CN108486605A - A kind of carbon coating selenizing nickel cobalt nano material and preparation method thereof with excellent electrolysis water performance - Google Patents

Abstract

Translated fromChinese

一种具有优异电解水性能的碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料及其制备方法。所述方法包括：先将Co(NO₃)₂·6H₂O、Ni(NO₃)₂·6H₂O、聚乙烯吡咯烷酮（PVP‑K30）和对苯二甲酸溶解在N,N‑二甲基甲酰胺(DMF)和乙醇的混合溶液中，然后转移到聚四氟乙烯内衬的高压釜中，高温反应合成Co‑Ni‑MOFs材料后洗涤干燥研磨，与硒粉混合后放入管式炉中，在氮气气氛下进行高温退火处理，得到碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料。本发明获得的碳包覆的Ni_0.67Co_0.33Se₂纳米材料具有制备速度快、产率高、稳定性好等优异特性，在碱性条件下电解水催化方面具有重要的应用价值。

A carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with excellent water electrolysis performance and a preparation method thereof. The method includes: first dissolving Co(NO₃ )₂ ·6H₂ O, Ni(NO₃ )₂ ·6H₂ O, polyvinylpyrrolidone (PVP‑K30) and terephthalic acid in N,N‑dimethyl Dimethyl formamide (DMF) and ethanol mixed solution, and then transferred to a polytetrafluoroethylene-lined autoclave, high-temperature reaction to synthesize Co-Ni-MOFs materials, washed, dried and ground, mixed with selenium powder and put into a tube In the furnace, high-temperature annealing treatment is carried out under nitrogen atmosphere to obtain carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials. The carbon-coated Ni_0.67 Co_0.33 Se₂ nanometer material obtained in the present invention has excellent characteristics such as fast preparation speed, high yield and good stability, and has important application value in electrolysis of water under alkaline conditions.

Description

Translated fromChinese

一种具有优异电解水性能的碳包覆硒化镍钴纳米材料及其制备方法A carbon-coated nickel-cobalt selenide nanomaterial with excellent water electrolysis performance and its preparationpreparation method

技术领域technical field

在本发明涉及一种具有优异电解水性能的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料及其制备方法。The invention relates to a carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanometer material with excellent water electrolysis performance and a preparation method thereof.

背景技术Background technique

随着化石燃料的减少和环境污染的加剧，未来社会的发展将不得不依赖于可持续再生能源。电解水制备清洁氢燃料的方法被普遍认为是一种有前途的可持续发展解决方案。然而因为水分解过程为非自发反应，包括析氧反应（OER）和析氢反应(HER)需要非常高的过电势，电解水的实际应用有很大的局限性。目前，贵金属氧化物，如RuO₂和IrO₂，是最有效的OER电催化剂，但是其价格昂贵，储量有限等缺点严重限制了其大规模推广应用，同样的在析氢电催化反应中Pt、Pd、Rh 等贵金属的电催化活性较高，但是其成本高昂，资源有限，极大限制了其大规模商业化应用。因此，开发廉价、高效、稳定的电催化剂已成为现今电化学能源储存和转化器件发展面临的一个巨大挑战。在这方面，过渡金属硒化物、硫化物、氧化物和磷化物是最有潜力的电解水催化剂。基于非贵金属制备的的电解水催化材料中,过渡金属钴和镍因其成本低廉，储量丰富、来源广泛，良好的导电性，以及具有与铂类似的氢吸附自由能等特性使得制备廉价高效电解水催化剂成为可能。With the reduction of fossil fuels and the intensification of environmental pollution, the development of future society will have to rely on sustainable renewable energy. The method of electrolyzing water to produce clean hydrogen fuel is generally regarded as a promising sustainable solution. However, because water splitting processes are non-spontaneous reactions, including oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), which require a very high overpotential, the practical application of water electrolysis has great limitations. At present, noble metal oxides, such as RuO₂ and IrO₂ , are the most effective OER electrocatalysts, but their high price and limited reserves seriously limit their large-scale application. Similarly, Pt, Pd , Rh and other noble metals have high electrocatalytic activity, but their high cost and limited resources greatly limit their large-scale commercial application. Therefore, the development of cheap, efficient, and stable electrocatalysts has become a great challenge for the development of electrochemical energy storage and conversion devices. In this regard, transition metal selenides, sulfides, oxides, and phosphides are the most promising catalysts for electrosplitting water. Among the non-precious metal-based electrolytic water catalytic materials, the transition metals cobalt and nickel are low in cost, abundant in reserves, wide in source, good in electrical conductivity, and have hydrogen adsorption free energy similar to platinum, making it possible to prepare cheap and efficient electrolytic catalysts. Water catalysts are possible.

