Carbon aerogel derived from MOFs, its manufacturing method, and application to lithium-ion batteries

Abstract

The present invention relates to the technical field of lithium-ion batteries, and provides a MOFs-derived carbon aerogel, a manufacturing method thereof, and an application to lithium-ion batteries. The present invention first manufactures [Cd(tppa)2Cl2], which is a kind of macroporous metal-organic framework material (MOFs). When carbonization is carried out using this, the obtained MOFs-derived carbon aerogel has the characteristics of being porous and lightweight, and can have more lithium storage space in the process of lithium ions desorbing lithium. The performance of the material remains stable even after many cycles. The MOFs-derived carbon aerogel of the present invention is used as a negative electrode active material of a lithium-ion battery, has extremely excellent electrochemical performance, not only has ultra-long cycle ability and extremely high rate performance, but also has a high reversible capacity at a small current density, and is promising as a negative electrode material for the commercialization of next-generation lithium-ion batteries to replace graphite.

Description

[Technical Field]

[0001] The present invention relates to the technical field of lithium ion batteries, and in particular to MOF-derived carbon aerogels and their preparation methods and applications in lithium ion batteries. [Background technology]

[0002] The energy crisis is a major issue facing human society in the 21st century, and once fossil energy is consumed, it cannot be replenished in nature in a short period of time. Lithium-ion batteries have many advantages, such as long cycle life, high operating voltage, high specific energy, excellent safety, high energy density, low self-discharge, fast charge / discharge, and wide operating temperature range, making them one of the most popular energy storage methods.

[0003] The main components of a lithium-ion battery are the positive electrode, negative electrode, electrolyte, and separator, and the electrochemical performance of the negative electrode is a key factor affecting the performance of the lithium-ion battery. Currently, the most commonly used negative electrode material for lithium-ion batteries is graphite. However, commercial graphite negative electrode materials have drawbacks such as low theoretical capacity, poor layered structural stability, and poor rate performance, which restrict the further development of lithium-ion batteries. Therefore, there is an urgent need to develop a negative electrode material with high stability and excellent electrochemical performance. Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, the present invention provides a MOF-derived carbon aerogel, a method for producing the same, and its application in lithium-ion batteries. The MOF-derived carbon aerogel provided by the present invention has excellent charge / discharge performance, a high specific capacity, extremely high rate performance, and extremely strong cycle stability. [Means for solving the problem]

[0005] In order to achieve the above object of the invention, the present invention provides the following technical scheme.

[0006] The method for producing carbon aerogels derived from MOFs includes the following steps:

[0007] A dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine and a methanol solution of CdCl2 were mixed to carry out a coordination reaction, yielding [Cd(tppa)2Cl2].

[0008] The [Cd(tppa)2Cl2] is carbonized under a protective atmosphere to obtain MOF-derived carbon aerogel.

[0009] Preferably, the molar ratio of the 4,4',4"-tris(4-pyridyl)triphenylamine to CdCl2 is 6-8:2-3, and the temperature of the coordination reaction is room temperature.

[0010] Preferably, the method for mixing the dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine and the methanol solution of CdCl includes Method 1 or Method 2. Method 1 includes a step of adding the dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine dropwise to the methanol solution of CdCl.

[0011] Method 2 involves placing a dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine at the bottom of a reaction vessel, followed by adding a dichloromethane-methanol mixed solution, and then adding a methanol solution of CdCl2.

[0012] When mixing is performed by Method 1, the coordination reaction time is 20 to 30 hours, and when mixing is performed by Method 2, the coordination reaction time is 24 to 27 days.

[0013] Preferably, the [Cd(tppa)2Cl2] is a powder crystal or a single crystal. The crystal data of the single crystal indicates that it belongs to the monoclinic system P21 / c, and the asymmetric unit contains one Cd IIion, two ligand tppa molecules, and two chloride ions.

[0014] Preferably, the carbonization temperature is 800 to 1000° C., the heat retention time is 3 to 4 hours, and the atmosphere is nitrogen gas.

