阅读说明：本技术 一种二硒化钴/氮掺杂碳纳米材料复合电极催化材料及其制备方法、应用 (Cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material and preparation method and application thereof ) 是由 曹澥宏 张琳 刘文贤 施文慧 于 2019-08-19 设计创作，主要内容包括：本发明涉及复合材料技术领域,为解决现有锌空电池的电极催化材料价格昂贵、催化活性不高的问题,提供了一种二硒化钴/氮掺杂碳纳米材料复合电极催化材料及其制备方法、应用,包括以下步骤：(1)在经过亲水化处理的碳布上生长Co-MOF；(2)通过CVD法生长氮掺杂碳纳米材料,得到Co/氮掺杂碳纳米材料；所述氮掺杂碳纳米材料为氮掺杂碳纳米管和氮掺杂碳纳米片的两种组合；(3)硒化处理,制得二硒化钴/氮掺杂碳纳米材料复合电极催化材料。本发明的复合材料保留了以三角片状MOF晶体为模板得到的二硒化钴多孔框架/碳纳米片阵列的结构完整性,兼具了碳纳米管和二硒化钴多孔框架的优异性能,在吸附、传感、储能、催化等领域中具有广阔的应用前景。(The invention relates to the technical field of composite materials, and provides a cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material and a preparation method and application thereof, aiming at solving the problems of high price and low catalytic activity of the electrode catalytic material of the existing zinc-air battery, wherein the preparation method comprises the following steps: (1) growing Co-MOF on the carbon cloth subjected to hydrophilization treatment; (2) growing a nitrogen-doped carbon nano material by a CVD (chemical vapor deposition) method to obtain a Co/nitrogen-doped carbon nano material; the nitrogen-doped carbon nano material is a combination of a nitrogen-doped carbon nano tube and a nitrogen-doped carbon nano sheet; (3) selenizing to prepare the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material. The composite material disclosed by the invention reserves the structural integrity of a cobalt diselenide porous frame/carbon nanosheet array obtained by taking a triangular flaky MOF crystal as a template, has the excellent performances of a carbon nanotube and the cobalt diselenide porous frame, and has a wide application prospect in the fields of adsorption, sensing, energy storage, catalysis and the like.)

1. A preparation method of a cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material is characterized by comprising the following steps:

(1) growing Co-MOF in situ on the carbon cloth subjected to hydrophilization treatment by a hydrothermal method;

(2) growing a nitrogen-doped carbon nano material on the carbon cloth treated in the step (1) by a CVD (chemical vapor deposition) method to obtain a Co/nitrogen-doped carbon nano material; the nitrogen-doped carbon nano material is a combination of a nitrogen-doped carbon nano tube and a nitrogen-doped carbon nano sheet;

(3) and (3) selenizing the Co/nitrogen-doped carbon nano material grown on the surface of the carbon cloth in the step (2) to obtain the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material.

2. The method for preparing a cobalt diselenide/nitrogen-doped carbon nanomaterial composite electrode catalytic material according to claim 1, wherein in the step (2), the CVD method specifically comprises: firstly introducing nitrogen to exhaust air, heating to 300-600 ℃ at the speed of 3-5 ℃/min, introducing ethanol and hydrogen to calcine for 0.1-1 h, then keeping for 1-3 h under the nitrogen atmosphere, and finally naturally cooling to obtain the Co/nitrogen-doped carbon nanomaterial.

3. The preparation method of the cobalt diselenide/nitrogen-doped carbon nanomaterial composite electrode catalytic material as claimed in claim 1, wherein in the step (3), the selenization treatment method comprises: selenium powder is added into the Co/nitrogen-doped carbon nano material, and the Co/nitrogen-doped carbon nano material is calcined for 1-20 hours at the temperature of 300-600 ℃.

4. The preparation method of the cobalt diselenide/nitrogen-doped carbon nanomaterial composite electrode catalytic material as claimed in claim 3, wherein the mass ratio of the selenium powder to the Co/nitrogen-doped carbon nanomaterial is 1: (8-10).

5. The preparation method of the cobalt diselenide/nitrogen-doped carbon nanomaterial composite electrode catalytic material as claimed in claim 1, wherein in the step (2), the length of the nitrogen-doped carbon nanotube is 50-200 nm.

6. The preparation method of the cobalt diselenide/nitrogen-doped carbon nanomaterial composite electrode catalytic material as claimed in claim 1, wherein in the step (2), the nitrogen-doped carbon nanosheet is of a triangular structure, and the side length of the nitrogen-doped carbon nanosheet is controlled to be 2-4 μm.

7. The preparation method of the cobalt diselenide/nitrogen-doped carbon nanomaterial composite electrode catalytic material of claim 1, wherein in the step (1), the Co-MOF is in a two-dimensional triangular structure.