金属有机骨架材料（MOFs）是由有机配体与金属离子或金属簇自组装而形成的一类具有周期性网状结构的多孔配位聚合物，因此可以通过对金属中心原子和机配体的选择、修饰来设计出不同结构的MOFs材料,而且有机配体在高温退火过程中能直接转化为多孔碳、无定形碳，形成的碳包裹的纳米颗粒可以有效提高稳定性，再加上其孔结构有序可调、比表面积大、结构多样性等诸多优异特性，因此可先设计合成功能化的MOFs作为牺牲模板，不用添加额外碳源直接通过高温退火过程来制备具有良好的电催化性能多孔碳/金属氧化物材料，这为我们以MOFs材料为前驱体制备碳包覆钴镍硒化物电解水催化剂提供了理论支持。Metal-organic frameworks (MOFs) are a class of porous coordination polymers with a periodic network structure formed by the self-assembly of organic ligands and metal ions or metal clusters. Select and modify to design MOFs materials with different structures, and the organic ligands can be directly converted into porous carbon and amorphous carbon during the high temperature annealing process, and the formed carbon-wrapped nanoparticles can effectively improve the stability. Orderly and adjustable structure, large specific surface area, structural diversity and many other excellent properties, so functionalized MOFs can be designed and synthesized as sacrificial templates first, and porous materials with good electrocatalytic properties can be prepared directly through high-temperature annealing process without adding additional carbon sources. Carbon/metal oxide materials, which provide theoretical support for us to use MOFs materials as precursors to prepare carbon-coated cobalt-nickel-selenide electrolytic water catalysts.

发明内容Contents of the invention

本发明要解决的技术问题为克服现有过渡金属硒化物的制备技术中的不足之处，发展一种具有优异电解水性能的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料及其制备方法。The technical problem to be solved in the present invention is to overcome the deficiencies in the existing transition metal selenide preparation technology and develop a carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with excellent water electrolysis performance and its preparation method.

本发明中碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料的典型合成过程是将适量Co(NO₃)₂·6H₂O、Ni(NO₃)₂·6H₂O、聚乙烯吡咯烷酮(PVP-K30)和对苯二甲酸溶解在N,N-二甲基甲酰胺(DMF)和乙醇的混合溶液中，然后转移到聚四氟乙烯内衬的高压釜中，高温反应合成Co-Ni-MOFs材料后洗涤干燥并研磨成粉末，与硒粉混合后放入管式炉中，高温退火，最终制备出碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料。The typical synthesis process of carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials in the present invention is to mix an appropriate amount of Co(NO₃ )₂ ·6H₂ O, Ni(NO₃ )₂ ·6H₂ O, poly Vinylpyrrolidone (PVP-K30) and terephthalic acid were dissolved in a mixed solution of N,N-dimethylformamide (DMF) and ethanol, and then transferred to a polytetrafluoroethylene-lined autoclave for high-temperature reaction synthesis The Co-Ni-MOFs material was washed, dried and ground into powder, mixed with selenium powder, put into a tube furnace, annealed at high temperature, and finally prepared carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials .

本发明中所述的一种具有优异电解水性能的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料及其制备方法，包括以下具体步骤：A carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with excellent water electrolysis performance and its preparation method described in the present invention comprise the following specific steps:

