A method for producing a layered nickel oxyhydroxide

Abstract

The application provides a preparation method of layered hydroxyl nickel oxide, and the preparation method comprises the following steps: activating nickel powder to obtain activated nickel powder; placing the activated nickel powder in an alkali solution, heating to a reaction temperature under a protective atmosphere, and introducing an oxidizing gas to react; and after the reaction, performing solid-liquid separation to obtain the layered hydroxyl nickel oxide. The preparation method uses nickel powder as a raw material, and hydroxyl nickel oxide is prepared by one-step method, so that the process is short, the technology is simple, and the product conversion rate is high.

Description

Technical Field

[0001] This invention belongs to the field of materials preparation and relates to a method for preparing layered nickel hydroxyl oxide. Background Technology

[0002] Nickel hydroxyl oxide (NiOH) is an important transition metal hydroxide with many superior properties, thus attracting widespread attention in the fields of electrochemistry and energy storage. NiOH exhibits excellent electrochemical performance, including high specific capacitance, high conductivity, and good cycle stability. This makes NiOH an ideal material for batteries, supercapacitors, and other energy storage devices. Furthermore, NiOH can also serve as an electrocatalyst, showing particularly good performance in the oxygen evolution reaction (OER).

[0003] However, despite the excellent electrochemical performance of nickel hydroxyl oxide, research on its synthesis is limited. For example, some literature uses ozone as an oxidant to oxidize nickel hydroxide to nickel hydroxyl oxide, but this requires continuous ozone flow, which not only increases production costs but also poses safety risks due to the instability and toxicity of ozone. The method for preparing nickel hydroxyl oxide disclosed in CN 1187270C has a low conversion rate of only 40%-80%, and requires too much oxidant, resulting in resource waste and difficulties in subsequent oxidant separation. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a method for preparing layered nickel hydroxyl oxide. The method uses nickel powder as raw material and prepares nickel hydroxyl oxide in one step, which has a short process, simple technology, and high product conversion rate.

[0005] To achieve the above-mentioned technical effects, the present invention adopts the following technical solution:

[0006] This invention provides a method for preparing layered nickel hydroxyl oxide, the method comprising:

[0007] Nickel powder is activated to obtain activated nickel powder;

[0008] The activated nickel powder is placed in an alkaline solution, heated to the reaction temperature under a protective atmosphere, and then an oxidizing gas is introduced to carry out the reaction.

[0009] After the reaction, solid-liquid separation is performed to obtain the layered nickel hydroxy oxide.

[0010] As a preferred embodiment of the present invention, the activation method includes placing the nickel powder in an acidic solution to remove oxides from the surface of the nickel powder.

[0011] As a preferred embodiment of the present invention, the acidic solution includes hydrochloric acid with a concentration of 10-37 wt%, such as 10 wt%, 12 wt%, 15 wt%, 18 wt%, 20 wt%, 22 wt%, 25 wt%, 28 wt%, 30 wt%, 32 wt%, 35 wt%, or 37 wt%, etc., but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0012] Preferably, the activation time is 0.5 to 3 min, such as 0.5 min, 1 min, 1.5 min, 2 min, 2.5 min or 3 min, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0013] Preferably, the activated nickel powder is subjected to a first cleaning process after the activation treatment.

[0014] As a preferred embodiment of the present invention, the activated nickel powder is ultrasonically dispersed before being placed in an alkaline solution.

[0015] As a preferred embodiment of the present invention, the alkaline solution comprises an aqueous solution of sodium hydroxide and / or potassium hydroxide.

[0016] Preferably, the concentration of the alkaline solution is 60-80 wt%, such as 60 wt%, 62 wt%, 65 wt%, 68 wt%, 70 wt%, 72 wt%, 75 wt%, 78 wt%, or 80 wt%, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0017] As a preferred technical solution of the present invention, the heating rate is 5~10 ℃ / min, such as 5℃ / min, 6℃ / min, 7℃ / min, 8℃ / min, 9℃ / min or 10℃ / min, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0018] Preferably, the reaction temperature is 150~300℃, such as 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, 260℃, 270℃, 280℃, 290℃ or 300℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0019] As a preferred embodiment of the present invention, the oxidizing gas includes oxygen.

