阅读说明：本技术 一种硼掺杂硒化物异质结纳米材料的制备方法 (Preparation method of boron-doped selenide heterojunction nano material ) 是由 郑金龙 吴凯利 吕超杰 于 2021-06-08 设计创作，主要内容包括：本发明提供了一种硼掺杂硒化物异质结纳米材料的制备方法,属于电催化材料的制备方法技术领域。本发明中所合成的纳米材料由Ni-(0.85)Se和NiSe-2两种成分组成,并且表现出异质结结构,在该纳米材料中还引入了硼元素,这都有利于调控该材料的电子结构,加速电子的转移能力。该电解水催化剂不仅具有良好的电解水性能,而且还可应用于工农业污染物中尿素的降解,是一种环境友好型电解水催化剂,该纳米材料制备过程简单、稳定性好、易于实现工业化量产,是一种很有潜力的电解水催化剂,有望促进电解水制氢和污染物尿素降解产业化发展。(The invention provides a preparation method of a boron-doped selenide heterojunction nano material, belonging to the technical field of preparation methods of electrocatalytic materials. The nano material synthesized by the invention is made of Ni 0.85 Se and NiSe 2 The nanometer material is composed of two components, shows a heterojunction structure, and is also introduced with boron, which is beneficial to regulating and controlling the electronic structure of the material and accelerating the transfer capability of electrons. The electrolyzed water catalyst not only has good electrolyzed water performance, but also can be applied to the degradation of urea in industrial and agricultural pollutants, and is environment-friendly electrolyzed waterThe catalyst is simple in preparation process, good in stability and easy to realize industrial mass production, is a potential water electrolysis catalyst, and is expected to promote the industrial development of hydrogen production by water electrolysis and urea degradation of pollutants.)

1. A preparation method of a boron-doped selenide heterojunction nano material is characterized by comprising the following steps:

step one, weighing selenium powder and nickel acetate tetrahydrate, and dispersing the selenium powder and the nickel acetate tetrahydrate in a certain volume for deionizationAdding a certain amount of hydrazine hydrate solution dropwise after ultrasonic stirring treatment in water, stirring for a period of time, transferring the mixed solution into a reaction kettle, reacting in an oven at constant temperature for a period of time, naturally cooling and cooling, centrifugally washing the obtained product for multiple times by using deionized water and absolute ethyl alcohol, then transferring into the oven, and drying at a certain temperature to obtain NiSe₂A nanomaterial;

step two, weighing a certain amount of NiSe prepared₂Dispersing the nano material in absolute ethyl alcohol with a certain volume, adding a certain amount of sodium borohydride after ultrasonic stirring treatment, continuously stirring for a period of time, transferring the mixed solution into a reaction kettle, reacting in an oven at constant temperature for a period of time, naturally cooling, washing the obtained product by using deionized water and absolute ethyl alcohol for multiple times in a centrifugal manner, transferring the product into the oven, and drying at a certain temperature to obtain the boron-doped Ni_0.85Se/NiSe₂A heterojunction nanomaterial.

2. The method for preparing a boron-doped selenide heterojunction nanomaterial as claimed in claim 1, wherein: in the first step, the dosage of the selenium powder is 0.474-0.632 g, the dosage of the nickel acetate tetrahydrate is 0.374-0.498 g, and the volume of deionized water for dispersing the selenium powder and the nickel acetate tetrahydrate is as follows: 8-15 mL of hydrazine hydrate, wherein the mass fraction of the hydrazine hydrate is 50% -80%, and the dosage of the hydrazine hydrate is 20-35 mL.

3. The method for preparing a boron-doped selenide heterojunction nanomaterial as claimed in claim 1, wherein: in the first step, the reaction temperature is 140-160 ℃ at constant temperature in an oven, and the reaction time is 15-20 h at constant temperature in the oven.

4. The method for preparing a boron-doped selenide heterojunction nanomaterial as claimed in claim 1, wherein: in the first step, after dropwise adding a certain amount of hydrazine hydrate solution, stirring time is as follows: 0.5-1.0 h, and the drying temperature in the oven is as follows: and (2) drying in an oven at the temperature of 60-80 ℃ for the following time: 12-24 h.

5. The method for preparing a boron-doped selenide heterojunction nanomaterial as claimed in claim 1, wherein: in the second step, the NiSe₂The dosage of the nano material is 0.05-0.2 g, the dosage of the absolute ethyl alcohol is 15-30 mL, and the dosage of the sodium borohydride is as follows: 0.2 to 0.5 g.