（1）将0.1746克Co(NO₃)₂·6H₂O和0.3489克Ni(NO₃)₂·6H₂O加入到的9.375毫升N,N-二甲基甲酰胺(DMF)和5.625毫升乙醇的混合溶液中，再加入0.36克聚乙烯吡咯烷酮(PVP-K30)和0.1995克对苯二甲酸，搅拌溶解至均匀溶液，将此混合溶液转移到高压釜中，在120摄氏度下保温24小时合成Co-Ni-MOFs材料后取出室温下冷却。(1) Add 0.1746 g of Co(NO₃ )₂ 6H₂ O and 0.3489 g of Ni(NO₃ )₂ 6H₂ O to 9.375 ml of N,N-dimethylformamide (DMF) and 5.625 ml of ethanol In the mixed solution, add 0.36 grams of polyvinylpyrrolidone (PVP-K30) and 0.1995 grams of terephthalic acid, stir and dissolve to a uniform solution, transfer this mixed solution to an autoclave, and synthesize Co at 120 degrees Celsius for 24 hours. -Ni-MOFs material was taken out and cooled at room temperature.

（2）把步骤（1）所得Co-Ni-MOFs材料分别用去离子水和乙醇洗涤两遍，80摄氏度下真空干燥2小时，冷却后研磨成粉末备用。(2) The Co-Ni-MOFs material obtained in step (1) was washed twice with deionized water and ethanol respectively, dried in vacuum at 80 degrees Celsius for 2 hours, cooled and ground into powder for later use.

（3）称取0.1克步骤（2）所得粉末和0.5克硒粉，混合均匀后放入管式炉中，并通入氮气进行保护，随后进行高温退火处理，其中升温速率为10摄氏度/分钟，退火温度为450摄氏度。(3) Weigh 0.1 g of the powder obtained in step (2) and 0.5 g of selenium powder, mix them evenly, put them into a tube furnace, and pass in nitrogen gas for protection, and then perform high-temperature annealing treatment, wherein the heating rate is 10 degrees Celsius/minute , the annealing temperature is 450 degrees Celsius.

与现有技术相比，本发明所提供的一种具有优异电解水性能的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料的制备方法至少具有以下有益效果：Compared with the prior art, the preparation method of a carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with excellent water electrolysis performance provided by the present invention has at least the following beneficial effects:

（1）本发明实施例所提供一种具有优异电解水性能的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料的制备方法最大优点在于原料价格便宜、来源广泛、制备过程简单；(1) The preparation method of a carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with excellent water electrolysis performance provided by the embodiment of the present invention has the biggest advantages of cheap raw materials, wide sources, and simple preparation process ;

（2）本发明实施例所提供的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料产量高、单分散性好，能够在室温条件下长时间保存；(2) The carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials provided by the examples of the present invention have high yield and good monodispersity, and can be stored at room temperature for a long time;

（3）本发明实施例所提供的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料具有比表面积大、活性位点多、易吸附反应物等优点；(3) The carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials provided in the examples of the present invention have the advantages of large specific surface area, many active sites, and easy adsorption of reactants;

（4）本发明实施例所提供一种具有电解水性能的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料的制备方法仅需反应釜、石英舟、管式炉、烘箱等一些普通设备，工艺过程简单且易于操作；(4) The preparation method of a carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with electrolytic water performance provided by the embodiment of the present invention only needs a reaction kettle, a quartz boat, a tube furnace, an oven, etc. Some common equipment, the process is simple and easy to operate;

（5）本发明实施例所提供的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料对碱性环境中电解水具有优异的催化活性，同时具有良好的稳定性。(5) The carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials provided by the examples of the present invention have excellent catalytic activity for electrolyzing water in an alkaline environment, and have good stability.

附图说明Description of drawings

图1a为采用Sirion 200场发射扫描电子显微镜对碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料拍摄得到的照片，图1b为其高分辨透射电子显微镜（HRTEM）照片，图2为Ni_0.67Co_0.33Se₂碳（C）、镍（Ni）、钴（Co）和硒（Se）元素的面分布图（EDX mapping），由此可知，Ni_0.67Co_0.33Se₂被均匀地包覆在碳层中。Figure 1a is a photo of carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials taken with a Sirion 200 field emission scanning electron microscope, and Figure 1b is a high-resolution transmission electron microscope (HRTEM) photo, Figure 2 is the surface distribution map (EDX mapping) of Ni_0.67 Co_0.33 Se₂ carbon (C), nickel (Ni), cobalt (Co) and selenium (Se). It can be seen that Ni_0.67 Co_0.33 Se₂ is uniformly covered Covered in carbon layer.