[0020] Preferably, the partial pressure of the oxidizing gas is 0.1~8 MPa, such as 0.1 MPa, 0.2 MPa, 0.5 MPa, 1 MPa, 1.5 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa or 8 MPa, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0021] As a preferred technical solution of the present invention, the reaction time is 4 to 48 hours, such as 4 hours, 8 hours, 12 hours, 16 hours, 20 hours, 24 hours, 28 hours, 32 hours, 36 hours, 40 hours, 44 hours or 48 hours, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0022] Preferably, the reaction is carried out under stirring at a speed of 200 to 600 rpm, such as 200 rpm, 300 rpm, 400 rpm, 500 rpm or 600 rpm, but not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0023] As a preferred technical solution of the present invention, the preparation method further includes washing the solid obtained after solid-liquid separation with water and acid in sequence.

[0024] As a preferred embodiment of the present invention, the method for preparing the layered nickel hydroxyl oxide includes:

[0025] The nickel powder is placed in an acidic solution to remove oxides from its surface. The acidic solution includes hydrochloric acid with a concentration of 10-37 wt%. The activation time is 0.5-3 min to obtain activated nickel powder.

[0026] The activated nickel powder is ultrasonically dispersed, and then placed in an alkaline solution with a concentration of 60-80 wt%. Under a protective atmosphere, the temperature is increased to a reaction temperature of 150-300 °C at a heating rate of 5-10 °C / min. Oxygen is introduced to carry out the reaction, with a partial pressure of 0.1-8 MPa. The reaction time is 4-48 h. The reaction is carried out under stirring at a stirring rate of 200-600 rpm.

[0027] After the reaction, solid-liquid separation is performed, and the solid obtained after solid-liquid separation is washed with water and acid in sequence to obtain the layered nickel hydroxy oxide.

[0028] Compared with the prior art, the present invention has at least the following beneficial effects:

[0029] (1) The present invention provides a method for preparing layered nickel hydroxyl oxide, wherein the preparation method is prepared by one-step oxidation of nickel powder, the process is simple and the preparation process is short;

[0030] (2) The present invention provides a method for preparing layered nickel hydroxyl oxide, wherein the preparation method uses oxygen as an oxidant, the reaction is clean, and there is no oxidant residue;

[0031] (3) The present invention provides a method for preparing layered nickel hydroxyl oxide, wherein the preparation method has a high reaction conversion rate of over 97% and the particle size of the product is easy to control. Attached Figure Description

[0032] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0033] The following detailed embodiments further illustrate the technical solution of this application.

[0034] This invention provides a method for preparing layered nickel hydroxyl oxide, the method comprising:

[0035] Nickel powder is activated to obtain activated nickel powder;

[0036] The activated nickel powder is placed in an alkaline solution, heated to the reaction temperature under a protective atmosphere, and then an oxidizing gas is introduced to carry out the reaction.

[0037] After the reaction, solid-liquid separation is performed to obtain the layered nickel hydroxy oxide.

[0038] In this invention, the reason why the preparation method can prepare layered nickel hydroxyl oxide with high conversion rate is due to the high concentration of OH... - In the presence of alkali, the activity coefficients of each component in the medium increase sharply with the increase of alkali concentration. The introduction of oxygen causes the formation of highly chemically active and highly ionicly active oxygen anions in the system, which allows nickel powder to react in one step to form nickel hydroxyl oxide with a high conversion rate.

[0039] In one specific embodiment of the present invention, the particle size of the nickel powder can be 50 nm to 100 μm, such as 50 nm, 100 nm, 200 nm, 500 nm, 1000 nm, 5 μm, 10 μm, 20 μm, 50 μm or 100 μm, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0040] In one specific embodiment of the present invention, the first cleaning treatment can be a water washing treatment. The temperature of the water washing treatment can be 5~40℃, the time can be 1~2min, and the water washing is repeated until the pH of the washing solution is greater than 5, and then the solution is dried.

[0041] The temperature of the water washing treatment can be 5℃, 10℃, 20℃, 30℃ or 40℃, etc., and the time can be 1min, 1.2min, 1.5min, 1.8min or 2min, etc., but it is not limited to the listed values. Other unlisted values ​​within the above ranges are also applicable.