6. The method for preparing a boron-doped selenide heterojunction nanomaterial as claimed in claim 1, wherein: in the second step, the constant temperature reaction temperature in the oven is 160-180 ℃, and the constant temperature reaction time in the oven is 1-4 h.

7. The method for preparing a boron-doped selenide heterojunction nanomaterial as claimed in claim 1, wherein: in the second step, the stirring time after the sodium borohydride is added is 0.2-0.5 h, and the drying temperature in the oven is as follows: and drying in an oven at 50-60 ℃ for the following time: 8-12 h.

Technical Field

The invention relates to a preparation method and application of a boron-doped selenide heterojunction nano material, belonging to the field of preparation of environment-friendly electrolytic water materials.

Background

With the development of economy, energy problems and environmental pollution problems become more and more serious. Hydrogen, as a clean, efficient, renewable energy source, is considered to be a desirable alternative to non-renewable fossil fuels. The water electrolysis hydrogen production industry can produce high-purity hydrogen, and is an important way for developing sustainable energy. The water electrolysis comprises two half reactions of hydrogen production (HER) and oxygen production (OER), but the hydrogen production by driving the water electrolysis is often large in energy consumption and low in efficiency due to kinetic obstruction, so that a water electrolysis catalyst needs to be developed to reduce energy consumption and improve energy conversion rate. Pt is considered to be a better HER catalyst, but Pt is expensive, and the activity and the stability of Pt in an alkaline solution are poor, so that the wide application of Pt is severely limited; RuO₂It is considered to be a good OER catalyst, however, its performance decay is severe, and OER is a four-electron process, the kinetics is slow, the overpotential is high, so that the actual voltage of electrolyzed water is far higher than its theoretical value (1.23V), and thus the high energy consumption limits its wide application.

NiSe₂Has become a common high-efficiency water electrolysis catalyst, and in order to further improve the catalytic performance, NiSe is used₂In situ grow Ni on the outer surface_0.85Se nano material, forming Ni_0.85Se/NiSe₂The heterojunction nano material is provided with an electronic structure which is beneficial to regulating and controlling the nano material and has the capability of accelerating electron transfer; at the same time, also to Ni_0.85Se/NiSe₂The heterojunction nano material is doped with boron, which is beneficial to improving the electrolytic water performance of the nano material.

The material not only shows excellent catalytic performance in electrolyzed water, but also can be used for degrading urea in industrial and agricultural pollutants, thereby achieving the aim of environmental friendliness. Researches find that in the water electrolysis reaction, the pollutant urea is added into the electrolyte, which is beneficial to reducing the overpotential of the reaction and can achieve the purpose of degrading pollutants at the same time, thereby achieving two purposes.

Disclosure of Invention

The invention provides a preparation method of a boron-doped selenide heterojunction nano material, which can be used as a high-efficiency electrolytic water catalyst and can also be used for catalytic degradation of pollutant urea.

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

(1)NiSe₂preparing a nano material: weighing selenium powder and nickel acetate tetrahydrate, dispersing the selenium powder and the nickel acetate tetrahydrate in deionized water with a certain volume, carrying out ultrasonic stirring treatment, dropwise adding a certain amount of hydrazine hydrate solution, stirring for a period of time, transferring the mixed solution into a reaction kettle, carrying out constant-temperature reaction in an oven for a period of time, naturally cooling, carrying out multiple centrifugal washing on the obtained product by using deionized water and absolute ethyl alcohol, then transferring the product into an oven, and drying at a certain temperature to obtain NiSe₂Nano material for standby.

(2) Boron doped Ni_0.85Se/NiSe₂Preparing a heterojunction nano material: weighing a certain amount of NiSe₂Dispersing the nano material in absolute ethyl alcohol with a certain volume, adding a certain amount of sodium borohydride after ultrasonic stirring treatment, continuously stirring for a period of time, transferring the mixed solution into a reaction kettle, reacting in an oven at constant temperature for a period of time, naturally cooling, washing the obtained product by using deionized water and absolute ethyl alcohol for multiple times in a centrifugal manner, transferring the product into the oven, drying at a certain temperature, and finally obtaining the boron-doped Ni_0.85Se/NiSe₂A heterojunction nanomaterial.

Preferably, in the step (1), the dosage of the selenium powder is 0.474-0.632 g, the dosage of the nickel acetate tetrahydrate is 0.374-0.498 g, the mass fraction of the hydrazine hydrate is 50% -80%, and the dosage of the hydrazine hydrate is 20-35 mL. .

Preferably, in the step (1), the reaction temperature is kept constant in an oven at 140-160 ℃, and the reaction time is kept constant in the oven for 15-20 hours.