图3为Ni_0.67Co_0.33Se₂纳米材料的X-射线衍射图谱，由图可以看出：本发明制备的碳包覆的Ni_0.67Co_0.33Se₂纳米材料，其衍射峰位于NiSe₂ 和CoSe₂的标准衍射峰之间，并且没有峰的分裂，这进一步说明本发明制备的确实为碳包覆的Ni_0.67Co_0.33Se₂纳米材料。Fig. 3 is the X-ray diffraction pattern of Ni_0.67 Co_0.33 Se₂ nanomaterials, as can be seen from the figure: the Ni_0.67 Co_0.33 Se₂ nanomaterials coated with carbon prepared by the present invention, its diffraction peaks are located at NiSe₂ and CoSe₂ between the standard diffraction peaks, and there is no splitting of the peaks, which further illustrates that the present invention is indeed a carbon-coated Ni_0.67 Co_0.33 Se₂ nanomaterial.

图4-6是在辰华760e电化学测试系统中，对涂在泡沫镍（NF）上的碳包覆的Ni_0.67Co_0.33Se₂纳米材料进行测试得到的电化学图谱，命名为Ni_0.67Co_0.33Se₂/NF。图4a是泡沫镍（NF）和Ni_0.67Co_0.33Se₂/NF析氢的极化曲线，扫描速率为5毫伏/秒（mV/s），图4b是由图4a转化而来的塔菲尔曲线；图5a是泡沫镍（NF）和Ni_0.67Co_0.33Se₂/NF析氧的极化曲线，扫描速率为5毫伏/秒（mV/s），图5b是由图5a转化而来的塔菲尔曲线；图6a为Ni_0.67Co_0.33Se₂/NF全解水的极化曲线，图6b为稳定性测试图谱,说明所制备的Ni_0.67Co_0.33Se₂不但具有优异的催化活性而且循环1000圈之后仍然具有较好的稳定性。图4a、5a、6a和6b的横坐标为Potential/Vvs.RHE（即电极电势，单位为V），纵坐标为(j/mA cm^-2)（即电流密度，单位为mA cm^-2）；图4b和5b的横坐标为电流密度的Log值即Log(j/mA cm^-2)，纵坐标为Overpotential(V)（即电极电势，单位为V）。Figure 4-6 is the electrochemical spectrum obtained by testing the carbon-coated Ni_0.67 Co_0.33 Se₂ nanomaterial coated on nickel foam (NF) in the Chenhua 760e electrochemical test system, named Ni_0.67 Co_0.33 Se₂ /NF. Figure 4a is the polarization curves of nickel foam (NF) and Ni_0.67 Co_0.33 Se₂ /NF for hydrogen evolution at a scan rate of 5 millivolts/second (mV/s), and Figure 4b is the Tafel transformed from Figure 4a Curve; Figure 5a is the polarization curve of nickel foam (NF) and Ni_0.67 Co_0.33 Se₂ /NF oxygen evolution, the scan rate is 5 millivolts/second (mV/s), Figure 5b is converted from Figure 5a Tafel curve; Figure 6a is the polarization curve of Ni_0.67 Co_0.33 Se₂ /NF total water splitting, and Figure 6b is the stability test spectrum, indicating that the prepared Ni_0.67 Co_0.33 Se₂ not only has excellent catalytic activity but also cycle It still has good stability after 1000 laps. The abscissa of Figures 4a, 5a, 6a and 6b is Potential/Vvs.RHE (that is, the electrode potential in V), and the ordinate is (j/mA cm^-2 ) (that is, the current density in mA cm^-2 ) ; The abscissa in Figures 4b and 5b is the Log value of the current density, that is, Log(j/mA cm^-2 ), and the ordinate is Overpotential (V) (that is, the electrode potential, in V).

