Synthesis of metal selenide-carbon material based on MOF

Abstract

The present invention relates to the synthesis of pure metal or multi-metal derivatives of ZIF-11, ZIF-12 or amorphous ZIF structures in high yield followed by calcination under inert conditions to produce in composite nanostructures one or more metal selenide dispersed on the surface of or embedded in a carbon matrix, and using these composites as electrodes for lithium ion batteries, sodium ion batteries, potassium ion batteries, supercapacitors or fuel cells.

Description

Technical Field

[0001] This invention relates to the efficient synthesis of ZIF-11, ZIF-12 or amorphous ZIF structures (pure metal or multimetal derivatives), followed by calcination under inert conditions to produce composite nanostructured metal selenide materials dispersed or embedded on large-area carbon surfaces, and to the use of these composite materials as electrodes for lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors or fuel cells. Background Technology

[0002] Currently, transition metal selenides (TMSe) are favored due to their large specific surface area and excellent electronic conductivity (1×10⁻⁶). -3 S m -1 With its high electrochemical activity, selenide-based electrodes are considered preferred electrode materials for many energy storage systems. They exhibit high cycle stability during charge-discharge processes by forming polyselenide intermediates. In recent years, many single, binary, or multi-component composite metal selenide materials have been prepared. These materials are particularly important for use as electrodes in lithium-ion batteries, sodium-ion batteries, supercapacitors, and fuel cells.

[0003] In energy storage devices, metal selenides, with their high energy density and high conductivity, have the potential to replace traditional electrode materials. However, their structural instability necessitates further development. When metal selenides are used as electrodes, this structural instability leads to low activity and short cycle life. Furthermore, the volume expansion of the metal within the various metal selenide structures used in electrode materials during charge and discharge processes, and the resulting structural degradation, are considered major problems for these electrode materials.

[0004] The prior art document CN106654221A relates to a three-dimensional porous carbon-coated zinc selenide material for lithium-ion battery anodes and its preparation method. This document belongs to the field of materials and energy technology and relates to a three-dimensional porous carbon-coated zinc selenide material for lithium-ion battery anodes and its preparation method. This document mentions the use of metal selenides and carbon structures. However, the present invention does not mention the synthesis of single, dual, or three different metal selenides embedded or dispersed on the surface of a composite porous carbon structure obtained by pyrolysis of a metal-organic framework structure (ZIF-11, ZIF-12, or amorphous ZIF), nor its use as an electrode in lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors, or fuel cells. The ZIF-8 structure in document CN106654221A is a material with extremely low synthesis yield. Furthermore, only the zinc selenide structure was obtained and it was only used in lithium-ion batteries. Therefore, the ZIF-8 structure has no similarity to the material of the present invention in terms of synthesis, composition, and application.

[0005] Document CN115893329A relates to a method for preparing a selenium-doped cobalt ditelluride electrode material. This document mentions a method for preparing a selenium-doped cobalt ditelluride electrode material suitable for the field of sodium-ion battery technology. However, the ZIF-67 structure used in document CN115893329A is a high-cost material due to its low synthesis efficiency. Furthermore, although the ZIF structures of this invention (ZIF-11, ZIF-12, or amorphous ZIF) differ, these materials contain one or more different metal selenide structures. Therefore, it has no similarity to the work of related patents.

[0006] Therefore, current improvements to electrode materials used in lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors, or fuel cells still have some drawbacks; thus, new structures are needed to reduce or eliminate these drawbacks and provide solutions for existing systems. Summary of the Invention

[0007] The present invention relates to composite porous nitrogen-containing carbon materials comprising one, two or three different metal selenide structures, which meet the above requirements, minimize or eliminate all disadvantages, and bring some additional advantages.

[0008] The main objective of this invention is to synthesize electrode materials that can be used as electrodes for lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors, or fuel cells by using composite porous nitrogen-containing carbon materials containing one, two, or three different metal selenide structures.

[0009] One object of the present invention is to provide high capacity, high charge-discharge cycle performance and low capacitance degradation in energy storage and conversion systems (as anodes and cathodes of lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors, fuel cells, etc.), while also having designable carbon properties and the possibility of synthesizing two or three different metal selenide structures using these materials.

