Synthesis of metal sulfide-carbon composites from ZIF-11 and ZIF-12 (single or multi-metallic) structures

Abstract

The invention relates to the high-efficiency synthesis of ZIF-11 or ZIF-12 or Amorphous-ZIF structures (single or multi-metal) derivatives, followed by their calcination with sulfur under inert conditions to synthesize metal sulfide in a composite nanostructure, either dispersed or embedded on a wide carbon surface, and the use of these composite nanomaterials as electrodes in Li-ion batteries, Li-S batteries, Na-ion batteries, K-ion batteries, supercapacitors, and fuel cells.

Description

[0001] Synthesis of Metal Sulfide-Carbon Composites from ZIF-11 and ZIF-12 (single or multi-metallic) Structures

[0002] Field of the Invention

[0003] The invention relates to the high-efficiency synthesis of ZIF-11 or ZIF-12 or amorphous-ZIF structures (single or multi-metallic) and subsequently the synthesis of metal sulfide in a composite nanostructure, either dispersed or embedded in a wide carbon surface, through calcination with sulfur under inert conditions, and the use of these composite nanomaterials as electrodes in Li-ion batteries, Li-S batteries, Na-ion batteries, K-ion batteries, supercapacitors, and fuel cells.

[0004] State of the Art

[0005] Metal sulfides, known as metal oxides (MSs, M = Fe, Co, Ni, Cu, Mo, Ti, W, Sn, Sb, etc.), have emerged as a new class of materials for energy conversion and storage applications due to their low cost and high electrochemical activities. The mentioned metal sulfides exhibit important properties such as high redox reversibility and high capacitance. They are applied in the design and efficient synthesis of metal sulfides with controlled morphologies, sizes, compositions, and micro / nano structures as electrode materials for lithium / sodium / magnesium-ion batteries and supercapacitors, as well as electrocatalysts for the oxygen reduction reaction and hydrogen evolution reaction. In the current technique, despite the high activities of the mentioned metal sulfides, their conductivity is limited. Additionally, due to their weak chemical and mechanical resistances, volume changes occur during charge / discharge cycles. This also causes the active material to flake off by disrupting the electrode structure. This situation causes the electrochemical reaction performance of these electrode materials to decrease and their cycle (charge-discharge) lifetimes to be low.

[0006] The document numbered CN116487575A encountered in the known state of the art relates to a lithium-sulfur battery positive electrode material based on Zn / Co-MOF- derived composite carbon material, its preparation method, and application. This document discusses the use of metal sulfide and carbon structures. However, metal sulfide was not formed in the material; only molten sulfur loading was performed. This structure, synthesized with Zn / Co-MOF trimesic acid ligand, is completely different from the ZIF structures subject to this invention in both morphological and synthesis method aspects. For these reasons, it bears no resemblance to our invention.

[0007] The document numbered CN116565231A relates to the preparation method and application of a field trap type micron-scale selenium or zinc sulfide cobalt composite plate electrode. This document discusses the use of metal sulfide and carbon structures. However, the ZIF-7 and ZIF-9 structures mentioned in the invention in this document are quite weak materials in terms of porosity and surface area. Therefore, they are at a disadvantage in terms of electrochemical activity. Additionally, only the OER activity has been studied. The different synthesis method, the use of only zinc and cobalt, and the limited application area do not show any similarity with our invention.

[0008] In conclusion, developments are being made in the materials used as electrodes in Li- ion batteries, Li-S batteries, Na-ion batteries, K-ion batteries, supercapacitors, and fuel cells. Therefore, new structures are needed to eliminate the aforementioned disadvantages and provide solutions to existing systems.

[0009] Aim of the Invention

[0010] The present invention relates to metal sulfide-carbon materials that meet the aforementioned requirements, eliminate all disadvantages, and bring additional advantages.

[0011] The main purpose of the invention is to synthesize a nanomaterial that can be used as an electrode in Li-ion batteries, Li-S batteries, Na-ion batteries, K-ion batteries, supercapacitors, or fuel cells by using metal sulfide structures.

[0012] One of the purposes of the invention is to increase conductivity by creating ion / electron transport channels due to the porous structure of the metal sulfide-carbon material, to retain Na+and / or Li+ions through defects and interlayer voids formed in the structure, to obtain a large number of active regions for ion / charge storage and to increase capacity, and to minimize capacity loss by minimizing the volume expansion of the metals wrapped in the flexible carbon structure.