[0015] The present invention also provides a MOF-derived carbon aerogel produced by the production method described in the above scheme, wherein the density of the MOF-derived carbon aerogel is 0.2 to 0.4 mg / cm. 3 and the porosity is 85 to 95%.

[0016] The present invention also provides an application of the MOF-derived carbon aerogel described in the above scheme as an anode active material in lithium-ion batteries.

[0017] The present invention also provides a negative electrode of a lithium ion battery, wherein the negative electrode active material used in the negative electrode of the lithium ion battery is the MOFs-derived carbon aerogel according to the above scheme.

[0018] Preferably, the negative electrode of the lithium ion battery includes a current collector and an active material layer coated on the surface of the current collector. The active material layer includes a negative electrode active material, a conductive agent, and a binder.

[0019] The present invention also provides a lithium ion battery, wherein the negative electrode of the lithium ion battery is the negative electrode of the lithium ion battery described in the above scheme.

[0020] The present invention provides a method for producing MOF-derived carbon aerogel, which includes the following steps: mixing a dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine with a methanol solution of CdCl2 to carry out a coordination reaction to obtain [Cd(tppa)2Cl2], and then calcining the [Cd(tppa)2Cl2] under a protective atmosphere to obtain MOF-derived carbon aerogel. The present invention first produces [Cd(tppa)2Cl2], which is a type of macroporous metal-organic framework (MOF), and then carbonizing it. The resulting MOF-derived carbon aerogel is porous and lightweight, and has more lithium storage space during the lithium desorption process, maintaining stable performance even after many cycles. The MOF-derived carbon aerogel of the present invention can be used as an anode active material in lithium-ion batteries. Its electrochemical performance is excellent, with ultra-long cycle capability and extremely high rate performance, as well as high reversible capacity at low current densities. This makes it a promising anode material for commercializing next-generation lithium-ion batteries, replacing graphite.

[0021] As a result of the Examples, when a lithium ion battery was manufactured using the MOF-derived carbon aerogel of the present invention as a negative electrode active material, the operating voltage of the obtained lithium ion battery was between 0.01 and 3.5 V, and the discharge specific capacity after 170 cycles at a current density of 0.5 A / g was as high as 500 mAh / g, and it was found that it could be stably cycled 10,000 times at a large current density of 10 A / g. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a diagram of the CdII ion coordination configuration of MOF-ZX-4. [Figure 2] Figure 1 shows the "diamond" (4,4) network diagram of MOF-ZX-4. [Figure 3] FIG. 1 is an SEM image of a MOFs-derived carbon aerogel product produced in Example 1. [Figure 4]Figure 3 shows the CV diagram of the half cell assembled using the carbon aerogel derived from MOFs in Example 2 at a scan speed of 0.1 m / s, and the test results are shown in Figure 3 . [Figure 5] FIG. 1 is a Nyquist diagram of a half cell assembled using carbon aerogel derived from MOFs in Example 2. [Figure 6] FIG. 1 shows the rate performance of the half cell assembled using the MOF-derived carbon aerogel in Example 2 at currents of 0.1 A / g, 0.2 A / g, 0.5 A / g, 1 A / g, 2 A / g, 5 A / g, and 0.1 A / g. [Figure 7] FIG. 10 is a graph showing the cycle performance of the half-cell assembled using the MOFs-derived carbon aerogel in Example 2 at a current of 5 A / g. [Figure 8] FIG. 10 shows the cycle performance of the half-cell assembled using the MOFs-derived carbon aerogel in Example 2 at a current of 10 A / g. [Figure 9] FIG. 10 is a graph showing the cycle performance of the half cell assembled using the MOFs-derived carbon aerogel in Example 3 at a current density of 0.5 A / g. DETAILED DESCRIPTION OF THE INVENTION

[0023] The present invention provides a method for producing carbon aerogels derived from MOFs, comprising the steps of:

[0024] A dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine and a methanol solution of CdCl2 were mixed to carry out a coordination reaction, yielding [Cd(tppa)2Cl2].

[0025] The [Cd(tppa)2Cl2] is carbonized under a protective atmosphere to obtain MOF-derived carbon aerogel.