[0010] Another objective of this invention is to promote electron and ion conduction during charge and discharge by using conductive, flexible, porous, and nitrogen-containing carbon networks prepared using zeolite imidazole ester framework (ZIF) or single / multi-metal-organic framework (MOF) structures as templates, and to minimize the volume expansion of metals by utilizing the flexible structure of the carbon network material, thereby ensuring that the electrochemical performance of these materials remains at a high level, forming a stable solid electrolyte interface (SEI) layer in the battery, and achieving a long cycle life.

[0011] To fully understand the structural features, characteristics, and all advantages of the present invention, an evaluation should be conducted in conjunction with the following detailed description. Detailed Implementation

[0012] In this detailed description, preferred embodiments of the synthesis of composite porous nitrogen-containing carbon materials comprising one, two, or three different metal selenide structures are described in a non-limiting manner to better understand the subject matter of the invention.

[0013] By doping metal selenides with porous nitrogen-containing carbon materials, the drawbacks of metal selenides, such as volume expansion and unstable SEI layer formation, can be minimized. Furthermore, using ZIFs and MOFs, which are the sources of the conductive, flexible, nitrogen-containing porous carbon structures obtained in this invention, two or more different types of metal selenides can be synthesized. Due to the synergistic effect between the metals, the electrochemical performance of these metal selenides can be improved, or experimental performance close to their theoretical values ​​can be obtained. In this regard, the use of MOFs or ZIFs in the preparation of transition metal selenide-carbon (TMSe-carbon) composites can provide high performance in energy storage and conversion systems (as anodes and cathodes of lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors, fuel cells, etc.) due to their designable carbon properties and the possibility of using two or more metals. Conductive carbon networks prepared using ZIF or MOF structures as templates promote electron and ion conduction, and the flexible structure of the carbon network material minimizes the volume expansion of the metals, enabling these materials to maintain high electrochemical performance, form stable SEI layers, and achieve low capacitance drop and high cycle life.

[0014] This invention relates to the synthesis of single, dual, or triple metal selenide-carbon materials from ZIF or MOF-based (single or multi-metal) materials, and methods thereof. Within the scope of this invention, ZIF-11, ZIF-12, and amorphous ZIF structures are particularly discussed.

[0015] The ZIF-11 structure preferably comprises 66.6% ligand and 33.3% Zn(OAc)₂·2H₂O. NH₄OH, methanol, and toluene are also used in the synthesis. Selenium is also used in the synthesis process. Selenium can be used in different proportions during TMSe formation. Copper, cobalt, iron, manganese, tin, and nickel salts are added to this structure to obtain multi-metallic materials. The proportions of these salts are adjusted according to the amount of zinc in the ZIF structure. The ZIF-12 structure preferably comprises 66.6% benzimidazole and 33.3% Co(OAc)₂·4H₂O. NH₄OH, methanol, and toluene are also used in the synthesis. Selenium is also used in the synthesis process. Selenium can be used in different proportions during TMSe formation. One or two of copper, zinc, iron, manganese, tin, and nickel salts are added to this structure to obtain multi-metallic materials. The proportions of these salts are adjusted according to the amount of cobalt in the ZIF structure.

[0016] The amorphous ZIF structure preferably comprises 66.6% benzimidazole and its derivatives and 33.3% cobalt, zinc, and nickel salts. Additionally, NH4OH, methanol, and toluene are used in the synthesis. Selenium is also used in the synthesis process. Selenium can be used in different proportions in the formation of TMSe. One or two of copper, cobalt, zinc, iron, manganese, tin, and nickel salts are added to the structure to obtain multi-metallic materials. The proportions of these salts are adjusted according to the amount of base ZIF metals in the ZIF structure.

[0017] Benzimidazole and its derivatives are among the main components of the ZIF structure. Co(OAc)₂·4H₂O, Zn(OAc)₂·2H₂O, and Ni(OAc)₂·4H₂O salts are metal sources used for the synthesis of ZIF-11, ZIF-12, and amorphous ZIFs. These salts are low in toxicity and inexpensive. Copper, iron, tin, manganese, and nickel salts used in the synthesis of bimetallic ZIFs are inexpensive compounds. NH₄OH is an readily available base used to enhance the reactivity of the ligands. Methanol and toluene are solvents used in the ZIF synthesis reactions. They can be purified by distillation and reused. Metallic selenium is an element used in the synthesis of TMSe.