具体实施方式Detailed ways

首先准备本发明用到的Co(NO₃)₂·6H₂O、Ni(NO₃)₂·6H₂O、N,N-二甲基甲酰胺(DMF)、乙醇、聚乙烯吡咯烷酮(PVP-K30)和对苯二甲酸；随后分别将Co(NO₃)₂·6H₂O、Ni(NO₃)₂·6H₂O、PVP-K30和对苯二甲酸溶解到DMF和乙醇的混合溶液中；溶液搅拌均匀后转移至高压釜中高温反应，反应结束后将合成的Co-Ni-MOFs材料洗涤干燥并研磨；最后与硒粉混合经高温退火得到碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料。First prepare Co(NO₃ )₂ ·6H₂ O, Ni(NO₃ )₂ ·6H₂ O, N,N-dimethylformamide (DMF), ethanol, polyvinylpyrrolidone (PVP- K30) and terephthalic acid; then Co(NO₃ )₂ 6H₂ O, Ni(NO₃ )₂ 6H₂ O, PVP-K30 and terephthalic acid were dissolved in a mixed solution of DMF and ethanol, respectively After the solution is stirred evenly, it is transferred to an autoclave for high-temperature reaction. After the reaction, the synthesized Co-Ni-MOFs material is washed, dried and ground; finally mixed with selenium powder and annealed at high temperature to obtain carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials.

下面结合具体实施实例对本发明的内容作进一步详细说明，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明的实施例，本领域普通技术人员在没有付出创造性劳动前提下所获得的所有其他实施例，都属于本发明的保护范围。The content of the present invention will be further described in detail below in conjunction with specific implementation examples. Apparently, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

实施例1Example 1

一种具有优异电解水性能的碳包覆硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料的制备方法包含以下步骤：A method for preparing a carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with excellent water electrolysis performance comprises the following steps:

（1）将0.1746克Co(NO₃)₂·6H₂O和0.3489克Ni(NO₃)₂·6H₂O加入到的9.375毫升N,N-二甲基甲酰胺(DMF)和5.625毫升乙醇的混合溶液中，再加入0.36克聚乙烯吡咯烷酮(PVP-K30)和0.1995克对苯二甲酸，搅拌溶解至均匀溶液，将此混合溶液转移到水热釜中，在120摄氏度下保温24小时合成Co-Ni-MOFs材料取出室温下冷却。(1) Add 0.1746 g of Co(NO₃ )₂ 6H₂ O and 0.3489 g of Ni(NO₃ )₂ 6H₂ O to 9.375 ml of N,N-dimethylformamide (DMF) and 5.625 ml of ethanol Add 0.36 grams of polyvinylpyrrolidone (PVP-K30) and 0.1995 grams of terephthalic acid to the mixed solution, stir and dissolve to a uniform solution, transfer the mixed solution to a hydrothermal kettle, and synthesize it at 120 degrees Celsius for 24 hours The Co-Ni-MOFs material was taken out and cooled at room temperature.

（2）将步骤（1）所得Co-Ni-MOFs材料分别用去离子水和乙醇洗涤两遍，80摄氏度真空干燥2小时，冷却后研磨成粉末备用。(2) The Co-Ni-MOFs material obtained in step (1) was washed twice with deionized water and ethanol respectively, dried in vacuum at 80 degrees Celsius for 2 hours, cooled and ground into powder for later use.

（3）称取0.1克步骤（2）所得粉末和0.5克硒粉，混合均匀后放入管式炉中，并通入氮气进行保护，随后进行高温退火处理，其中升温速率为10摄氏度/分钟，退火温度为450摄氏度。(3) Weigh 0.1 g of the powder obtained in step (2) and 0.5 g of selenium powder, mix them evenly, put them into a tube furnace, and pass in nitrogen gas for protection, and then perform high-temperature annealing treatment, wherein the heating rate is 10 degrees Celsius/minute , the annealing temperature is 450 degrees Celsius.

以上所述，仅为本发明较佳的具体实施方式，但本发明的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本发明揭露的技术范围内，可轻易想到的变化或替换，都应涵盖在本发明的保护范围之内。因此，本发明的保护范围应该以权利要求书的保护范围为准。The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of changes or modifications within the technical scope disclosed in the present invention. Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (3)

