阅读说明：本技术 一种二维Ni-Ir多孔纳米片及其制备方法与应用 (Two-dimensional Ni-Ir porous nanosheet and preparation method and application thereof ) 是由 唐亚文 刘启成 刘嘉琪 周心怡 徐林 孙冬梅 邱晓雨 于 2020-12-24 设计创作，主要内容包括：本发明公开了一种二维Ni-Ir多孔纳米片及其制备方法与应用,以镍氰化物、铱盐作为前驱体,经过油浴热制得二维层状结构的Hoffman型配合物前驱体,再经过高温煅烧氧化后,在特定的电化学窗口下还原得到一种二维Ni-Ir多孔纳米片。与传统制备方法相比,本发明方法工艺操作简单,用去离子水即可除去溶液中的杂离子,煅烧氧化过程不会释放温室气体,电化学还原过程干净环保无污染。本发明方法制备得到的二维Ni-Ir多孔纳米片纯度极高,具有比表面积大,活性位点多,电子传导性好,结构稳定等优点,对析氧展现出优异的电催化活性。(The invention discloses a two-dimensional Ni-Ir porous nanosheet and a preparation method and application thereof. Compared with the traditional preparation method, the method has simple process operation, can remove the impurity ions in the solution by using deionized water, does not release greenhouse gases in the calcining oxidation process, and has clean, environment-friendly and pollution-free electrochemical reduction process. The two-dimensional Ni-Ir porous nanosheet prepared by the method disclosed by the invention is extremely high in purity, has the advantages of large specific surface area, more active sites, good electronic conductivity, stable structure and the like, and shows excellent electrocatalytic activity on oxygen evolution.)

1. A two-dimensional Ni-Ir porous nanosheet is characterized in that a nickel cyanide and iridium salt are used as precursors, a Hoffman type complex precursor with a two-dimensional layered structure is prepared through oil bath heating, and is reduced under a specific electrochemical window after being calcined and oxidized at a high temperature to obtain the two-dimensional Ni-Ir porous nanosheet.

2. The preparation method of the two-dimensional Ni-Ir porous nanosheet based on claim 1, specifically comprising the following steps:

step 1, preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking nickel cyanide and iridium salt as precursors, carrying out oil bath heating at 70-90 ℃, reacting for 30-90 min, centrifuging the system after reaction, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

step 2, preparation of two-dimensional Ni-Ir porous nanosheet

And placing the dried Hoffman type complex precursor with the two-dimensional layered structure in a tubular furnace, heating to 250-340 ℃ by a program, calcining, oxidizing for 2-3 h, cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

3. The method for preparing two-dimensional Ni-Ir porous nanosheets according to claim 2, wherein step 1 is performedThe temperature rising rate of the temperature programming is 0.5-2 ℃ min^-1。

4. The method for preparing two-dimensional Ni-Ir porous nanosheet according to claim 2, wherein the concentration of nickel cyanide in step 1 is 0.03-0.10 mol L^-1Potassium nickel cyanide, the iridium salt is 0.03-0.10 mol L^-1Iridium chloride.

5. The preparation method of two-dimensional Ni-Ir porous nanosheet of claim 2, wherein the electrochemical window in step 2 has a voltage of 0-1.2V and a sweep rate of 0.03-0.08V-s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

6. The two-dimensional Ni-Ir porous nanosheet prepared based on the preparation method of claim 2.

7. Use of two-dimensional Ni-Ir porous nanoplates obtained according to claim 1, claim 2 or claim 6 in the preparation of catalysts for electrochemical oxygen evolution.

Technical Field

The invention relates to a two-dimensional Ni-Ir porous nanosheet and a preparation method and application thereof, and belongs to the technical field of Ni-Ir porous plate nanoflowers.

Background

Environmental pollution and energy crisis are becoming more serious, and the significant advantages of high energy efficiency and low emission of fuel cell technology are receiving wide attention. At present, hydrogen is mainly separated from fossil fuels such as natural gas, coal bed gas and the like, so that high-purity hydrogen is difficult to obtain, and the large-scale application of hydrogen energy is greatly limited. The water splitting reaction, consisting of hydrogen evolution, which is an attractive energy carrier to produce clean electricity in fuel cells, and oxygen evolution half-reactions, which are the rate-determining step in the electrolysis of water, as a sustainable hydrogen source, has a large overpotential that severely impedes large-scale commercial applications. The key to achieving this assumption is the development of improved electrocatalysts with appropriate efficiency and selectivity for the chemical conversions involved.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a two-dimensional Ni-Ir porous nanosheet and a preparation method and application thereof, the preparation process is simple and easy to implement, the reproducibility is good, and the obtained two-dimensional Ni-Ir porous nanosheet is regular in morphology and has the advantages of large specific surface area, many active sites, high electronic conductivity and the like.