Preferably, in the step (1), the stirring time after dropwise adding of a certain amount of hydrazine hydrate solution is as follows: 0.5-1.0 h, and the drying temperature in the oven is as follows: and (2) drying in an oven at the temperature of 60-80 ℃ for the following time: 12-24 h.

Preferably, in the step (2), NiSe is added₂The dosage of the nano material is 0.05-0.2 g, the dosage of the absolute ethyl alcohol is 15-30 mL, and boronThe amount of sodium hydride used was: 0.2 to 0.5 g.

Preferably, in the step (2), the reaction temperature is 160-180 ℃ at constant temperature in the oven, and the reaction time is 1-4 h at constant temperature in the oven.

Preferably, in the step (2), the stirring time after the sodium borohydride is added is 0.2-0.5 h, and the drying temperature in the oven is as follows: and drying in an oven at 50-60 ℃ for the following time: 8-12 h.

The invention has the advantages and beneficial effects that:

1. the invention provides a preparation method of a boron-doped selenide heterojunction nano material, wherein Ni in the nano material_0.85Se/NiSe₂The design of the heterojunction structure is beneficial to regulating and controlling the electronic structure of the nano material and accelerating the electron transfer capacity; the doping of the boron element is also beneficial to optimizing the electronic structure of the nano material, accelerating the electron transfer capability and improving the catalytic performance of the nano material.

2. The invention provides a preparation method of a boron-doped selenide heterojunction nano material, and the water electrolysis catalyst has good catalytic performance, simple preparation process, high stability and low price of raw materials, is easy to realize industrial mass production, and can contribute to the realization of the industrial development of hydrogen production by water electrolysis.

3. The invention provides a preparation method of a boron-doped selenide heterojunction nano material, wherein in the water electrolysis reaction, a pollutant urea is added into an electrolyte, so that the overpotential of the reaction is reduced, and the purpose of degrading pollutants can be achieved.

Drawings

FIG. 1: the invention provides a flow chart of a preparation method of a boron-doped selenide heterojunction nano material;

FIG. 2: NiSe obtained in example 1 of the invention₂Nanomaterial and boron-doped Ni obtained in examples 1, 2, 3 and 4_0.85Se/NiSe₂An X-ray powder diffraction pattern of the heterojunction nanomaterial;

FIG. 3: boron-doped Ni obtained in examples 1, 2, 3 and 4 of the present invention_0.85Se/NiSe₂Scanning of heterojunction nanomaterialsAn electron microscope image;

FIG. 4: NiSe obtained in example 1 of the invention₂Nanomaterial and boron-doped Ni obtained in examples 1, 2, 3 and 4_0.85Se/NiSe₂A hydrogen evolution reaction performance diagram of the heterojunction nano material;

FIG. 5: NiSe obtained in example 1 of the invention₂Nanomaterial and boron-doped Ni obtained in examples 1, 2, 3 and 4_0.85Se/NiSe₂An oxygen evolution reaction performance diagram of the heterojunction nano material;

FIG. 6: boron-doped Ni obtained in example 2 of the invention_0.85Se/NiSe₂The water electrolysis performance and the pollutant degradation urea performance of the heterojunction nano material are shown.

Detailed Description

The present invention will be described in detail below with reference to the drawings and examples, but the scope of the present invention is not limited to the following examples.

Example 1:

(1)NiSe₂preparing a nano material: weighing 0.632g of selenium powder and 0.498g of nickel acetate tetrahydrate, dispersing the selenium powder and the nickel acetate tetrahydrate in 15mL of deionized water, carrying out ultrasonic stirring treatment, dropwise adding 30mL of hydrazine hydrate solution with the mass fraction of 80%, stirring for 1 hour, transferring the mixed solution into a reaction kettle, reacting in an oven at 140 ℃ for 20 hours, naturally cooling, carrying out multiple centrifugal washing on the obtained product with deionized water and absolute ethyl alcohol, transferring into the oven, and drying at 70 ℃ for 24 hours to obtain NiSe₂Nano material for standby.

(2) Boron doped Ni_0.85Se/NiSe₂Preparing a heterojunction nano material: 0.1g of NiSe prepared is weighed₂Dispersing the nano material in 20mL of absolute ethyl alcohol, performing ultrasonic stirring treatment, adding 0.3g of sodium borohydride, continuously stirring for 0.5 hour, transferring the mixed solution into a reaction kettle, reacting in an oven at 160 ℃ for 1 hour, naturally cooling, performing centrifugal washing on the obtained product for multiple times by using deionized water and absolute ethyl alcohol, transferring the product into an oven, drying at 50 ℃ for 12 hours, and finally obtaining the boron-doped Ni_0.85Se/NiSe₂A heterojunction nanomaterial.