[0026] In the present invention, a dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine is mixed with a methanol solution of CdCl2 to carry out a coordination reaction, thereby obtaining [Cd(tppa)2Cl2]. In the present invention, the English name of the 4,4',4"-tris(4-pyridyl)triphenylamine is tris(4-(pyridin-4-yl)phenyl)amine, abbreviated as tppa. The molar ratio of the 4,4',4"-tris(4-pyridyl)triphenylamine to CdCl2 is preferably 6 to 8:2 to 3, more preferably 6:2. The concentration of the dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine is preferably 0.075 to 0.013 mol / L, more preferably 0.01 mol / L. The concentration of the methanol solution of CdCl2 is preferably 0.0025 to 0.005 mol / L, more preferably 0.003 to 0.004 mol / L. The method for mixing the dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine and the methanol solution of CdCl2 includes Method 1 or Method 2. Method 1 includes a step of adding the dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine dropwise to the methanol solution of CdCl2. In the present invention, it is preferred to first add a methanol solution of CdCl2 to an Erlenmeyer flask, and then add a dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine dropwise through a constant-pressure dropping funnel. Method 2 involves the following steps: placing the dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine at the bottom of a reaction vessel, then adding a dichloromethane-methanol mixed solution, and then adding the methanol solution of CdCl2. The volume ratio of dichloromethane to methanol in the dichloromethane-methanol mixed solution is preferably 1:1, and the volume ratio of the dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine to the dichloromethane-methanol mixed solution is preferably 6-8:8-10. The reaction vessel is preferably a test tube. In the present invention, Method 1 is used to synthesize powder crystals, which meets the requirements of rapid industrialization, while Method 2 can grow white, bulky single crystal structures suitable for X-ray structural analysis.

[0027] In the present invention, the temperature of the coordination reaction is preferably room temperature, and when mixing is performed by Method 1, the time for the coordination reaction is preferably 20 to 30 hours, specifically, the resulting mixture is first stirred and reacted at room temperature for 8 to 13 hours, and then left to react for 12 to 17 hours.When mixing is performed by Method 2, the time for the coordination reaction is preferably 24 to 28 days, specifically, the resulting mixture is sealed and left to react.

[0028] After the coordination reaction is completed, the mother liquor is filtered, and the resulting precipitate is washed and dried to obtain [Cd(tppa)Cl] (referred to as MOF-ZX-4). The cleaning detergent is preferably ethanol, and the drying temperature is preferably 70°C. The resulting MOF-ZX-4 is a white powder.

[0029] In the present invention, the [Cd(tppa)2Cl2] is a powder crystal or a single crystal, and the crystal data of the single crystal indicates that it belongs to the monoclinic system P21 / c, and the asymmetric unit contains one Cd II ion, two ligand tppa molecules, and two chloride ions.

[0030] After obtaining [Cd(tppa)Cl], the present invention carbonizes the [Cd(tppa)Cl] under a protective atmosphere to obtain a MOF-derived carbon aerogel. In the present invention, the carbonization temperature is preferably 800 to 1000°C, more preferably 800 to 900°C, the heating rate to the carbonization temperature is preferably 5°C / min, the heat retention time for the carbonization is preferably 3 to 4 hours, more preferably 3 to 3.5 hours, the protective atmosphere is preferably nitrogen gas, and the carbonization is preferably carried out in a tube furnace. After carbonization, natural cooling to room temperature is sufficient.

[0031] The present invention also provides a MOF-derived carbon aerogel produced by the production method described in the above scheme, and the density of the MOF-derived carbon aerogel is preferably 0.2 to 0.4 mg / cm.3 The porosity is preferably 85 to 95%.

[0032] The present invention also provides application of the MOF-derived carbon aerogel described in the above scheme as an anode active material for lithium-ion batteries. The MOF-derived carbon aerogel provided by the present invention is lightweight and porous, and can be used as an anode active material for lithium-ion batteries. It exhibits excellent electrochemical performance, excellent cycle stability, high rate performance, and high reversible capacity at low current densities, making it a promising alternative to graphite as an anode material for next-generation lithium-ion batteries.

