Rapid preparation method of iron-doped nickel selenide, and use of iron-doped nickel selenide in cathode for water electrolysis

Abstract

A rapid preparation method of iron-doped nickel selenide, and use of the iron-doped nickel selenide in a cathode for water electrolysis is detailed. The preparation method includes the following steps: (1) preparing a ferric acetate-containing premixed solution; (2) immersing a nickel mesh into the premixed solution for a period of time, taking out, and drying by heating to obtain a ferric acetate-attached nickel mesh; (3) placing the ferric acetate-attached nickel mesh in a heating zone of a tubular furnace, and placing a selenium powder on an edge of the heating zone of the tubular furnace; and (4) conducting selenization to obtain the iron-doped nickel selenide that is directly connected to a water electrolysis device as a cathode for water electrolysis. The cathode for water electrolysis can be directly applied to a water electrolysis device. Ferric nitrate may be used in replacement for ferric acetate in conjunction with water rather than N,N-dimethylformamide in the premixed solution of step 1.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of hydrogen production by water electrolysis, in particular to a preparation method of a photosensitive iron-doped nickel selenide cathode for water electrolysis. BACKGROUND

[0002] Hydrogen has an extremely high specific energy, and has a combustion product of water only, which is an ideal fuel capable of replacing fossil energy. More importantly, hydrogen can be produced through water electrolysis, forming a clean closed loop from the decomposition of water to produce hydrogen to the combustion of hydrogen into water. However, the current hydrogen production by water electrolysis has a high cost and is difficult to conduct large-scale commercial production. Therefore, it is necessary to develop the hydrogen production by water electrolysis to efficiently produce high-purity hydrogen to meet market demands and replace fossil fuels such as coal.

[0003] The cost of hydrogen production by water electrolysis includes two parts: the first one is power consumption required in the hydrogen production by water electrolysis; and the second one is a cost of hydrogen production by water electrolysis device, including the cost of a cathode for water electrolysis, the cost of an anode for water electrolysis, and the cost of an electrolyte. Iron-doped nickel selenide is a material with desirable electrocatalytic activity and also a semiconductor material. It is known that semiconductor materials have a photoelectric effect under suitable light illumination, thereby increasing a carrier concentration on the surface of semiconductor materials. Therefore, the cathode for water electrolysis based on iron-doped nickel selenide is excited by light illumination, and photo-generated carriers obtained by the photoelectric effect improve electrical properties on a surface of the cathode for water electrolysis, thereby reducing the external power supply required for water electrolysis. On the other hand, a rapidly-prepared nickel selenide cathode for water electrolysis can effectively reduce a production cost of the cathode for water electrolysis, thus further reducing the cost of the hydrogen production by water electrolysis device. SUMMARY

[0004] Aiming at the prior art, the present disclosure provides a preparation method of a photosensitive iron-doped nickel selenide cathode for water electrolysis, so as to reduce a cost of 02 10 23 a water electrolysis device and a power consumption during hydrogen production by water electrolysis.

[0005] To achieve the above objective, the technical solution adopted by the present disclosure is as follows: a preparation method of a photosensitive iron-doped nickel selenide cathode for water electrolysis is provided, including the following steps:

[0006] step 1: dissolving ferric acetate at a concentration of 0.2 g / mL into N,N-dimethylformamide to obtain a ferric acetate-containing premixed solution;

[0007] step 2: immersing a nickel mesh into the premixed solution obtained in step 1 for 1 sec to 2 sec, taking out with tweezers, and drying in an oven or a heating platform at 60°C for 5 min to 10 min to obtain a ferric acetate-attached nickel mesh;

[0008] step 3: placing the ferric acetate-attached nickel mesh obtained in step 2 in a heating zone of a tubular furnace, and placing a selenium powder on an edge of the heating zone of the tubular furnace; and

[0009] step 4: conducting selenization in the heating zone of the tubular furnace at 480°C to 495°C for 5 min to 6 min to obtain the iron-doped nickel selenide that is directly connected to a water electrolysis device as a cathode for water electrolysis.