Example 2:

(1)NiSe₂preparing a nano material: weighing 0.632g of selenium powder and 0.498g of nickel acetate tetrahydrate, dispersing the selenium powder and the nickel acetate tetrahydrate in 15mL of deionized water, carrying out ultrasonic stirring treatment, dropwise adding 30mL of hydrazine hydrate solution with the mass fraction of 80%, stirring for 1 hour, transferring the mixed solution into a reaction kettle, reacting in an oven at 140 ℃ for 20 hours, naturally cooling, carrying out multiple centrifugal washing on the obtained product with deionized water and absolute ethyl alcohol, transferring into the oven, and drying at 70 ℃ for 24 hours to obtain NiSe₂Nano material for standby.

(2) Boron doped Ni_0.85Se/NiSe₂Preparing a heterojunction nano material: 0.1g of NiSe prepared is weighed₂Dispersing the nano material in 20mL of absolute ethyl alcohol, performing ultrasonic stirring treatment, adding 0.3g of sodium borohydride, continuously stirring for 0.5 hour, transferring the mixed solution into a reaction kettle, reacting in an oven at 160 ℃ for 2 hours, naturally cooling, washing the obtained product by using deionized water and absolute ethyl alcohol for multiple times of centrifugation, transferring into an oven, drying at 50 ℃ for 12 hours, and finally obtaining the boron-doped Ni_0.85Se/NiSe₂A heterojunction nanomaterial.

Example 3:

(1)NiSe₂preparing a nano material: weighing 0.632g of selenium powder and 0.498g of nickel acetate tetrahydrate, dispersing the selenium powder and the nickel acetate tetrahydrate in 15mL of deionized water, carrying out ultrasonic stirring treatment, dropwise adding 30mL of hydrazine hydrate solution with the mass fraction of 80%, stirring for 1 hour, transferring the mixed solution into a reaction kettle, reacting in an oven at 140 ℃ for 20 hours, naturally cooling, carrying out multiple centrifugal washing on the obtained product with deionized water and absolute ethyl alcohol, transferring into the oven, and drying at 70 ℃ for 24 hours to obtain NiSe₂Nano material for standby.

(2) Boron doped Ni_0.85Se/NiSe₂Preparing a heterojunction nano material: 0.1g of NiSe prepared is weighed₂Dispersing the nano material in 20mL of absolute ethyl alcohol, carrying out ultrasonic stirring treatment, adding 0.3g of sodium borohydride, continuously stirring for 0.5 hour, transferring the mixed solution into a reaction kettle, and reacting for 3 hours at 160 ℃ in an ovenNaturally cooling, centrifugally washing the obtained product with deionized water and absolute ethyl alcohol for multiple times, transferring the product into a drying oven, and drying the product for 12 hours at 50 ℃ to finally obtain the boron-doped Ni_0.85Se/NiSe₂A heterojunction nanomaterial.

Example 4:

(1)NiSe₂preparing a nano material: weighing 0.632g of selenium powder and 0.498g of nickel acetate tetrahydrate, dispersing the selenium powder and the nickel acetate tetrahydrate in 15mL of deionized water, carrying out ultrasonic stirring treatment, dropwise adding 30mL of hydrazine hydrate solution with the mass fraction of 80%, stirring for 1 hour, transferring the mixed solution into a reaction kettle, reacting in an oven at 140 ℃ for 20 hours, naturally cooling, carrying out multiple centrifugal washing on the obtained product with deionized water and absolute ethyl alcohol, transferring into the oven, and drying at 70 ℃ for 24 hours to obtain NiSe₂Nano material for standby.

(2) Boron doped Ni_0.85Se/NiSe₂Preparing a heterojunction nano material: 0.1g of NiSe prepared is weighed₂Dispersing the nano material in 20mL of absolute ethyl alcohol, performing ultrasonic stirring treatment, adding 0.3g of sodium borohydride, continuously stirring for 0.5 hour, transferring the mixed solution into a reaction kettle, reacting for 4 hours at 160 ℃ in an oven, naturally cooling, washing the obtained product by using deionized water and absolute ethyl alcohol for multiple times of centrifugation, transferring the product into the oven, drying for 12 hours at 50 ℃ to finally obtain the boron-doped Ni_0.85Se/NiSe₂A heterojunction nanomaterial.

Although the specific embodiments of the present invention have been described with reference to the examples, the scope of the present invention is not limited thereto, and those skilled in the art will appreciate that various modifications and variations can be made without inventive effort by those skilled in the art based on the technical solution of the present invention.