[0033] The present invention also provides a negative electrode for a lithium-ion battery, in which the negative electrode active material used in the negative electrode is the MOF-derived carbon aerogel described in the above scheme. In the present invention, the negative electrode for the lithium-ion battery preferably includes a current collector and an active material layer coated on the surface of the current collector. The active material layer preferably includes a negative electrode active material, a conductive agent, and a binder. The conductive agent is preferably acetylene black, and the binder is preferably polyvinylidene fluoride (PVDF). The mass ratio of the negative electrode active material, the conductive agent, and the binder is preferably 7:1:2. The present invention does not require any particular type of current collector; any material known to those skilled in the art, such as copper foil, is sufficient. In the present invention, when the negative electrode is a wafer with a diameter of 12 cm, the amount of negative electrode active material carried in the negative electrode for the lithium-ion battery is preferably 1 to 2 mg per wafer.

[0034] The present invention does not require any special requirements for the method of manufacturing the negative electrode of the lithium ion battery, and any method known to those skilled in the art may be employed. For example, the negative electrode active material, the conductive agent, and the binder may be mixed together, and then an appropriate amount of N-methylpyrrolidone solvent may be added and mixed uniformly. The resulting slurry may be applied to the surface of the current collector and then dried.

[0035] The present invention also provides a lithium-ion battery, the negative electrode of which is the lithium-ion battery negative electrode described in the above scheme. In the present invention, the lithium-ion battery includes a positive electrode, a negative electrode, a separator, and an electrolyte. The present invention does not require any specific requirements for the types of the positive electrode, separator, and electrolyte; any materials known to those skilled in the art may be used. In a specific embodiment of the present invention, the positive electrode is preferably a lithium sheet, the separator is preferably Celgard 2500, and the electrolyte is preferably a LiPF solution. The solvent for the electrolyte is preferably a mixed solvent of ethylene carbonate (EC) and dimethyl carbonate (DMC), with the volume ratio of EC to DMC in the mixed solvent being preferably 3:7 or 1:1. The concentration of LiPF in the electrolyte is preferably 1 mol / L. An additive may be added to the electrolyte, preferably fluorinated ethylene carbonate (FEC), with the mass fraction of FEC in the electrolyte being preferably 5%.

[0036] The technical solutions of the present invention will be described below clearly and completely in conjunction with the embodiments of the present invention, but it is clear that the described embodiments are only a part of the embodiments of the present invention, and are not all of the embodiments. All other embodiments obtained based on the embodiments of the present invention without the need for creative work by those skilled in the art fall within the scope of protection of the present invention.

[0037] Example 1

[0038] 0.6 mmol of TPPA and 0.2 mmol of CdCl2 were dissolved in dichloromethane (60 mL) and methanol (60 mL), respectively, to obtain a clear solution. The CdCl2 methanol solution was placed in an Erlenmeyer flask, and the TPPA dichloromethane solution was slowly added dropwise to the methanol solution through a constant-pressure dropping funnel. After stirring at room temperature for 8 h and allowing to stand for 12 h, the mixture was suction filtered to collect the white precipitate, which was then washed three times with 10 mL of ethanol. The resulting white powder was dried at 70 °C to obtain MOF-ZX-4 (yield: ~60%). The white MOF-ZX-4 was placed in a tube furnace and heated to 800 °C at a rate of 5 °C / min under a nitrogen atmosphere. After 3 h of incubation, it was allowed to cool to room temperature, yielding the MOF-derived carbon aerogel product.

[0039] MOF-ZX-4 single crystals were also prepared for structural analysis. The method used was to dissolve the ligand 4,4',4"-tris(4-pyridyl)triphenylamine (TPPA, 0.06 mmol) in 6 mL of dichloromethane and place it at the bottom of a test tube. 8 mL of a dichloromethane / methanol mixture (1:1 volume ratio) was carefully added, and 6 mL of a methanol solution of CdCl2 (0.02 mmol) was added on top. The tube was sealed and allowed to stand. After 24 days, white, massive single crystals suitable for X-ray structural analysis were deposited on the wall of the test tube.

[0040] The mother liquor after the reaction was suction filtered, washed three times with ethanol (10 ml), and vacuum dried to obtain MOF-ZX-4 single crystals with a yield of about 30%.