[0010] Preferably, the nickel mesh is immersed in the premixed solution for 1 sec and then taken out.

[0011] Preferably, the ferric acetate-attached nickel mesh is placed on the heating zone of the tubular furnace, and the selenium powder is placed on the edge of the heating zone of the tubular furnace; and selenization is conducted in the heating zone of the tubular furnace at 495°C for 5 min.

[0012] The present disclosure further provides a photosensitive iron-doped nickel selenide cathode for water electrolysis prepared by the preparation method of iron-doped nickel selenide. The cathode for water electrolysis is used as a cathode of a water electrolysis device for hydrogen production, showing obvious performance advantages; through the effect of solar energy, the cathode for water electrolysis has improved water electrolysis efficiency compared with the traditional cathodes for electrolysis water.

[0013] Preferably, the iron-doped nickel selenide cathode for water electrolysis is applied to an water electrolysis device; the water electrolysis device includes a cathode for water electrolysis, a graphite paper-based counter electrode, a reference electrode, and an electrolyte; the reference electrode is a Hg / HgO reference electrode; and the electrolyte is a potassium hydroxide solution with a pH value of 14. Through the photosensitive and iron-doped nickel selenide cathode for water electrolysis, a hydrogen production performance by water electrolysis of the water electrolysis device under light illumination is improved, thereby reducing the operating cost of 02 10 23 the water electrolysis device.

[0014] The present disclosure has the beneficial effects as follows: in the present disclosure, the preparation method has simple conditions and a relatively short production time; by the preparation method of an iron-doped nickel selenide cathode for water electrolysis, a photosensitive iron-doped nickel selenide cathode for water electrolysis is obtained; the cathode for water electrolysis has a stable structure, a desirable catalytic activity, and a light sensitivity. When the iron-doped nickel selenide is used as the cathode for water electrolysis to produce hydrogen by water electrolysis, the iron-doped nickel selenide cathode for water electrolysis can be irradiated with sunlight to improve a hydrogen production efficiency, thereby reducing the electricity required for hydrogen production by water electrolysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 shows a scanning electron microscopy (SEM) image of a photosensitive iron-doped nickel selenide cathode for water electrolysis;

[0016] FIG. 2 shows an X-ray photoelectron energy spectrum of Fe on a surface of the photosensitive iron-doped nickel selenide cathode for water electrolysis; and

[0017] FIG. 3 shows a polarization curve of the photosensitive iron-doped nickel selenide cathode for water electrolysis. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The technical solutions of the embodiments of the present disclosure are clearly and completely described below with reference to the accompanying drawings. Apparently, the described embodiments are merely a part rather than all of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

[0019] The present disclosure proposes a preparation method of a photosensitive iron-doped nickel selenide cathode for water electrolysis, including the following steps:

[0020] step 1: dissolving ferric acetate at a concentration of 0.2 g / mL into N,N-dimethylformamide to obtain a ferric acetate-containing premixed solution;

[0021] step 2: immersing a nickel mesh into the premixed solution obtained in step 1 for 1 sec to 2 sec, taking out with tweezers, and drying in an oven or a heating platform at 60°C for 5 min to 10 min to obtain a ferric acetate-attached nickel mesh;

[0022] step 3: placing the ferric acetate-attached nickel mesh obtained in step 2 in a heating zone of a tubular furnace, and placing a selenium powder on an edge of the heating zone of the 02 10 23 tubular furnace; and

[0023] step 4: conducting selenization in the heating zone of the tubular furnace at 480°C to 495°C for 5 min to 6 min to obtain the iron-doped nickel selenide that is directly connected to a water electrolysis device as a cathode for water electrolysis. The SEM image of FIG. 1 shows that the iron-doped nickel selenide cathode for water electrolysis obtained by the preparation method has a stable wave structure, and the void structure of the nickel mesh still exists. This provides a huge specific surface area and a large number of active sites for the iron-doped nickel selenide cathode for water electrolysis.