[0042] In one specific embodiment of the present invention, the drying method may be vacuum freeze drying.

[0043] In one specific embodiment of the present invention, the ultrasonic dispersion frequency can be 20~30kHz, the ultrasonic power can be 500W, the temperature can be room temperature, the time can be 10~15min, and the number of repetitions can be 3.

[0044] The frequency of ultrasonic dispersion can be 20 kHz, 21 kHz, 22 kHz, 23 kHz, 24 kHz, 25 kHz, 26 kHz, 27 kHz, 28 kHz, 29 kHz or 30 kHz, etc., and the time can be 10 min, 11 min, 12 min, 13 min, 14 min or 15 min, etc., but it is not limited to the listed values. Other unlisted values ​​within the above ranges are also applicable.

[0045] In one specific embodiment of the present invention, the heating can be carried out under stirring, and the stirring rate can be 200~600 rpm, such as 200 rpm, 300 rpm, 400 rpm, 500 rpm or 600 rpm, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0046] In one specific embodiment of the present invention, the protective atmosphere can be any one of nitrogen, helium, neon, argon, krypton, xenon or radon.

[0047] In one specific embodiment of the present invention, the solid after solid-liquid separation is washed with water and acid to remove residual alkali. The water washing temperature can be 60~80℃ and the time can be 5~30min. The hydrochloric acid concentration used for acid washing is 0.1~3wt% and the time can be 3~30min.

[0048] The water temperature can be 60℃, 62℃, 65℃, 68℃, 70℃, 72℃, 75℃, 78℃, or 80℃, etc., and the time can be 5 min, 10 min, 15 min, 20 min, 25 min, or 30 min, etc. The concentration of hydrochloric acid used for pickling can be 0.1 wt%, 0.2 wt%, 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, or 3 wt%, etc., and the time can be 5 min, 10 min, 15 min, 20 min, 25 min, or 30 min, etc., but is not limited to the listed values. Other unlisted values ​​within the above ranges are also applicable.

[0049] In one specific embodiment of the present invention, after pickling, water washing is performed to remove residual acid until the pH of the washing solution is neutral.

[0050] In one specific embodiment of the present invention, the layered nickel hydroxy oxide is γ-NiOOH with a particle size of 0.1~120μm.

[0051] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0052] Example 1

[0053] This embodiment provides a γ-NiOOH material, and the preparation method of the γ-NiOOH material is as follows:

[0054] (1) Select nickel powder with a particle size of about 80 μm and a nickel content of more than 99.9%, activate it with a 10% hydrochloric acid solution for 0.5 min, and then wash it with water multiple times. The water washing process is washing with deionized water at 5°C for 1 min until the pH of the washing solution is greater than 5. Finally, freeze dry it under vacuum to obtain activated nickel powder.

[0055] (2) The activated nickel powder obtained in step (1) was ultrasonically dispersed at a frequency of 20 kHz, an ultrasonic power of 500 W, a temperature of room temperature, and a time of 10 min. This was repeated three times. Then, the powder was placed in a 60% sodium hydroxide solution and heated under nitrogen protection at a rate of 5 °C / min. During the heating process, the stirring rate was 200 rpm.

[0056] (3) After the temperature of the reaction system in step (2) is raised to 150°C, oxygen is introduced to react. The partial pressure of the introduced oxygen is 0.1 MPa, the reaction time is 4 h, the stirring rate during the reaction is 200 rpm, and solid-liquid separation is performed after the reaction is completed.

[0057] (4) The solid obtained in step (3) is first washed with water at a temperature of 60°C for 5 minutes. After washing, it is acid-washed with a 0.1% hydrochloric acid solution for 3 minutes. After acid washing, it is washed with deionized water multiple times until the pH of the washing solution is neutral. The temperature of the deionized water is room temperature. The final solid obtained is γ-NiOOH.

[0058] Example 2

[0059] This embodiment provides a γ-NiOOH material, and the preparation method of the γ-NiOOH material is as follows:

[0060] (1) Select nickel powder with a particle size of about 80 μm and a nickel content of more than 99.9%, activate it with hydrochloric acid solution with a mass concentration of 15% for 1 min, and then wash it with water multiple times. The water washing treatment is washing with deionized water at 10°C for 1 min until the pH of the washing solution is greater than 5. Finally, freeze dry it under vacuum to obtain activated nickel powder.