[0013] The current invention, to realize all the advantages mentioned above and understood from the detailed explanation below, involves the high-efficiency synthesis of ZIF-11 , ZIF-12 or amorphous-ZIF structures (single or multi-metallic) derivatives, followed by the synthesis of metal sulfide in a composite nanostructure, dispersed or embedded in a wide carbon surface, through calcination with sulfur under inert conditions. This composite nanomaterial is used as an electrode in Li-ion batteries, Li-S batteries, Na- ion batteries, K-ion batteries, supercapacitors, and fuel cells.

[0014] The structural and characteristic features of the invention and all its advantages will be better understood through the detailed explanation provided below. Therefore, the evaluation should be conducted taking the explanations into account.

[0015] Detailed Description of the Invention

[0016] In this detailed explanation, the preferred structures of the metal sulfide carbon material synthesis subject to the invention are described solely for the purpose of better understanding the subject and without creating any restrictive effect.

[0017] It is possible to synthesize materials with different physical and chemical properties by derivatizing organic ligands, inorganic salts, and solvents as synthesis materials with MOF components. In addition, the morphology can also be altered by selecting the reaction conditions (temperature, concentration, solvent polarity, and pH). The MOF derivatives in question (single and multi-metallic structures of ZIF-11, ZIF-12, and amorphous-ZIF) are porous materials with high chemical and physical durability. The carbon-metal sulfide structures obtained from these materials will minimize the aforementioned disadvantages of pure metal sulfides in terms of both chemical and mechanical properties.

[0018] The invention relates to the synthesis of metal sulfide-carbon materials from ZIF-11 , ZIF-12, and amorphous-ZIF (single or multi-metal) materials and the synthesis method. The ZIF-11 structure preferably contains 66.6% ligand and 33.3% Zn(OAc)2.2H2O by content. Additionally, NH4OH, methanol, and toluene are used in the synthesis. Sulfur is also used in the synthesis process. Sulfur can be used in varying proportions in the formation of TMS. Copper, cobalt, iron, manganese, tin, and nickel salts are added to this structure for the production of multi-metallic materials. The ratio of these salts is adjusted according to the amount of zinc in the ZIF structure.

[0019] The ZIF-12 structure preferably contains 66.6% benzimidazole and 33.3% CO(OAC)2.4H2O by composition. Additionally, NH4OH, methanol, and toluene are used in the synthesis. Sulfur is also used in the synthesis process. Sulfur can be used in varying proportions in the formation of TMS. Copper, zinc, iron, manganese, tin, and nickel salts are added to this structure to obtain a multi-metallic material. The ratio of these salts is adjusted according to the amount of cobalt in the ZIF structure.

[0020] The amorphous ZIF structure preferably contains 66.6% benzimidazole and its derivatives and 33.3% cobalt, zinc, and nickel salts. Additionally, NH4OH, methanol, and toluene are used in the synthesis. Sulfur is also used in the synthesis process. Sulfur can be used in varying proportions in the formation of TMS. Copper, cobalt, zinc, iron, manganese, tin, and nickel salts are added to this structure to obtain a multi- metallic material. The ratio of these salts is adjusted according to the amount of base ZIF metal in the ZIF structure.

[0021] Benzimidazole and its derivatives are one of the key components of ZIF structures. CO(OAC)2.4H2O, Zn(OAc)2.2H2O, and Ni(OAc)2.4H2O salts are the metal sources used in the synthesis of ZIF-11, ZIF-12, and amorphous-ZIF. The toxicity of these salts is low, and they are inexpensive. The copper, iron, tin, and nickel salts used for the synthesis of bimetallic ZIFs are inexpensive compounds. NH4OH is a base used to increase the reactivity of the ligand and is easily obtainable. Methanol and toluene are solvents used in ZIF synthesis reactions. They can be purified through distillation and reused repeatedly. Metallic sulfur, on the other hand, is a low-cost material used in TMS synthesis.

[0022] The synthesis of metal sulfide-carbon nanoparticle material is primarily achieved through three method steps:

[0023] - Synthesis of the ZIF structure (ZIF-11, ZIF-12, or Amorphous-ZIF), - Addition (doping) of various types of metals to the ZIF-11 , ZIF-12, or Amorphous-ZIF structure for multi-metallic ZIF synthesis,

[0024] - Sulfurization and carbonization (calcination).

