one" should be interpreted as indicating an exclusive alternative (that is, "one or another, not two"). When used in the claims, "substantially consisting of..." should have its ordinary meaning used in the field of patent law.

[0337] As used in this specification and claims, the phrase "at least one" when referring to a list of one or more elements should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but does not necessarily include at least one of each element specifically listed in the list of elements, and does not exclude any combination of elements in the list of elements. This definition also allows that elements other than the elements specifically identified in the list of elements to which the phrase "at least one" refers may optionally be present, whether related or irrelevant to those specifically identified elements. Thus, as a non-limiting example, "at least one of A and B" (or equivalently, "at least one of A or B", or equivalently "at least one of A and / or B") may refer to: in one embodiment, at least one, optionally including more than one A, no B (and optionally including elements other than B); in another embodiment, at least one, optionally including more than one B, no A (and optionally including elements other than A); in yet another embodiment, at least one, optionally including more than one A, and at least one, optionally including more than one B (and optionally including other elements); etc.

[0338] In the claims and in the foregoing specification, all transitional phrases such as "comprising," "including," "with," "having," "containing," "involving," "having," and the like shall be construed as open ended, i.e., meaning including, but not limited to. Only the transitional phrases "consisting of" and "consisting essentially of" shall be closed or semi-closed transitional phrases, respectively, as set forth in the U.S. Patent Office Manual of Patent Examining Procedures, Section 2111.03.

Claims

1. A supercapacitor electrode, comprising: A metal-organic framework comprising a plurality of metal ions coordinated to a plurality of ligands, wherein: The metal-organic framework is configured to interact with a second plurality of ions such that the second plurality of ions are intercalated and / or adsorbed into the metal-organic framework, and The metal-organic framework is configured such that at least a portion of the metal ions undergo a redox reaction during charging and / or discharging of the supercapacitor electrode.

2. A method comprising: performing a redox reaction in a metal-organic framework comprising a plurality of metal ions coordinated to a plurality of ligands; as well as A second plurality of ions is intercalated and / or adsorbed into the metal-organic framework, wherein the second plurality of ions and the metal-organic framework together have a neutral charge.

3. The supercapacitor electrode or method of any preceding claim, wherein the second plurality of ions comprises alkali metal ions, alkaline earth metal ions, quaternary ammonium ions, quaternary ions and / or ions from ionic liquids.

4. The supercapacitor electrode or method of any preceding claim, wherein the second plurality of ions comprises lithium ions, sodium ions, potassium ions, magnesium ions, calcium ions, aluminum ions, ammonium ions, tetramethylammonium ions, tetraethylammonium ions, tetrabutylammonium ions, tetrapentylammonium ions, tetrahexylammonium ions, tetraheptylammonium ions, tetraoctylammonium ions, Ion, Tetramethyl Ion, tetraethyl Ion, Tetrabutyl Ion, Tetrapentyl Ion, Tetrahexyl Ion, Tetraheptyl ion and / or tetraoctyl ion.

5. A method according to any preceding claim, wherein the second plurality of ions are intercalated between two-dimensional sheets of the metal-organic framework.

6. A method according to any preceding claim, wherein the second plurality of ions are adsorbed into pores of the metal-organic framework.

7. The method according to any preceding claim, further comprising deintercalating and / or desorbing the second plurality of ions from the metal-organic framework.

8. The method of claim 7, wherein the second plurality of ions are deintercalated from the two-dimensional sheet of the metal-organic framework.

9. The method of any one of claims 7 to 8, wherein the second plurality of ions are desorbed from the pores of the metal-organic framework.

10. A supercapacitor, comprising: a first electrode comprising a first metal-organic framework; as well as A second electrode comprising a second metal-organic framework, wherein: Each metal-organic framework includes a plurality of metal ions coordinated to a plurality of ligands; and The second metal-organic framework is different from the first metal-organic framework.

Images