[0018] The synthesis of metal selenide-carbon nanoparticle materials is mainly achieved through three steps.

[0019] Synthesize ZIF structures (ZIF-11, ZIF-12 or amorphous ZIF).

[0020] Different types of metals are added (doped) into ZIF-11, ZIF-12 or amorphous ZIF structures to synthesize multi-metallic ZIFs.

[0021] Selenium treatment and carbonization (calcination).

[0022] The synthesis method includes the following steps in more detail.

[0023] Dissolve 2 mmol of benzimidazole or its derivative in a methanol / toluene (150 mmol / 50 mmol) mixture in a flask.

[0024] Add 4 mmol of NH4OH to the mixture.

[0025] To the resulting solution: For ZIF-11: add Zn(OAc)2·2H2O and tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol to 1 mmol.

[0026] For ZIF-12: add Co(OAc)2·4H2O and tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol to 1 mmol.

[0027] For amorphous ZIF: add Co(OAc)2·4H2O or Zn(OAc)2·2H2O or Ni(OAc)2·4H2O and tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol to 1 mmol, and stir at room temperature for 3 hours.

[0028] The solid was filtered, washed with methanol, and dried in an oven at 70°C.

[0029] The resulting solid was mixed with metallic selenium and carbonized at 400-900°C for 3-5 hours.

[0030] As a result of the carbonization process, nanomaterials were obtained, which were used as anodes or cathodes in lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors, heterogeneous catalysts, and fuel cells.

[0031] During the synthesis process, the ZIF synthesis time can be in the range of 2-3 hours. The metal doping time can be in the range of 1-2 hours. The ZIF drying temperature can be applied in the range of 50-80°C. The ZIF drying temperature should not exceed 80°C. The Se / ZIF mixing ratio for calcination can be between 1 and 3. The Se / ZIF mixing ratio for carbonization should not exceed 3. The carbonization temperature can be applied between 400-900°C. The synthesis time of multi-metal ZIF should not exceed 2 hours.

Claims

1. A carbon material, characterized in that, It is a composite porous nitrogen-containing carbon material obtained from single or multi-metal ZIF or MOF structures, and is used as an electrode in lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors or fuel cells.

2. The carbon material according to claim 1, characterized in that, The single or multi-metal structure is ZIF-11, ZIF-12, or an amorphous ZIF structure.

3. The carbon material according to claim 1 or 2, characterized in that, For the ZIF-11 structure, the single or multi-metal structure comprises at least two of copper, cobalt, manganese, tin and nickel salts.

4. The carbon material according to claim 1 or 2, characterized in that, For the ZIF-12 structure, the zeolite imidazole ester structure comprises at least two of the following: copper, zinc, iron, manganese, tin, and nickel salts.

5. The carbon material according to claim 1 or 2, characterized in that, For the amorphous ZIF structure, the zeolite imidazole ester structure comprises at least two of copper, cobalt, zinc, iron, manganese, tin and nickel salts.

6. A method for synthesizing carbon materials from single or multi-metal ZIF or MOF structures, wherein the carbon materials are used as electrodes in lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, supercapacitors, or fuel cells, the method comprising the following process steps: Synthesize ZIF structures (ZIF-11, ZIF-12 or amorphous ZIF). Different types of metals are added (doped) into ZIF-11, ZIF-12 or amorphous ZIF structures to synthesize multi-metal ZIFs; Selenium treatment and carbonization (calcination).

7. The method for synthesizing carbon materials according to claim 6, characterized in that, include: Dissolve 2 mmol of benzimidazole or its derivative in a methanol / toluene (150 mmol / 50 mmol) mixture in a flask; Add 4 mmol of NH4OH to the mixture; Add to the resulting solution: For ZIF-11: add Zn(OAc)2·2H2O and tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol to 1 mmol; For ZIF-12: add Co(OAc)2·4H2O and tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol to 1 mmol; For amorphous ZIF: add Co(OAc)2·4H2O or Zn(OAc)2·2H2O or Ni(OAc)2·4H2O and tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol-1 mmol, and stir at room temperature for 3 hours; The solid was filtered, washed with methanol, and dried in an oven at 70°C. The solid was mixed with metallic selenium and carbonized at 400-900°C for 3-5 hours.