CN112295581A - Electrocatalyst material and application thereof - Google Patents

Abstract

The invention provides an electrocatalyst material whose catalytically active component is Ni₂Mo₃N、Ni₂Mo₃One or more of N composite material, the Ni₂Mo₃N is cubic phase Ni₂Mo₃N; ni of the invention₂Mo₃The N nano-particle catalyst achieves the aim of catalytic activity and stabilityThe higher level; the nitrogen source for preparing the nitride is derived from urea, and ammonia gas with strong corrosivity is not used as a nitriding atmosphere, so that the method is green and environment-friendly; the sol precursor is directly put at high temperature for nitridation reaction, so that the crystallization and solidification process is avoided, and the method is favorable for large-scale industrial production.

Description

Electrocatalyst material and application thereof

Technical Field

The invention relates to an electrocatalyst material and applications thereof.

Background

Energy is an important material basis for economic growth and social development. Every epoch-like transition of energy technology is accompanied with the leap of productivity, and the great development and progress of the whole human society are promoted. With the increase of population and the rapid development of economy, the global demand for energy is increasing. Energy crisis and environmental issues have become the focus of important and scientific research in politics, economy, military, diplomatic and other areas of today's international society. The green renewable energy technology is explored and developed, and the dependence on fossil fuel can be fundamentally removed. Therefore, more and more scientific researchers are beginning to search for and develop sustainable energy devices, such as fuel cells, solar cells, metal-air batteries, lithium ion batteries, super capacitors, and the like, without losing their power. The hydrogen energy is used as green energy, has the advantages of wide source, high specific energy, recycling and the like, is a creditable clean energy star, and the hydrogen production by water electrolysis becomes the main hydrogen energy mode in the future. When the water is electrolyzed to produce hydrogen, the anode can generate oxygen evolution reaction along with hydrogen evolution of the cathode, and the over-high anode overpotential is the primary factor and the core problem of the energy consumption of the water electrolysis for producing the hydrogen. However, Ir, Ru and their oxide anode catalysts with high catalytic activity are expensive, scarce in resources and poor in stability. This has led to the active search for the development of a noble metal-substituted catalyst which is excellent in performance and low in cost. The non-noble transition metal nitride often has unsaturated d electron orbitals, excellent corrosion resistance and high electrical conductivity, and is expected to replace noble metals in the application and development of electrochemical catalysis through reasonable design regulation and control of the structure/composition and the like.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of the prior art: an electrocatalyst material and its uses are provided. The applicant of the present invention has found that cubic phase Ni is a problem in the prior art₂Mo₃The N material has excellent oxygen evolution electrocatalytic performance and can replace a noble metal catalyst (IrO) in electrolytic water₂/CB) as anodeThe catalyst has the characteristics of low cost, high activity and high stability.

The technical solution of the invention is as follows: an electrocatalyst material with Ni as its catalytically active component₂Mo₃N、Ni₂Mo₃One or more of N composite materials.

Preferably, the Ni is₂Mo₃N is cubic phase Ni₂Mo₃N。

The cubic phase Ni₂Mo₃The preparation method of N comprises the following steps:

1) dissolving nickel chloride and molybdenum chloride in an ethanol solution to obtain a clear solution;

2) adding a nitrogen source into the clear solution obtained in the step 1), and standing to obtain a colloidal precursor;

3) calcining the precursor obtained in the step 2) in inert gas at the temperature of more than 500 ℃ to obtain cubic phase Ni₂Mo₃And N nano-particles.

Preferably, the ethanol solution is absolute ethanol, and the nitrogen source is a nitrogen-containing organic substance.

The nitrogen-containing organic matter is urea, and the inert gas is nitrogen or argon.

The application of the electrocatalyst material comprises all electrocatalytic applications including water electrolysis and metal-air batteries containing oxygen evolution.