Translated fromChinese

1.一种具有优异电催化性能的碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料的制备方法，其特征在于：1. A method for preparing carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials with excellent electrocatalytic properties, characterized in that:制备过程可分为两步，先合成Co-Ni-MOFs材料，再经过高温退火硒化过程；The preparation process can be divided into two steps, the Co-Ni-MOFs material is first synthesized, and then undergoes a high-temperature annealing and selenization process;（1）制备出碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料为球形，大小约1微米左右；(1) Prepare carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials in a spherical shape with a size of about 1 micron;（2）制备出碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料，Ni元素和Co元素比例为2:1，其比例可通过合成MOFs前驱体时的投料比调控；(2) Prepare carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials, the ratio of Ni to Co is 2:1, and the ratio can be regulated by the feed ratio when synthesizing MOFs precursor;（3）碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料在室温环境中具有很好的稳定性；(3) Carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials have good stability at room temperature;（4）碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料在碱性条件下具有优异的电解水催化活性，同时具有非常出色的稳定性。(4) Carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterials have excellent catalytic activity for electrolysis of water under alkaline conditions, and also have excellent stability.2.一种权利要求1所述的一种具有优异电催化性能的碳包覆的硒化镍钴（Ni_0.67Co_0.33Se₂）纳米材料及其制备方法，其特征是包括以下步骤：2. A carbon-coated nickel-cobalt selenide (Ni_0.67 Co_0.33 Se₂ ) nanomaterial with excellent electrocatalytic performance as claimed in claim 1 and its preparation method, characterized in that it comprises the following steps:（1）将0.1746克Co(NO₃)₂·6H₂O和0.3489克Ni(NO₃)₂·6H₂O加入到的9.375毫升N,N-二甲基甲酰胺(DMF)和5.625毫升乙醇的混合溶液中，再加入0.36克聚乙烯吡咯烷酮(PVP-K30)和0.1995克对苯二甲酸，搅拌溶解至均匀溶液，将此混合溶液转移到水热釜中，在120摄氏度下保温24小时合成Co-Ni-MOFs材料后取出后室温下冷却；(1) Add 0.1746 g of Co(NO₃ )₂ 6H₂ O and 0.3489 g of Ni(NO₃ )₂ 6H₂ O to 9.375 ml of N,N-dimethylformamide (DMF) and 5.625 ml of ethanol Add 0.36 grams of polyvinylpyrrolidone (PVP-K30) and 0.1995 grams of terephthalic acid to the mixed solution, stir and dissolve to a uniform solution, transfer the mixed solution to a hydrothermal kettle, and synthesize it at 120 degrees Celsius for 24 hours After the Co-Ni-MOFs material is taken out, it is cooled at room temperature;（2）将步骤（1）所得混合溶液分别用去离子水和乙醇洗涤两遍，80℃真空干燥2小时，冷却后研磨成粉末备用；(2) The mixed solution obtained in step (1) was washed twice with deionized water and ethanol respectively, dried in vacuum at 80°C for 2 hours, cooled and ground into powder for later use;（3）称取0.1克步骤（2）所得粉末和0.5克硒粉，混合均匀后放入管式炉中，并通入氮气进行保护，随后进行高温退火处理，其中升温速率为10摄氏度/分钟，退火温度为450摄氏度，根据退火温度将所得样品命名为Ni_0.67Co_0.33Se₂。(3) Weigh 0.1 g of the powder obtained in step (2) and 0.5 g of selenium powder, mix them evenly, put them into a tube furnace, and pass in nitrogen gas for protection, and then perform high-temperature annealing treatment, wherein the heating rate is 10 degrees Celsius/minute , the annealing temperature was 450 degrees Celsius, and the obtained sample was named Ni_0.67 Co_0.33 Se₂ according to the annealing temperature.3.一种具有优异电解水析氢性能的碳包覆的Ni_0.67Co_0.33Se₂纳米材料，其特征在于：在电流密度为10 mA cm^-2时，析氢过电势只有143 mV, 塔菲尔斜率为114.8 mV dec^-1；析氧过电势只有311 mV塔菲尔斜率为24.9 mV dec^-1；全解水过电势只有1.69 V，具有优异的催化活性。3. A carbon-coated Ni_0.67 Co_0.33 Se₂ nanomaterial with excellent hydrogen evolution performance in water electrolysis, characterized in that: when the current density is 10 mA cm^-2 , the hydrogen evolution overpotential is only 143 mV, and the Tafel slope It is 114.8 mV dec^-1 ; the oxygen evolution overpotential is only 311 mV, and the Tafel slope is 24.9 mV dec^-1 ; the total water splitting overpotential is only 1.69 V, showing excellent catalytic activity.