CN-121991372-A - Electrochemical reconstruction resistant cobalt-based metal organic framework material and preparation method and application thereof

Abstract

The invention provides an electrochemical reconstruction resistant cobalt-based metal organic framework material, a preparation method and application thereof. The cobalt-based metal organic framework material has remarkably low overpotential, excellent reaction dynamics and more stable crystal structure in the oxygen evolution reaction of electrolytic water, and provides a new thought for the application of the high-efficiency stable metal organic framework in electrolytic water.

Inventors

• KOU ZONGKUI
• ZHANG XIANYANG
• LI XINGCHUAN

Assignees

• 武汉理工大学

Dates

Publication Date

20260508

Application Date

20260207

Claims (9)

1. 1. An electrochemical reconstruction resistant cobalt-based metal organic framework material is characterized in that the cobalt-based metal organic framework material is formed by coordination of trivalent cobalt and an organic ligand.
2. 2. An electrochemically reconstruction resistant cobalt-based metal organic framework material according to claim 1, wherein said salt precursor of trivalent cobalt is cobalt (III) acetylacetonate.
3. 3. An electrochemically reconstruction resistant cobalt-based metal organic framework material according to claim 2, wherein said organic ligand is one or more of 2-methylimidazole, 2-ethylimidazole and 2-propylimidazole.
4. 4. A method for preparing an electrochemically reconfigurable resistant cobalt-based metal organic framework material as in claim 3, comprising the steps of: s1, mixing cobalt (III) acetylacetonate and an organic ligand, and grinding into powder under a xenon lamp to obtain a precursor; And S2, heating the precursor in vacuum under an inert atmosphere to obtain the cobalt-based metal organic framework material.
5. 5. The method for preparing an electrochemical reconstruction resistant cobalt-based metal organic framework material according to claim 4, wherein the molar ratio of the cobalt (III) acetylacetonate to the organic ligand in the step S1 is 1:3-1:8.
6. 6. The method for preparing the cobalt-based metal organic framework material resistant to electrochemical reconstruction according to claim 4, wherein in the step S2, when the cobalt-based metal organic framework material is heated in vacuum, the vacuum degree is less than 0.05 Pa, the temperature is raised to 140-350 ℃ at the temperature raising rate of 1-10 ℃ per minute, and the temperature is kept for 1-2 hours.
7. 7. Use of a cobalt-based metal organic framework material resistant to electrochemical reconstruction according to any of claims 1-3 in electrocatalytic reactions.
8. 8. The use according to claim 7, wherein the electrocatalytic reaction comprises one of a hydrogen evolution reaction and an oxygen evolution reaction.
9. 9. The method of claim 8, wherein the electrocatalytic reaction is carried out under conditions that the pH of the electrolyte is >10, the test voltage for oxygen evolution reaction is 0.9-1.7V, the test voltage for hydrogen evolution reaction is-0.7-0V, and the scanning rate is 50V/s.

Description

Electrochemical reconstruction resistant cobalt-based metal organic framework material and preparation method and application thereof Technical Field The invention relates to the technical field of metal-organic framework materials, in particular to an electrochemical reconstruction resistant cobalt-based metal-organic framework material, and a preparation method and application thereof. Background Cobalt-based metal organic frameworks have great potential for use in electrocatalysis (oxygen evolution, hydrogen evolution) (adv. Mater. 2022, 34 (11): 2107072; coord. Chem. Rev. 2025, 523 (2): 216296). However, the cobalt-based metal organic framework can be subjected to surface or complete reconstruction in strong alkaline electrolyte and high-potential electrochemical oxidation, so that crystal transformation and structural collapse are caused, and the advantages of inheriting the metal organic framework, such as high specific surface area, abundant pore structures and the like are remarkably restrained. For example, co atoms in the metal organic framework will be converted to Co-OH (α/β -Co (OH) 2) in a basic oxygen evolution reaction, and further to Co-OOH (CoOOH) (adv. Mater. 2021, 33 (32): 2007344;Renewables 2024, 2:272-296). A number of in situ experiments demonstrated that the cobalt-based metal organic frameworks were converted to alpha/beta-Co (OH) 2 during high potential electrochemical oxidation and eventually formed either an active phase CoOOH or an inactive phase CoO (ACS catalyst 2020, 10 (1): 81-92; nano Lett 2025, 25 (29): 11484-11491). Currently, electrochemical reconstruction resistant cobalt-based metal organic frameworks remain blank in the research in the art, which results in their application as electrolyzed water catalytic materials encountering performance and stability bottlenecks. Disclosure of Invention In view of the above, the invention provides an electrochemical reconstruction resistant cobalt-based metal-organic framework material, a preparation method and application thereof, wherein the cobalt-based metal-organic framework material can serve as an active center in an electrocatalytic process and does not generate reconstruction phenomenon. The technical scheme is realized in that in the first aspect, the invention provides an electrochemical reconstruction resistant cobalt-based metal-organic framework material which is formed by coordination of trivalent cobalt and an organic ligand. Specifically, co 3+ is directly used as a main metal node for assembling the metal organic frame, so that electrochemical reconstruction of the metal organic frame is completely inhibited, the cobalt-based metal organic frame can be directly used as an active center, and efficient and stable implementation of electrocatalytic reaction is realized. Specifically, the crystal structure of the cobalt-based metal organic framework material is consistent with that of divalent cobalt/zinc of the ligand, and the crystal structure of the divalent cobalt/zinc is one or more of ZIF-67 (Co 2+ (2-methylimidazole) 2）、MAF-32（Zn2+ (2-ethylimidazole) 2) and ZIF-ana (Zn 2+ (2-propylimidazole) 2). Compared with an isomorphic metal organic framework formed by bivalent cobalt/zinc, the cobalt-based metal organic framework resistant to electrochemical reconstruction has the valence state of 3 after being detected by X-ray photoelectron spectroscopy. On the basis of the technical scheme, preferably, the salt precursor of the trivalent cobalt is cobalt (III) acetylacetonate. On the basis of the above technical scheme, preferably, the organic ligand is one or more of 2-methylimidazole, 2-ethylimidazole and 2-propylimidazole. In a second aspect, the invention provides a method for preparing an electrochemically reconstruction resistant cobalt-based metal-organic framework material, comprising the steps of: s1, mixing cobalt (III) acetylacetonate and an organic ligand, and grinding into powder under a xenon lamp to obtain a precursor; And S2, heating the precursor in vacuum under an inert atmosphere to obtain the cobalt-based metal organic framework material. Based on the above technical scheme, preferably, the molar ratio of the cobalt (III) acetylacetonate to the organic ligand in step S1 is 1:3 to 1:8. Based on the technical scheme, preferably, the inert gas in the step S2 is one of nitrogen, carbon dioxide, helium, neon, argon and krypton, and the gas flow rate is 100-300 cc/min. Based on the technical scheme, preferably, when the vacuum heating is performed in the step S2, the vacuum degree is less than 0.05 Pa, the temperature is raised to 140-350 ℃ at the temperature raising rate of 1-10 ℃ per minute, and the heat is preserved for 1-2 hours. On the basis of the technical scheme, the temperature rise temperature is preferably 260 ℃ of 2-methylimidazole, 260 ℃ of 2-ethylimidazole and 140 ℃ of 2-propylimidazole according to the organic ligand. In a third aspect, the invention provides the use of a cobalt-based metal