[0061] (2) The activated nickel powder obtained in step (1) was ultrasonically dispersed at a frequency of 20 kHz, an ultrasonic power of 500 W, a temperature of room temperature, and a time of 10 min. This was repeated three times. Then, the powder was placed in a 60% sodium hydroxide solution and heated under nitrogen protection at a rate of 6 °C / min. During the heating process, the stirring rate was 300 rpm.

[0062] (3) After the temperature of the reaction system in step (2) is raised to 150°C, oxygen is introduced to react. The partial pressure of the introduced oxygen is 0.1 MPa, the reaction time is 4 h, the stirring rate during the reaction is 200 rpm, and solid-liquid separation is performed after the reaction is completed.

[0063] (4) The solid obtained in step (3) is first washed with water at a temperature of 65°C for 10 minutes. After washing, it is acid-washed with a 0.5% hydrochloric acid solution for 10 minutes. After acid washing, it is washed with deionized water multiple times until the pH of the washing solution is neutral. The temperature of the deionized water is room temperature. The final solid obtained is γ-NiOOH.

[0064] Example 3

[0065] This embodiment provides a γ-NiOOH material, and the preparation method of the γ-NiOOH material is as follows:

[0066] (1) Select nickel powder with a particle size of about 80 μm and a nickel content of more than 99.9%, activate it with hydrochloric acid solution with a mass concentration of 20% for 1.5 min, and then wash it with water multiple times. The water washing treatment is to wash with deionized water at 20°C for 1.5 min until the pH of the washing solution is greater than 5. Finally, freeze dry it under vacuum to obtain activated nickel powder.

[0067] (2) The activated nickel powder obtained in step (1) was ultrasonically dispersed at a frequency of 20 kHz, an ultrasonic power of 500 W, a temperature of room temperature, and a time of 10 min. This was repeated three times. Then, the powder was placed in a 60% sodium hydroxide solution and heated under nitrogen protection at a rate of 7 °C / min. During the heating process, the stirring rate was 400 rpm.

[0068] (3) After the temperature of the reaction system in step (2) is raised to 150°C, oxygen is introduced to react. The partial pressure of the introduced oxygen is 0.1 MPa, the reaction time is 4 h, the stirring rate during the reaction is 200 rpm, and solid-liquid separation is performed after the reaction is completed.

[0069] (4) The solid obtained in step (3) is first washed with water at a temperature of 70°C for 15 minutes. After washing, it is acid-washed with a 1% hydrochloric acid solution for 20 minutes. After acid washing, it is washed with water multiple times with deionized water until the pH of the washing solution is neutral. The temperature of the deionized water is room temperature. The final solid obtained is γ-NiOOH.

[0070] Example 4

[0071] This embodiment provides a γ-NiOOH material, and the preparation method of the γ-NiOOH material is as follows:

[0072] (1) Select nickel powder with a particle size of about 80 μm and a nickel content of more than 99.9%, activate it with hydrochloric acid solution with a mass concentration of 25% for 2 min, and then wash it with water multiple times. The water washing treatment is to wash with deionized water at 30°C for 2 min until the pH of the washing solution is greater than 5. Finally, freeze dry it under vacuum to obtain activated nickel powder.

[0073] (2) The activated nickel powder obtained in step (1) was ultrasonically dispersed at a frequency of 20 kHz, an ultrasonic power of 500 W, a temperature of room temperature, and a time of 10 min. This was repeated three times. Then, the powder was placed in a 60% sodium hydroxide solution and heated under nitrogen protection at a rate of 8 °C / min. During the heating process, the stirring rate was 500 rpm.

[0074] (3) After the temperature of the reaction system in step (2) is raised to 150°C, oxygen is introduced to react. The partial pressure of the introduced oxygen is 0.1 MPa, the reaction time is 4 h, the stirring rate during the reaction is 200 rpm, and solid-liquid separation is performed after the reaction is completed.