8. A cobalt diselenide/nitrogen doped carbon nanomaterial composite electrode catalytic material prepared by the method of any one of claims 1 to 7.

9. The application of the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material prepared by the method in any one of claims 1 to 7 in a zinc-air battery.

Technical Field

The invention relates to the technical field of composite materials, in particular to a cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material, and a preparation method and application thereof.

Background

Nowadays, as the global energy consumption and demand are drastically increased due to the continuous growth of economy and population, the development and utilization of new energy sources are urgently needed in order to reduce the gradual depletion of fossil fuels and the accompanying climate problems. The zinc-air battery is used as a novel energy conversion device, has the advantages of high energy density, environmental friendliness, long service life, high energy conversion efficiency, low price and the like, and is widely concerned by people.

Among them, the electrode catalytic material of the zinc-air battery is a key factor determining the performance and cost of the battery. Currently, the most commonly used and effective catalyst is a noble metal catalyst, but its wide application in industry is limited due to its high price and small storage amount. Therefore, it is very important to develop an electrode material with low cost and high catalytic activity.

Metal-organic framework compounds (MOFs), are formed by coordination of organic ligands with metal ions/clusters through complexation. MOF materials have great potential in gas storage, chemical separation, selective catalysis, and drug delivery. The intrinsically porous structure of MOFs facilitates electrolyte penetration and ion transport, and the use of MOFs as MOF-derived materials obtained from sacrificial templates is more promising as electrode materials, since they mostly inherit not only the porous structure of the MOF precursor, but also exhibit good electrical conductivity provided by carbon. Therefore, the MOF is used as a precursor, and the obtained porous selenide/carbon composite material has a good application prospect in clean energy.

The Chinese patent literature discloses a cobalt selenide/carbon sodium ion battery composite cathode material and a preparation method and application thereof, wherein the publication number is CN105789584A, the cobalt selenide/carbon composite material prepared by the invention has good dispersibility and a uniform nano rod-shaped structure, and has higher charge-discharge specific capacity, good rate capability and cycling stability as a sodium ion battery cathode material, but the composite cathode material has lower specific surface area and poor bending resistance, and cannot be applied to flexible batteries.

Disclosure of Invention

The invention provides a preparation method of a cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material, aiming at overcoming the problems of high price and low catalytic activity of the electrode catalytic material of the existing zinc-air battery.

The invention also provides the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material prepared by the method, the structural integrity of a cobalt diselenide porous frame/carbon nano sheet array obtained by taking the triangular flaky MOF crystal as a template is reserved, the excellent performances of the carbon nano tube and the cobalt diselenide porous frame are combined, and compared with the traditional zinc-air battery electrode catalytic material, the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material has the advantages of high catalytic activity, low price, excellent conductivity, good flexibility and the like.

The invention also provides application of the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material in a zinc-air battery.

In order to achieve the purpose, the invention adopts the following technical scheme:

a preparation method of a cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material comprises the following steps:

(1) growing Co-MOF in situ on the carbon cloth subjected to hydrophilization treatment by a hydrothermal method;

(2) growing a nitrogen-doped carbon nano material on the carbon cloth treated in the step (1) by a CVD (chemical vapor deposition) method to obtain a Co/nitrogen-doped carbon nano material; the nitrogen-doped carbon nano material is a combination of a nitrogen-doped carbon nano tube and a nitrogen-doped carbon nano sheet;

(3) and (3) selenizing the Co/nitrogen-doped carbon nano material grown on the surface of the carbon cloth in the step (2) to obtain the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material.

According to the invention, the Co-MOF sheet is grown on the carbon cloth subjected to hydrophilization treatment by a hydrothermal method, and the sheet-shaped array structure cobalt diselenide porous frame/nitrogen-doped carbon nano material composite electrode catalytic material is prepared after two-step calcination.

Preferably, the hydrophilization treatment method of the carbon cloth comprises the following steps: the carbon cloth is sequentially soaked in acetone (99.5%), 10% hydrochloric acid and ethanol (99.7%), then washed to be neutral by deionized water, dried for 24 hours in vacuum at 60 ℃ and finally subjected to plasma hydrophilization for later use.

Preferably, in the step (2), the CVD method specifically includes: firstly introducing nitrogen to exhaust air, heating to 300-600 ℃ at the speed of 3-5 ℃/min, introducing ethanol and hydrogen to calcine for 0.1-1 h, then keeping for 1-3 h under the nitrogen atmosphere, and finally naturally cooling to obtain the Co/nitrogen-doped carbon nanomaterial.

Preferably, in step (3), the selenization process includes: selenium powder is added into the Co/nitrogen-doped carbon nano material, and the Co/nitrogen-doped carbon nano material is calcined for 1-20 hours at the temperature of 300-600 ℃.