The invention discloses a ternary transition metal nitride Ni₂Mo₃A preparation method of N nano-particles and application of electrocatalytic oxygen evolution. The method uses two metal chlorides as metal sources and urea as a nitrogen source, and the pure-phase Ni can be obtained by heating in an inert atmosphere₂Mo₃An N-nitride catalyst. The precursor used for high-temperature nitridation is sol-like and can be obtained by dissolving metal chloride and urea in absolute ethyl alcohol and standing for a certain time. Ni obtained after nitriding₂Mo₃The N particles have uniform nano-morphology, can be used as an electrocatalyst for catalyzing the oxygen evolution reaction, and have higher catalytic activity and stability. The synthesis method has controllable synthesis components and is nanoElectrically oxygen evolving catalytic materials which are structurally controllable and have a high specific surface area and good durability offer great possibilities. The method is simple and easy to implement, low in cost, green and environment-friendly, is suitable for large-scale production, and shows superior commercial IrO in electrochemical oxygen evolution reaction₂The excellent activity and stability of the/CB catalyst have good industrial application prospect.

The invention has the beneficial effects that: compared with the prior art, the method of the invention has obvious differences:

1) ni obtained by the method of the invention₂Mo₃The N nano-particle catalyst reaches a higher level in both catalytic activity and stability;

2) the nitrogen source for preparing the nitride is derived from urea, and ammonia gas with strong corrosivity is not used as a nitriding atmosphere, so that the method is green and environment-friendly;

3) the invention directly puts the sol precursor at high temperature for nitridation reaction, thereby avoiding the crystallization and solidification process and being beneficial to large-scale industrial production;

4) nitride oxide precursor NiMoO by traditional method₄The preparation process can directly adjust the initial charge ratio of the nickel element and the molybdenum element, so that the charge ratio is equal to the crystal structure element ratio, and the additional purification process is avoided;

5) preparation of Ni₂Mo₃When N nano-particle catalyst is used, a small amount of other metal salts, such as other metal chlorides, are directly mixed into the precursor to obtain doped Ni₂Mo₃An N nanoparticle catalyst;

6) the raw materials used in the method are all common industrial products which are easy to obtain.

Drawings

FIG. 1 shows Ni prepared in examples of the present invention₂Mo₃X-ray diffraction pattern of N nanoparticle catalyst.

FIG. 2 shows Ni prepared in an example of the present invention₂Mo₃An X-ray photoelectron spectrum of the Nnanoparticle catalyst Ni 2 p.

FIG. 3 shows Ni prepared in an example of the present invention₂Mo₃An X-ray photoelectron spectrum of the Nnanoparticle catalyst Mo 3 d.

FIG. 4 shows Ni prepared in examples of the present invention₂Mo₃Scanning electron microscopy of N nanoparticle catalyst.

FIG. 5 shows Ni prepared in an example of the present invention₂Mo₃N nanoparticle catalyst and commercial IrO₂Rotating disk electrode polarization plot (disk rotation speed 1600 rpm) versus Tafel plot for the/CB catalyst. In the figure, a and Ni₂Mo₃N；b、IrO₂/CB。

FIG. 6 shows Ni prepared in examples of the present invention₂Mo₃Stability test results of N nanoparticle catalysts. In the figure, a and Ni₂Mo₃N；b、IrO₂/CB。

Detailed Description

The present invention will be described in further detail with reference to the following examples, but the present invention is not limited to the following examples.

Examples

Preparing an electrocatalyst:

a. dissolving 3 mmol of anhydrous molybdenum chloride and 2 mmol of nickel chloride hexahydrate in 2 mL of ethanol solution to obtain clear and transparent solution;

b. adding 1 g of urea into the solution obtained in the step a, and standing for more than 12 hours at room temperature to obtain a sol precursor;

c. and c, placing the precursor obtained in the step b in a sealed tube furnace, calcining for 3 hours at the temperature of more than 800 ℃ in the argon atmosphere, and raising the temperature at the speed of 2 ℃/min. Naturally cooling to room temperature to obtain Ni₂Mo₃N nanoparticle catalysts. The X-ray diffraction result of the obtained product is shown in figure 1, the X-ray photoelectron spectroscopy is shown in figures 2 and 3, and the scanning electron microscopy is shown in figure 4;