[0024] Further, the nickel mesh is immersed in the premixed solution for 1 sec and then taken out.

[0025] Further, the ferric acetate-attached nickel mesh is placed on the heating zone of the tubular furnace, and the selenium powder is placed on the edge of the heating zone of the tubular furnace; and selenization is conducted in the heating zone of the tubular furnace at 495°C for 5 min. The X-ray photoelectron spectrum of the Fe element in FIG. 2 shows that the Fe element has been successfully doped into the nickel selenide lattice. Compared with the standard X-ray photoelectron spectrum of Fe element, it can be determined that the Fe element in the iron-doped nickel selenide cathode for water electrolysis is in a positive trivalent state.

[0026] Further, the present disclosure further provides a photosensitive iron-doped nickel selenide cathode for water electrolysis prepared by the preparation method of a photosensitive iron-doped nickel selenide cathode for water electrolysis.

[0027] Further, the present disclosure further provides use of the photosensitive iron-doped nickel selenide cathode for water electrolysis, where the iron-doped nickel selenide cathode for water electrolysis is applied to an water electrolysis device; the water electrolysis device includes a cathode for water electrolysis, a graphite paper-based counter electrode, a reference electrode, and an electrolyte; the reference electrode is a Hg / HgO reference electrode; and the electrolyte is a potassium hydroxide solution with a pH value of 14. The polarization curve in FIG. 3 shows that when the photosensitive iron-doped nickel selenide cathode for water electrolysis is applied with an overpotential of 150 mV, a current density generated on the electrode is 32.6 mA / cm2. After applying light illumination to the photosensitive iron-doped nickel selenide cathode for water electrolysis, the current density is increased to 42.1 mA / cm2 under the same overpotential of 150 mV, with an increase of 29.1%.

[0028] Within the scope of the claims, all modifications and variations made by those skilled in the art without creative efforts shall fall within the protection scope of the present disclosure.

Claims

02 10 231. A preparation method of iron-doped nickel selenide, comprising the following steps:step 1: dissolving ferric acetate at a concentration of 0.2 g / mL into N,N-dimethylformamide to obtain a ferric acetate-containing premixed solution;step 2: immersing a nickel mesh into the premixed solution obtained in step 1 for 1 sec to 2 sec, taking out with tweezers, and drying in an oven or a heating platform at 60°C for 5 min to 10 min to obtain a ferric acetate-attached nickel mesh;step 3: placing the ferric acetate-attached nickel mesh obtained in step 2 in a heating zone of a tubular furnace, and placing a selenium powder on an edge of the heating zone of the tubular furnace; andstep 4: conducting selenization in the heating zone of the tubular furnace at 480°C to 495°C for 5 min to 6 min to obtain the iron-doped nickel selenide that is directly connected to a water electrolysis device as a cathode for water electrolysis.

2. The preparation method of iron-doped nickel selenide according to claim 1, wherein the nickel mesh is immersed in the premixed solution for 1 sec and then taken out.

3. The preparation method of iron-doped nickel selenide according to claim 1, wherein the ferric acetate-attached nickel mesh is placed on the heating zone of the tubular furnace, and the selenium powder is placed on the edge of the heating zone of the tubular furnace; and selenization is conducted in the heating zone of the tubular furnace at 495°C for 5 min.

4. A photosensitive iron-doped nickel selenide cathode for water electrolysis prepared by the preparation method of iron-doped nickel selenide according to any one of claims 1 to 3.

5. Use of the iron-doped nickel selenide according to claim 4 in a cathode for water electrolysis, wherein the iron-doped nickel selenide cathode for water electrolysis is applied in a water electrolysis device; the water electrolysis device comprises a cathode for water electrolysis, a graphite paper-based counter electrode, areference electrode, and an electrolyte; the reference electrode is a Hg / HgO reference electrode; and the electrolyte is a potassium hydroxide solution with a pH value of 14.02 10 23

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