[0075] (4) The solid obtained in step (3) is first washed with water at a temperature of 80°C for 20 minutes. After washing, it is acid-washed with a 2% hydrochloric acid solution for 25 minutes. After acid washing, it is washed with water multiple times with deionized water until the pH of the washing solution is neutral. The temperature of the deionized water is room temperature. The final solid obtained is γ-NiOOH.

[0076] Example 5

[0077] This embodiment provides a γ-NiOOH material, and the preparation method of the γ-NiOOH material is as follows:

[0078] (1) Select nickel powder with a particle size of about 80 μm and a nickel content of more than 99.9%, activate it with a 30% hydrochloric acid solution for 2.5 min, and then wash it with water multiple times. The water washing process is to wash with deionized water at 40°C for 2 min until the pH of the washing solution is greater than 5. Finally, freeze dry it under vacuum to obtain activated nickel powder.

[0079] (2) The activated nickel powder obtained in step (1) was ultrasonically dispersed at a frequency of 20 kHz, an ultrasonic power of 500 W, a temperature of room temperature, and a time of 10 min. This was repeated three times. Then, the powder was placed in a 60% sodium hydroxide solution and heated under nitrogen protection at a rate of 9 °C / min. During the heating process, the stirring rate was 600 rpm.

[0080] (3) After the temperature of the reaction system in step (2) is raised to 150°C, oxygen is introduced to react. The partial pressure of the introduced oxygen is 0.1 MPa, the reaction time is 4 h, the stirring rate during the reaction is 200 rpm, and solid-liquid separation is performed after the reaction is completed.

[0081] (4) The solid obtained in step (3) is first washed with water at a temperature of 80°C for 25 minutes. After washing, it is acid-washed with a 3% hydrochloric acid solution for 30 minutes. After acid washing, it is washed with water multiple times with deionized water until the pH of the washing solution is neutral. The temperature of the deionized water is room temperature. The final solid obtained is γ-NiOOH.

[0082] Example 6

[0083] This embodiment provides a γ-NiOOH material, and the preparation method of the γ-NiOOH material is as follows:

[0084] (1) Select nickel powder with a particle size of about 80 μm and a nickel content of more than 99.9%, activate it with hydrochloric acid solution with a mass concentration of 37% for 3 min, and then wash it with water multiple times. The water washing process is to wash with deionized water at 40°C for 2 min until the pH of the washing solution is greater than 5. Finally, freeze dry it under vacuum to obtain activated nickel powder.

[0085] (2) The activated nickel powder obtained in step (1) was ultrasonically dispersed at a frequency of 20 kHz, an ultrasonic power of 500 W, a temperature of room temperature, and a time of 10 min. This was repeated three times. Then, the powder was placed in a 60% sodium hydroxide solution and heated under nitrogen protection at a rate of 10 °C / min. During the heating process, the stirring rate was 400 rpm.

[0086] (3) After the temperature of the reaction system in step (2) is raised to 150°C, oxygen is introduced to react. The partial pressure of the introduced oxygen is 0.1 MPa, the reaction time is 4 h, the stirring rate during the reaction is 200 rpm, and solid-liquid separation is performed after the reaction is completed.

[0087] (4) The solid obtained in step (3) is first washed with water at a temperature of 80°C for 30 minutes. After washing, it is acid-washed with a 1% hydrochloric acid solution for 10 minutes. After acid washing, it is washed with water multiple times with deionized water until the pH of the washing solution is neutral. The temperature of the deionized water is room temperature. The final solid obtained is γ-NiOOH.

[0088] Example 7

[0089] This embodiment provides a γ-NiOOH material, and the preparation method of the γ-NiOOH material is as follows:

[0090] (1) Select nickel powder with a particle size of about 80 μm and a nickel content of more than 99.9%, activate it with a 30% hydrochloric acid solution for 3 min, and then wash it with water multiple times. The water washing process is to wash with deionized water at 40°C for 2 min until the pH of the washing solution is greater than 5. Finally, freeze dry it under vacuum to obtain activated nickel powder.

[0091] (2) The activated nickel powder obtained in step (1) was ultrasonically dispersed at a frequency of 20 kHz, an ultrasonic power of 500 W, a temperature of room temperature, and a time of 10 min. This was repeated three times. Then, the powder was placed in a 60% sodium hydroxide solution and heated under nitrogen protection at a heating rate of 8 °C / min. During the heating process, the stirring rate was 600 rpm.