electrochemical performance test

Weighing 5 mg of catalyst powder obtained by the method, dispersing the catalyst powder in 1 mL of isopropanol aqueous solution containing 0.05% of naphthol solution (the volume ratio of water to isopropanol is 1: 4), uniformly performing ultrasonic treatment, dripping 10 uL of catalyst powder on a pyrolytic graphite electrode (phi =5 mm) of a rotary disc device, completely volatilizing the dispersion liquid at room temperature, testing the performance of electrocatalytic oxygen evolution reaction by using the rotary disc electrode device, using a silver/silver chloride electrode as a reference electrode, using a platinum wire as a counter electrode, and using 0.1 mol/L of potassium hydroxide aqueous solution as electrolyte. Specifically, the polarization curve of the rotating disk electrode and the tafel plot are shown in fig. 5, and the stability test is shown in fig. 6.

Prepared Ni₂Mo₃The N nano-particle catalyst has higher catalytic activity, and the catalyst is 10 mA cm^-2The overpotential under the current density is 290 mV, and the Tafel slope is 68 mV dec^-1And has excellent stability.

The above are merely characteristic embodiments of the present invention, and do not limit the scope of the present invention in any way. All technical solutions formed by equivalent exchanges or equivalent substitutions fall within the protection scope of the present invention.

Claims (6)

Translated fromChinese

1.一种电催化剂材料，其特征在于：其催化活性成分为Ni₂Mo₃N、Ni₂Mo₃N复合材料中的一种或多种。1. An electrocatalyst material, characterized in that: its catalytically active component is one or more of Ni₂ Mo₃ N and Ni₂ Mo₃ N composite materials.2.根据权利要求1所述的电催化剂材料，其特征在于：所述Ni₂Mo₃N为立方相Ni₂Mo₃N。2 . The electrocatalyst material according to claim 1 , wherein the Ni₂ Mo₃ N is cubic phase Ni₂ Mo₃ N. 3 .3.根据权利要求2所述的电催化剂材料，其特征在于：所述立方相Ni₂Mo₃N的制备方法包括以下步骤：3. The electrocatalyst material according to claim 2, wherein the preparation method of the cubic phase Ni₂ Mo₃ N comprises the following steps:1）将氯化镍与氯化钼溶解于乙醇溶液中，得到澄清溶液；1) Dissolving nickel chloride and molybdenum chloride in ethanol solution to obtain a clear solution;2）在步骤1）中得到的澄清溶液中加入氮源，静置，得到胶状的前驱体；2) adding a nitrogen source to the clear solution obtained in step 1) and letting it stand to obtain a colloidal precursor;3）将步骤2）得到的前驱体在惰性气体中于500℃以上煅烧，即得到立方相Ni₂Mo₃N纳米颗粒。3) calcining the precursor obtained in step 2) at a temperature above 500° C. in an inert gas to obtain cubic Ni₂ Mo₃ N nanoparticles.4.根据权利要求3所述的电催化剂材料，其特征在于：所述乙醇溶液为无水乙醇，所述氮源为含氮有机物。4 . The electrocatalyst material according to claim 3 , wherein the ethanol solution is anhydrous ethanol, and the nitrogen source is a nitrogen-containing organic substance. 5 .5.根据权利要求4所述的电催化剂材料，其特征在于：所述含氮有机物为尿素，所述惰性气体为氮气或氩气。5 . The electrocatalyst material according to claim 4 , wherein the nitrogen-containing organic substance is urea, and the inert gas is nitrogen or argon. 6 .6.一种权利要求1-5中任一项所述的电催化剂材料的应用，其特征在于：包括电解水，金属-空气电池在内的所有包含析氧的电催化应用。6. An application of the electrocatalyst material according to any one of claims 1-5, characterized in that: all electrocatalytic applications including oxygen evolution including electrolysis of water and metal-air batteries.

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