[0041] The single crystal structure analysis of MOF-ZX-4 revealed that the space group of MOF-ZX-4 is monoclinic P21 / c, and the asymmetric unit contains one Cd II It was found to contain an ion, two ligand tppa molecules, and two chloride ions.

[0042] Figure 1 shows the Cd II In the ion coordination diagram, each Cd IIThe ion coordinates with four nitrogen atoms and two chloride ions from different tppa molecules, forming an octahedral coordination configuration. The Cd-N coordination bond length in the equatorial plane is between 2.180 and 2.196 Å, while the axial Cd-Cl coordination bond length reaches 2.557 Å. Therefore, Cd II The Jahn-Teller effect clearly exists for ions.

[0043] Figure 2 shows the "diamond" (4,4) network diagram of MOF-ZX-4. As can be seen from Figure 2, although the tppa molecule has three nitrogen atoms, only two nitrogen atoms are involved in the coordination during the assembly process. That is, each tppa ligand is connected to two Cd II The ions are bridged to obtain a two-dimensional "diamond" (4,4) network with a lattice size of 12.5 × 12.5 Å. 2 The pore size is on the order of nanometers.

[0044] The SEM image of the obtained MOF-derived carbon aerogel product is shown in Figure 3. Figure 3 shows that the MOF-derived carbon aerogel product has a sheet-like structure with a small number of layers, a thin thickness, a flat and smooth surface, and a translucent, silk-like appearance.

[0045] Example 2

[0046] In this example, a half-cell was used to test the electrochemical performance of the electrode material. The half-cell mainly consists of five parts: a positive electrode, a negative electrode, a separator, an electrolyte, and a battery case. Here, the positive electrode is a lithium sheet, the negative electrode is a hybrid material consisting of MOF-ZX-4-derived carbon aerogel, acetylene black, and a binder, the separator is Celgard 2500, the electrolyte in the electrolyte is 1 mol / L LiPF6, and the solvent is a mixed solvent of EC and DMC (volume ratio 3:7).

[0047] The negative electrode was produced as follows.

[0048] (1) The MOF-derived carbon aerogel prepared in Example 1, acetylene black, and PVDF were mixed in a mass ratio of 7:1:2, and an appropriate amount of N-methylpyrrolidone solvent was added and mixed uniformly to obtain a slurry.

[0049] (2) The slurry is evenly applied to the copper foil using an applicator, dried in a vacuum oven at 70°C for 10 hours, cut into electrode chips with a diameter of 12 cm, weighed, and then placed in a glove box filled with inert gas to assemble the battery.

[0050] A CV test was performed on the assembled half-cell using a Shanghai Chenhua CHI660E electrochemical station at a scan speed of 0.1 m / s, and the test results are shown in Figure 4. The results in Figure 4 show that, except for the presence of irreversible processes in the electrode material during the first scan (mainly due to the formation of an SEI film and the decomposition of the electrolyte), there were no significant changes during the subsequent second and third scans, indicating good cycle stability and reversibility.

[0051] An electrochemical impedance spectrum test was performed on the assembled half-cell using a Shanghai Chenhua CHI660E electrochemical station, and the test results are shown in Figure 5. In Figure 5, the AC impedance measurement image is composed of semicircles and straight lines, with the diameter of the semicircle representing the ease of charge transfer during the electrochemical reaction within the battery, and the straight lines representing the ease of material diffusion of lithium ions within the electrode material. The results in Figure 5 show that the impedance (Re + Rsf + Rst) value is slightly lower than 300, indicating a large impedance value.

[0052] The rate performance of the above half-cell was tested at currents of 0.1 A / g, 0.2 A / g, 0.5 A / g, 1 A / g, 2 A / g, 5 A / g, and 0.1 A / g using a land test system, and the results are shown in Figure 6. From the results of Figure 6, the half-cell assembled using the MOF-derived carbon aerogel of the present invention was able to achieve 200 mAhg at a large current of 5 A. -1 When the reversible specific capacity is maintained and the current density is returned to 0.1 A, the discharge specific capacity is 600 mAhg -1It can be seen that the material has a good structure and excellent rate performance even after a large current has passed through it.