[0092] (3) After the temperature of the reaction system in step (2) is raised to 150°C, oxygen is introduced to react. The partial pressure of the introduced oxygen is 0.1 MPa, the reaction time is 4 h, the stirring rate during the reaction is 200 rpm, and solid-liquid separation is performed after the reaction is completed.

[0093] (4) The solid obtained in step (3) is first washed with water at a temperature of 80°C for 30 minutes. After washing, it is acid-washed with a 1% hydrochloric acid solution for 10 minutes. After acid washing, it is washed with water multiple times with deionized water until the pH of the washing solution is neutral. The temperature of the deionized water is room temperature. The final solid obtained is γ-NiOOH.

[0094] Example 8

[0095] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 7. Except that the concentration of sodium hydroxide solution in step (2) is adjusted to 70%, the rest is the same as that of Example 7.

[0096] Example 9

[0097] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 7. Except for adjusting the concentration of sodium hydroxide solution in step (2) to 80%, the rest is the same as that of Example 7.

[0098] Example 10

[0099] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 7. Except for adjusting the concentration of sodium hydroxide solution in step (2) to 90%, the rest is the same as that of Example 7.

[0100] Example 11

[0101] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 8. Except for adjusting the reaction temperature in step (3) to 180°C, the rest is the same as that of Example 8.

[0102] Example 12

[0103] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 8. Except for adjusting the reaction temperature in step (3) to 210℃, the rest is the same as that of Example 8.

[0104] Example 13

[0105] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 8. Except for adjusting the reaction temperature in step (3) to 240℃, the rest is the same as that of Example 8.

[0106] Example 14

[0107] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 8. Except for adjusting the reaction temperature in step (3) to 270°C, the rest is the same as that of Example 8.

[0108] Example 15

[0109] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 8. Except for adjusting the reaction temperature in step (3) to 300℃, the rest is the same as that of Example 8.

[0110] Example 16

[0111] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 13. Except for adjusting the partial pressure of oxygen introduced in step (3) to 2 MPa, the rest is the same as that of Example 13.

[0112] Example 17

[0113] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 13. Except for adjusting the partial pressure of oxygen introduced in step (3) to 4 MPa, the rest is the same as that of Example 13.

[0114] Example 18

[0115] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 13. Except that the partial pressure of oxygen introduced in step (3) is adjusted to 6 MPa, the rest is the same as that of Example 13.

[0116] Example 19

[0117] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 13. Except for adjusting the partial pressure of oxygen introduced in step (3) to 8 MPa, the rest is the same as that of Example 13.

[0118] Example 20

[0119] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 18. Except for adjusting the reaction time in step (3) to 12h, the rest is the same as that of Example 18.

[0120] Example 21

[0121] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 18. Except for adjusting the reaction time in step (3) to 24h, the rest is the same as that of Example 18.

[0122] Example 22

[0123] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 18. Except for adjusting the reaction time in step (3) to 36h, the rest is the same as that of Example 18.

[0124] Example 23

[0125] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 18. Except for adjusting the reaction time in step (3) to 48h, the rest is the same as that of Example 18.

[0126] Example 24

[0127] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 21. Except for adjusting the stirring rate of step (3) to 300 rpm, the rest is the same as that of Example 21.

[0128] Example 25

[0129] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 21. Except for adjusting the stirring rate of step (3) to 400 rpm, the rest is the same as that of Example 21.

[0130] Example 26

[0131] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 21. Except for adjusting the stirring rate of step (3) to 500 rpm, the rest is the same as that of Example 21.

[0132] Example 27

[0133] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 21. Except for adjusting the stirring rate of step (3) to 600 rpm, the rest is the same as that of Example 21.

[0134] Example 28

[0135] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 27. Except for adjusting the particle size of the nickel powder in step (1) to 50 nm, the rest is the same as that of Example 27.

[0136] Example 29

[0137] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 27. Except for adjusting the particle size of the nickel powder in step (1) to 200 nm, the rest is the same as that of Example 27.

[0138] Example 30

[0139] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 27. Except for adjusting the particle size of the nickel powder in step (1) to 10 μm, the rest is the same as that of Example 27.