Preferably, the mass ratio of the selenium powder to the Co/nitrogen-doped carbon nano material is 1: (8-10).

Preferably, in the step (2), the length of the nitrogen-doped carbon nanotube is 50 to 200 nm.

Preferably, in the step (2), the nitrogen-doped carbon nanosheet is of a triangular structure, and the side length of the nitrogen-doped carbon nanosheet is controlled to be 2-4 μm.

Preferably, in step (1), the Co-MOF has a two-dimensional triangular structure.

The cobalt diselenide porous frame/nitrogen-doped carbon nano material composite electrode catalytic material uniformly grows on the surface of carbon cloth, specifically, a two-dimensional triangular Co-MOF nanosheet array uniformly grows on the surface of the carbon cloth, then a nitrogen-doped carbon nanosheet and a nitrogen-doped carbon nano tube grow through a CVD (chemical vapor deposition) method, and the obtained Co/nitrogen-doped carbon nano material is subjected to selenylation treatment to obtain the cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material. The material has a porous structure, the integrity of the triangular structure of the MOF sheet is kept in the synthesis process, the material has the excellent performances of a carbon nano tube and a cobalt diselenide porous frame, the specific surface area of the array-shaped triangular two-dimensional nano sheet and the one-dimensional carbon tube structure is increased, and more active sites are exposed in the two-dimensional porous structure, so that the material is beneficial to electrocatalysis reaction. In addition, the composite material has a multi-level pore structure, specifically comprises micropores of the two-dimensional MOF, open pores among triangular carbon nanosheets in the array and macropores of the carbon cloth substrate, and is favorable for infiltration of electrolyte and separation of gas. The material can simultaneously play the advantages of the carbon nano tube and the porous cobalt diselenide in the fields of adsorption, sensing, energy storage, catalysis and the like, and the flaky array structure cobalt diselenide porous frame/nitrogen-doped carbon nano tube/carbon nano sheet composite material grows on carbon cloth and has certain flexibility. Therefore, the method has good application prospect in flexible electronic devices.

Preferably, the CVD method is specifically: firstly introducing nitrogen to exhaust air, heating to 300-600 ℃ at the speed of 5 ℃/min, introducing ethanol and hydrogen to calcine for 0.1-1 h, then keeping for 1-3 h under the nitrogen atmosphere, and finally naturally cooling to obtain the Co/nitrogen-doped carbon nanomaterial.

Preferably, the selenization treatment method comprises the following steps: selenium powder is added into the Co/nitrogen-doped carbon nano material, and the Co/nitrogen-doped carbon nano material is calcined for 1-20 hours at the temperature of 300-600 ℃.

Preferably, the mass ratio of the selenium powder to the Co/nitrogen-doped carbon nano material is 1: (8-10).

The composite electrode catalytic material grows on the surface of carbon cloth subjected to hydrophilization treatment, and is a multistage pore structure compounded by cobalt diselenide with a two-dimensional triangular structure, nitrogen-doped carbon nanotubes growing on the surface of the cobalt diselenide and nitrogen-doped nanosheets.

The cobalt diselenide/nitrogen-doped carbon nano material composite electrode catalytic material prepared by any one of the methods is applied to a zinc-air battery.

Therefore, the invention has the following beneficial effects:

(1) the mass production or the industrial production can be realized;

(2) the preparation method has mild conditions, simple operation, controllable structure and uniform component distribution;

(3) the composite electrode catalytic material reserves the structural integrity of a cobalt diselenide porous framework/carbon nanosheet array obtained by taking triangular flaky MOF crystals as templates, and has the excellent performances of carbon nanotubes and the cobalt diselenide porous framework.

Drawings

FIG. 1 is an SEM and TEM image of the product obtained in example 1: Co-MOF (1a), Co/nitrogen-doped carbon nano tube/nitrogen-doped carbon nano sheet (1b), and cobalt diselenide/nitrogen-doped carbon nano tube/nitrogen-doped carbon nano sheet composite electrode catalytic material (1c, 1e, 1d, 1 f).

Fig. 2 is a cycle performance diagram of a zinc-air battery prepared by using the cobalt diselenide/nitrogen-doped carbon nanotube/nitrogen-doped carbon nanosheet prepared in example 1 as a zinc-air battery composite electrode catalytic material.

Fig. 3 is a performance display diagram of a flexible zinc-air battery prepared by using the cobalt diselenide/nitrogen-doped carbon nanotube/nitrogen-doped carbon nanosheet prepared in example 1 as a zinc-air battery composite electrode catalytic material.

Detailed Description

The technical solution of the present invention is further specifically described below by way of specific examples.

In the present invention, all the equipment and materials are commercially available or commonly used in the art, and the methods in the following examples are conventional in the art unless otherwise specified.