In order to solve the problems of the prior art, the invention adopts the technical scheme that:

a two-dimensional Ni-Ir porous nanosheet is prepared by taking nickel cyanide and iridium salt as precursors, preparing a Hoffman type complex precursor with a two-dimensional layered structure through oil bath heating, calcining at high temperature, oxidizing, and reducing under a specific electrochemical window.

The preparation method of the two-dimensional Ni-Ir porous nanosheet specifically comprises the following steps:

step 1, preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking nickel cyanide and iridium salt as precursors, carrying out oil bath heating at 70-90 ℃, reacting for 30-90 min, centrifuging the system after reaction, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

step 2, preparation of two-dimensional Ni-Ir porous nanosheet

And placing the dried Hoffman type complex precursor with the two-dimensional layered structure in a tubular furnace, heating to 250-340 ℃ by a program, calcining, oxidizing for 2-3 h, cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

As an improvement, the temperature rising rate of the temperature programming in the step 1 is 0.5-2 ℃ min^-1。

The improvement is that the concentration of the nickel cyanide in the step 1 is 0.03-0.10 mol L^-1Potassium nickel cyanide, the iridium salt is 0.03-0.10 mol L^-1Iridium chloride.

As a modification, the voltage of the electrochemical window in the step 2 is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄. Here, 0V indicates initial (low) potential, and 1.2V indicates high potential.

The two-dimensional Ni-Ir porous nanosheet is obtained based on the preparation method.

The two-dimensional Ni-Ir porous nanosheet is applied to preparation of an electrochemical oxygen evolution catalyst.

Has the advantages that:

the invention relates to a two-dimensional Ni-Ir porous nanosheet and a preparation method and application thereof, wherein the method takes nickel cyanide and iridium salt as precursors, prepares a Hoffman type complex precursor with a two-dimensional layered structure through oil bath heating, and reduces the precursor through high-temperature calcination and oxidation under a specific electrochemical window to obtain a two-dimensional Ni-Ir porous nanosheet catalyst, and has the following advantages:

after electrochemical reductionThe porous structure and a large number of lattice defects can provide more catalytic sites, which is beneficial to the transmission and diffusion of electrolyte, thereby effectively improving the electrocatalytic activity;

currently, the commercial iridium dioxide has an Ir content of 85%, an actual measured value of the electrocatalytic oxygen evolution overpotential under alkaline conditions is 370 mV, and a theoretical calculated value of the iridium dioxide overpotential is 560 mV (Journal of electrochemical Chemistry, 607, 2007, 83), whereas in the present invention the noble metal loading is much lower than this, and the electrocatalytic oxygen evolution overpotential under alkaline conditions is only 326 mV, which is better than the commercial iridium dioxide; the load capacity of Ir is greatly reduced, and the cost is effectively reduced;

the two-dimensional Hoffman lamellar structure ensures that the catalyst is not easy to aggregate and dissolve in the catalysis process, thereby having better electrochemical stability.

Compared with the traditional preparation method, the method has the advantages that the process operation is simple, the synthesis is easy, the deionized water is used for removing the impurity ions in the solution, the greenhouse gas is not released in the calcining oxidation process, and the electrochemical reduction process is clean, environment-friendly and pollution-free. The two-dimensional Ni-Ir porous nanosheet prepared by the method disclosed by the invention is extremely high in purity, has the advantages of large specific surface area, more active sites, good electronic conductivity, stable structure and the like, and shows excellent electrocatalytic activity on oxygen evolution.

Drawings

FIG. 1 is a TEM spectrum of a Hoffman-type complex of a two-dimensional layered structure prepared in example 12;

FIG. 2 is an SEM image of a Hoffman-type complex of a two-dimensional layered structure prepared in example 12;

FIG. 3 is a TEM spectrum of a two-dimensional Ni-Ir porous nanosheet prepared in example 12;

FIG. 4 is an HRTEM spectrum of a two-dimensional Ni-Ir porous nanosheet prepared in example 12;

FIG. 5 is an XRD pattern of a Hoffman-type complex of two-dimensional layered structure prepared in example 12;

FIG. 6 is an XRD spectrum of the two-dimensional Ni-Ir porous nanosheet prepared in example 12;

FIG. 7 is the electrochemical oxygen evolution performance of the two-dimensional Ni-Ir porous nanosheet prepared in example 12;

FIG. 8 is the electrochemical oxygen evolution stability of the two-dimensional Ni-Ir porous nanosheets prepared in example 12;

FIG. 9 is an EDS spectrum of two-dimensional Ni-Ir porous nanoplates prepared in example 12.