[0053] The cycle stability of this half-cell at high currents was measured using a land test system. Figure 7 shows the cycle performance of the carbon aerogel derived from MOF-ZX-4 at a current of 5 A / g, and Figure 8 shows the cycle performance of the carbon aerogel derived from MOF-ZX-4 at a current of 10 A / g. From Figures 7 and 8, the capacity of the carbon aerogel derived from MOF-ZX-4 at a current density of 5 A / g was 100 mAhg for 5,000 cycles. -1 It can be seen that the discharge specific capacity after 10,000 cycles reaches 30 mAh / g even at a current density of 10 A / g.

[0054] Example 3

[0055] In this example, the structure of the lithium-ion battery is basically the same as in Example 1, except for the slightly different composition of the electrolyte. The electrolyte in this example is 1 mol / L LiPF6, and the solvent is a mixed solvent of EC and DMC (volume ratio 1:1) with 5% FEC additive added.

[0056] The electrochemical performance of the half cell was tested using a land test system, and a constant current test was performed at a current density of 0.5 A / g under conditions of 0.01 to 3.5 V. The test results are shown in Figure 9. From the results in Figure 9, it can be seen that the half cell of this example has a reversible capacity of 500 mAhg at a current density of 0.5 A / g for 170 cycles. -1 It is clear that it reaches

[0057] From the results of the above examples, it can be seen that the MOF-derived carbon aerogel produced by the present invention using MOF-ZX-4 as a precursor can be applied as an active material to the negative electrode of a lithium-ion battery, and has excellent charge-discharge performance of the lithium-ion battery, including a high discharge specific capacity, extremely high rate performance, and extremely high cycle stability.

[0058] It should be noted that the above are only preferred embodiments of the present invention, and those skilled in the art can make many improvements and retouches without departing from the principle of the present invention, and these improvements and retouches should also be regarded as within the protection scope of the present invention.

Claims

1. A method for producing a carbon aerogel derived from MOFs, comprising: A solution of 4,4',4"-tris(4-pyridyl)triphenylamine in dichloromethane and CdCl ２ The resulting mixture was mixed with a methanol solution of [Cd(tppa)] to carry out a coordination reaction. ２ Cl ２ and [Cd(tppa) ２ Cl ２ and carbonizing the mixture under a protective atmosphere to obtain a MOF-derived carbon aerogel. The manufacturing method according to claim 1,

2. The 4,4',4"-tris(4-pyridyl)triphenylamine and CdCl ２ 2. The method according to claim 1, wherein the molar ratio of the coordinating agent to the coordinating agent is 6-8:2-3, and the temperature of the coordinating reaction is room temperature.

3. The dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine and CdCl ２ The method of mixing the above-mentioned methanol solution includes method 1 or method 2, Method 1 is a method of dissolving 4,4',4"-tris(4-pyridyl)triphenylamine in dichloromethane with CdCl ２ dropwise into a methanol solution of Method 2 is to place a dichloromethane solution of 4,4',4"-tris(4-pyridyl)triphenylamine at the bottom of a reaction vessel, then add a dichloromethane-methanol mixed solution, and then add CdCl ２ adding a methanol solution of 2. The method according to claim 1, wherein the time for the coordination reaction is 20 to 30 hours when mixing in the method 1, and 24 to 27 days when mixing in the method 2.

4. [Cd(tppa) ２ Cl ２ ] is a powder crystal or a single crystal, and the crystal data of the single crystal is monoclinic P2 １ / c, and the asymmetric unit contains one Cd ＩＩ ion, two ligand tppa molecules, and two chloride ions.

5. 2. The method according to claim 1, wherein the carbonization temperature is 800 to 1000°C, the heat retention time is 3 to 4 hours, and the protective atmosphere is nitrogen gas.

6. A granular material having a density of 0.2 to 0.4 mg / cm produced by the method according to any one of claims 1 to 5. ３ and a porosity of 85 to 95% of a MOF-derived carbon aerogel. Use as an anode active material in lithium-ion batteries.

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