[0025] The synthesis method consists of the following detailed steps:

[0026] - Dissolving 2 mmol of benzimidazole or its derivative in a flask containing a methanol / toluene (150 mmol / 50 mmol) mixture,

[0027] - Adding 4 mmol of NH4OH to the mixture,

[0028] - Adding to the resulting solution; o For ZIF-11 , tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol-1 mmol with Zn(OAc)2.2H2O, o For ZIF-12, tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol-1 mmol with Co(OAc)2.4H2O, o For Amorphous-ZIF, tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol-1 mmol with Co(OAc)2.4H2O or Zn(OAc)2.2H2O or Ni(OAc)2.4H2O, and stirring at room temperature for 3 hours,

[0029] - Filtering the resulting solid, washing with methanol, and drying in an oven at 70 °C.

[0030] - The obtained solid is mixed with solid sulfur and carbonized under inert conditions (Ar, Ar / H2) at temperatures ranging from 400-900 °C for 3-5 hours.

[0031] As a result of the carbonization process, a nanomaterial is obtained, and the resulting material is used as an anode or cathode in Li-ion batteries, Li-S batteries, Na-ion batteries, K-ion batteries, supercapacitors, and fuel cells.

[0032] In the synthesis process, the ZIF synthesis duration can range from 2 to 3 hours. The metal plating duration 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 sulfur / ZIF ratio mixed for calcination can be between 1-5. The sulfur / ZIF ratio mixed for carbonization should not exceed 5. The carbonization temperature can be applied between 400-900 °C. The synthesis time of the multi-metallic ZIF should not exceed 2 hours.

Claims

CLAIMSObtained from MOF-derived materials, the nanoparticle material used as an electrode in Li-ion batteries, Li-S batteries, Na-ion batteries, K-ion batteries, supercapacitors, or fuel cells has the characteristic of containing carbon from the aforementioned single or multi-metal materials, metal sulfide, and metal-organic frameworks (MOFs).

1. The nanoparticle material suitable for Claim 1 , characterized by the mentioned single or multi-metallic structures, is ZIF-11, ZIF-12, and amorphous-ZIF structures.

2. A nanoparticle material suitable for Claim 1 or 2, characterized by containing at least two of the salts of copper, cobalt, manganese, tin, and nickel for the ZIF-11 structure of the mentioned single or multi-metallic structure.

3. A nanoparticle material suitable for claim 1 or 2, characterized by containing at least two of the salts of copper, zinc, iron, manganese, tin, and nickel for the ZIF-12 structure of the mentioned single or multi-metal structure.

4. The nanoparticle material suitable for Claim 1 or 2, characterized by containing at least two of the salts of copper, cobalt, zinc, iron, manganese, tin, and nickel for the amorphous-ZIF structure of the mentioned single or multi-metal structure.

5. The nanoparticle material synthesis method used as an electrode in Li-ion batteries, Li-S batteries, Na-ion batteries, K-ion batteries, supercapacitors, or fuel cells, characterized in its most general form by:• Synthesis of ZIF structures (ZIF-11, ZIF-12, or amorphous-ZIF),• Addition (doping) of various types of metals to ZIF-11 , ZIF-12, or amorphous-ZIF structures for multi-metallic ZIF synthesis,• Sulfurization and carbonization (calcination) process steps.

6. The nanoparticle material synthesis method according to claim 6, characterized by:• Dissolving 2 mmol of benzimidazole or its derivative in a flask containing a methanol / toluene (150 mmol / 50 mmol) mixture,Adding 4 mmol of NH4OH to the mixture,• To the resulting solution: o For ZIF-11 , adding tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol-1 mmol with Zn(OAc)2.2H2O, o For ZIF-12, adding tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol-1 mmol with Co(OAc)2.4H2O, o For Amorphous-ZIF, adding tin and / or copper and / or iron and / or manganese salts in the range of 0.1 mmol-1 mmol with Co(OAc)2.4H2O or Zn(OAc)2.2H2O or Ni(OAc)2.4H2O and mixing at room temperature for 3 hours,• Filtering the resulting solid, washing with methanol, and drying in an oven at 70 °C,• Mixing the obtained solid with solid sulfur and carbonizing at temperatures in the range of 400-900 °C under inert conditions (Ar, Ar / F ) for 3-5 hours.