[0140] Example 31

[0141] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 27. Except for adjusting the particle size of the nickel powder in step (1) to 50 μm, the rest is the same as that of Example 27.

[0142] Example 32

[0143] This embodiment provides a γ-NiOOH material. The preparation method of the γ-NiOOH material is different from that of Example 27. Except for adjusting the particle size of the nickel powder in step (1) to 100 μm, the rest is the same as that of Example 27.

[0144] Comparative Example 1

[0145] Except for the nickel powder not undergoing activation treatment, the conditions in this comparative example are the same as those in Example 32.

[0146] Comparative Example 2

[0147] Except for the fact that the heating was carried out in air, the conditions in this comparative example were the same as those in Example 32.

[0148] The particle size of the γ-NiOOH materials prepared in Examples 1-32 and Comparative Examples 1 and 2 was tested, and the results are shown in Table 1.

[0149] The conversion rate is calculated as the actual mass of γ-NiOOH produced divided by the theoretical mass of γ-NiOOH produced from nickel powder. The particle size is determined using a laser particle size analyzer.

[0150] The γ-NiOOH prepared in Example 32 was subjected to SEM and XRD tests, and the results are as follows: Figure 1 and 2 As shown, from Figure 1 It can be seen that the generated γ-NiOOH has a multilayer structure and is roughly hexagonal in shape; Figure 2 It can be seen that the position of the diffraction peak is consistent with that of γ-NiOOH.

[0151]

[0152]

[0153] The applicant declares that the detailed structural features of the present invention are illustrated through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the components selected in the present invention, additions of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0154] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0155] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0156] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for preparing layered nickel hydroxyl oxide, characterized in that, The preparation method includes: Nickel powder is activated to obtain activated nickel powder; the activation method includes placing the nickel powder in an acidic solution to remove oxides from the surface of the nickel powder; The activated nickel powder is placed in an alkaline solution with a concentration of 60-80 wt%, heated to the reaction temperature under a protective atmosphere, and oxygen is introduced to carry out the reaction. The partial pressure of the oxygen is 0.1-8 MPa, the reaction time is 4-48 h, and the reaction temperature is 150-300 °C. After the reaction, solid-liquid separation is performed to obtain the layered nickel hydroxy oxide.

2. The preparation method according to claim 1, characterized in that, The acidic solution includes hydrochloric acid with a concentration of 10-37 wt%.

3. The preparation method according to claim 1, characterized in that, The activation time is 0.5 to 3 minutes.

4. The preparation method according to claim 1, characterized in that, After the activation treatment, the activated nickel powder is subjected to a first cleaning treatment.

5. The preparation method according to claim 1, characterized in that, The activated nickel powder is ultrasonically dispersed before being placed in an alkaline solution.

6. The preparation method according to claim 1, characterized in that, The alkaline solution includes an aqueous solution of sodium hydroxide and / or potassium hydroxide.

7. The preparation method according to claim 1, characterized in that, The heating rate is 5~10 °C / min.

8. The preparation method according to claim 1, characterized in that, The reaction is carried out under stirring at a speed of 200-600 rpm.

9. The preparation method according to claim 1, characterized in that, The preparation method further includes sequentially washing the solid obtained after solid-liquid separation with water and acid.

10. The preparation method according to any one of claims 1-9, characterized in that, The preparation method includes: The nickel powder is placed in an acidic solution to remove oxides from its surface. The acidic solution includes hydrochloric acid with a concentration of 10-37 wt%. The activation time is 0.5-3 min to obtain activated nickel powder. The activated nickel powder is ultrasonically dispersed, and then placed in an alkaline solution with a concentration of 60-80 wt%. Under a protective atmosphere, the temperature is increased to a reaction temperature of 150-300 °C at a heating rate of 5-10 °C / min. Oxygen is introduced to carry out the reaction, with a partial pressure of 0.1-8 MPa. The reaction time is 4-48 h. The reaction is carried out under stirring at a stirring rate of 200-600 rpm. After the reaction, solid-liquid separation is performed, and the solid obtained after solid-liquid separation is washed with water and acid in sequence to obtain the layered nickel hydroxy oxide.

Images