Detailed description of the preferred embodiments

The technical solutions of the present invention are further described in detail by the following specific examples, but it should be noted that the following examples are only used for describing the content of the present invention and should not be construed as limiting the scope of the present invention.

A two-dimensional Ni-Ir porous nanosheet is prepared by taking nickel cyanide and iridium salt as precursors, preparing a Hoffman type complex precursor with a two-dimensional layered structure through oil bath heating, calcining at high temperature, oxidizing, and reducing under a specific electrochemical window.

The method specifically comprises the following steps:

step 1, preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking nickel cyanide and iridium salt as precursors, carrying out oil bath heating at 70-90 ℃, reacting for 30-90 min, centrifuging a reaction system, and washing the solid for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

step 2, preparation of two-dimensional Ni-Ir porous nanosheet

And placing the dried Hoffman type complex precursor with the two-dimensional layered structure in a tubular furnace, heating to 250-340 ℃ by a program, calcining, oxidizing for 2-3 h, cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the temperature rise rate of the temperature programming in the step 1 is 0.5-2 ℃ min^-1(ii) a The concentration of the nickel cyanide is 0.03-0.10 mol.L^-1Potassium nickel cyanide, said iridium saltThe concentration is 0.03-0.10 mol.L^-1Iridium chloride; in the step 2, the voltage of the electrochemical window is 0-1.2V, and the sweeping speed is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄. Here, 0V indicates initial (low) potential, and 1.2V indicates high potential.

In the preparation, the sweeping speed is fast and slow, the perchloric acid concentration is changed, and the preparation of the porous nanosheet is not influenced, so that the emphasis is not given in the following examples.

Example 1

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 70 ℃, keeping the reaction at the temperature for 30 min, centrifuging the reaction system, and washing the solid with water for 3 times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2 hours at the temperature of 250 ℃ by program heating; and after cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 2

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 80 ℃, keeping the reaction at the temperature for 30 min, centrifuging the reaction system, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2 hours at the temperature of 250 ℃ by program heating; and after cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08V s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 3

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 90 ℃, keeping the precursors reacted for 30 min at the temperature, centrifuging the reaction system, and washing the solid for several times with water to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2 hours at the temperature of 250 ℃ by program heating; and after cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 4

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 70 ℃, keeping the reaction at the temperature for 40min, centrifuging the reaction system, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2 hours at the temperature of 300 ℃ by program heating; and when the temperature is cooled to room temperature, loading the obtained material on carbon cloth, and reducing the material under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 5

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 80 ℃, keeping the reaction at the temperature for 40min, centrifuging the reaction system, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2 hours at the temperature of 300 ℃ by program heating; and after cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 6

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 90 ℃, keeping the precursors reacted for 40min at the temperature, centrifuging the reaction system, and washing the solid for several times with water to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2 hours at the temperature of 300 ℃ by program heating; and after cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 7

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 70 ℃, keeping the reaction at the temperature for 50min, centrifuging the reaction system, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

And placing the dried Hoffman type complex precursor with the two-dimensional layered structure in a tubular furnace, heating to 310 ℃ by a program, calcining, oxidizing for 2h, cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 8

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 80 ℃, keeping the reaction at the temperature for 50min, centrifuging the reaction system, and washing the solid for several times to obtain the Hoffman type complex precursor with the two-dimensional layered structure.

2) Preparation of two-dimensional Ni-Ir porous nanosheet

And placing the dried Hoffman type complex precursor with the two-dimensional layered structure in a tubular furnace, heating to 310 ℃ by a program, calcining, oxidizing for 2h, cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 9

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 90 ℃, keeping the temperature for reaction for 50min, centrifuging the reaction system, and washing the solid for several times to obtain the Hoffman type complex precursor with the two-dimensional layered structure.

2) Preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure in a tubular furnace, and calcining and oxidizing for 3 hours at the temperature of 315 ℃ by program heating; and after cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 10

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 70 ℃, keeping the precursors reacted for 60min at the temperature, centrifuging the reaction system, and washing the solid for several times with water to obtain the Hoffman type complex precursor with the two-dimensional layered structure.

2) Preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 3 hours at the temperature of 330 ℃ by program heating; and after cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 11

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 80 ℃, keeping the reaction at the temperature for 60min, centrifuging the reaction system, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

And placing the dried Hoffman type complex precursor with the two-dimensional layered structure in a tubular furnace, heating to 330 ℃ by a program, calcining, oxidizing for 3 h, cooling to room temperature, loading the obtained material on carbon cloth, and reducing under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 12

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 90 ℃, keeping the precursors reacted for 60min at the temperature, centrifuging the reaction system, and washing the solid for several times with water to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 3 hours at the temperature of 340 ℃ by program heating; and when the temperature is cooled to room temperature, loading the obtained material on carbon cloth, and reducing the material under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 13

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 90 ℃, keeping the precursors reacted for 70min at the temperature, centrifuging the reaction system, and washing the solid for several times with water to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 3 hours at the temperature of 340 ℃ by program heating; and when the temperature is cooled to room temperature, loading the obtained material on carbon cloth, and reducing the material under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 14

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 80 ℃, keeping the reaction at the temperature for 80min, centrifuging the reaction system, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 3 hours at the temperature of 340 ℃ by program heating; and when the temperature is cooled to room temperature, loading the obtained material on carbon cloth, and reducing the material under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 15

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating in an oil bath at 70 ℃, keeping the reaction at the temperature for 80min, centrifuging the reaction system, and washing the solid with water for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparation of two-dimensional Ni-Ir porous nanosheet

Placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2.5h by raising the temperature to 340 ℃ by a program; and when the temperature is cooled to room temperature, loading the obtained material on carbon cloth, and reducing the material under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

Example 16

A preparation method of a two-dimensional Ni-Ir porous nanosheet comprises the following steps:

1) preparation of Hoffman type complex precursor with two-dimensional layered structure

Taking potassium nickel cyanide and iridium chloride as precursors, heating the precursors in an oil bath at 90 ℃, keeping the temperature for reaction for 90min, centrifuging the reaction system, and washing the solid for several times to obtain a Hoffman type complex precursor with a two-dimensional layered structure;

2) preparing a two-dimensional Ni-Ir porous nanosheet: placing the dried Hoffman type complex precursor with the two-dimensional layered structure into a tubular furnace, and calcining and oxidizing for 2.5h by raising the temperature to 340 ℃ by a program; and when the temperature is cooled to room temperature, loading the obtained material on carbon cloth, and reducing the material under a specific electrochemical window to obtain the two-dimensional Ni-Ir porous nanosheet.

Wherein the voltage of the specific electrochemical window is 0-1.2V, and the sweep rate is 0.03-0.08 V.s^-1The electrolyte of the electrochemical window is 0.1-1M HClO₄。

And physically characterizing the two-dimensional Ni-Ir porous nanosheet prepared in example 12 by means of TEM, HRTEM, XRD, EDS and the like. As can be seen from the TEM (figure 1) picture, the catalyst precursor prepared by the method is a Hoffman type complex with a two-dimensional layered structure, and as can be seen from the SEM (figure 2), the Hoffman type complex with the two-dimensional layered structure presents a flower-like shape of sheet assembly. From TEM (fig. 3) and HRTEM (fig. 4), it can be seen that the surface of the electrochemical oxygen evolution catalyst two-dimensional Ni-Ir porous nanosheet is a porous structure, and a larger specific surface area and more active sites can be provided due to the porous structure of the electrochemical reduction zone. FIG. 5 is an XRD pattern of a precursor of a Hoffman type complex with a two-dimensional layered structure, all diffraction peaks of which are matched with Hoffman type coordination polymer Ir (H) with a two-dimensional layered structure₂O)₂[Ni(CN)₄]∙xH₂And (4) performing O anastomosis. FIG. 6 is an XRD (X-ray diffraction) diagram of a two-dimensional Ni-Ir porous nanosheet after electrochemical reduction, and compared with a standard card, the substance component NiO-Ir can be obtained. LSV polarization curve (FIG. 7) and 10 mA cm by two-dimensional Ni-Ir porous nanoplates^-2The CP curve (figure 8) of the voltage shows that the two-dimensional Ni-Ir porous nano-sheet is alkalineUnder the condition, the electrochemical oxygen evolution performance is superior to that of IrO₂And still exhibit stable excellent performance under long-term operation. FIG. 9 is an EDS spectrum of a two-dimensional Ni-Ir porous nanosheet, illustrating that the Ir content in the sample composition is extremely low.

The above description is only a preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, and any simple modifications or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the technical scope of the present invention are within the scope of the present invention.