Preparation method for directly growing CuCoO2 on foamed nickel and application of CuCoO2

Abstract

The invention discloses a preparation method and application for directly growing CuCoO2 on foamed nickel, and the preparation method comprises the following steps: dissolving copper nitrate, cobalt nitrate and a mineralizer in a solvent, intensely stirring to form a suspension A, then transferring the suspension A into a high-pressure kettle, and carrying out vacuum drying to obtain CuCoO2; meanwhile, the foamed nickel is placed in a polytetrafluoroethylene flower basket and then placed in an autoclave to be heated for a hydrothermal reaction, and after the hydrothermal reaction is finished, the foamed nickel is cooled to the room temperature. According to the method, the CuCoO2 electrode with the foamed nickel substrate can be prepared in one step, compared with a method for preparing CuCoO2 powder and then transferring the CuCoO2 powder to an electrode plate, the needed time is short, operation is easy, the electrode material is uniform, and the method can be widely applied to related fields as an efficient photoelectric functional material electrode preparation method.

Description

Technical Field

[0001] The invention relates to the technical field of metal oxides, and in particular to a preparation method for directly growing CuCoO2 on nickel foam and application thereof. Background Art

[0002] In recent years, copper-based metal oxide photocathodes have attracted extensive attention from researchers due to their excellent photoelectric properties, high carrier mobility, non-toxicity, abundant content in the earth's crust, environmental friendliness, and low synthesis cost. Copper-based metal oxides can be classified into: binary copper-based oxides and ternary copper-based oxides (copper iron ore CuMO2-type oxides, spinel CuM2O3-type oxides, etc. (M=Fe, Al, Co, Ga, etc.). They have a wide bandgap distribution range. In addition, the conduction band edges of most copper-based metal oxides are above the hydrogen evolution potential, so they have good thermodynamic conditions in the water reduction reaction, which lays a certain foundation for their application in the field of photoelectric conversion.

[0003] However, since the conventional preparation products of ternary metal oxides are all in powder form, the PEC test and application of them require brushing or dripping of the powder samples again, which makes the process more cumbersome. In addition, due to the poor contact between the powder and the substrate, the hydrogen or oxygen evolution performance of the sample cannot be fully exerted. Based on this, it is very necessary to study a preparation method of growing ternary metal oxide CuCoO2 directly on a substrate to solve the above problems. Summary of the invention

[0004] The purpose of the present invention is to design a preparation method for directly growing CuCoO2 on nickel foam, which has the advantages of low cost, simple operation, high sample performance and the like.

[0005] In order to achieve the above technical effects, the present invention is implemented by the following technical scheme: A preparation method for directly growing CuCoO2 on nickel foam, characterized in that it consists of the following steps:

[0006] S1, washing the nickel foam in dilute hydrochloric acid, deionized water, and an alcohol solution in sequence and drying with nitrogen gas to obtain a clean nickel foam;

[0007] S2. Weigh copper nitrate and cobalt nitrate in a molar ratio of copper nitrate: cobalt nitrate = 1:0.8-2, then dissolve the copper nitrate and cobalt nitrate in 70 mL of deionized water, and stir evenly for 0.5-3 h to obtain solution A;

[0008] S3, adding a mineralizer to the solution A obtained in S2, and stirring vigorously for 0.5 to 3 hours to obtain a suspension B;

[0009] S4, placing the cleaned nickel foam obtained in S1 in a polytetrafluoroethylene basket and placing it in an autoclave;

[0010] S5. Transfer the suspension B in step S3 to the inner lining of the autoclave, seal the autoclave body, place it in an oven and heat it to 100-200° C., and perform a hydrothermal reaction for 10-24 hours. After the hydrothermal reaction is completed, wait for the autoclave body to naturally cool to room temperature, open the autoclave body and take out the obtained product, that is, obtain the CuCoO2 material grown directly on the nickel foam.

[0011] Furthermore, in S1, the cleaning is specifically as follows: placing the nickel foam in a centrifuge tube or a beaker, adding 1 mol / L hydrochloric acid in sequence, placing it in an ultrasonic bath for 8 to 12 minutes, and then pouring out the hydrochloric acid solution; adding deionized water, placing it in an ultrasonic bath for 8 to 12 minutes, and then pouring out the deionized water; and finally adding anhydrous ethanol, placing it in an ultrasonic bath for 8 to 12 minutes.

[0012] Furthermore, in S3, the mineralizer is sodium hydroxide, potassium hydroxide or a mixture of the two.

[0013] Furthermore, in S3, the strong stirring is stirring at a stirring speed of 290 to 310 r / min.

[0014] Furthermore, in S4, the autoclave is a stainless steel autoclave lined with polytetrafluoroethylene.

[0015] Furthermore, in S5, the filling ratio of the suspension B transferred to the lining of the autoclave is 30-80%.

[0016] Another object of the present invention is to provide an application of CuCoO2 directly grown on nickel foam, characterized in that the CuCoO2 directly grown on nickel foam is used in the preparation of high-efficiency photoelectric functional material electrodes.

[0017] The beneficial effects of the present invention are:

[0018] The method of growing CuCoO2 directly on nickel foam adopted in the present invention has a relatively mature technical route and is inexpensive, and overcomes the defects in the operation of preparing ternary copper-based oxides to prepare PEC electrodes in the current technology;

[0019] The preparation process provided by the present invention has the advantages of simple operation, easy control of parameters, green environmental protection, high yield, low temperature and fast, low cost, etc. It can be widely used in the preparation of new photoelectric functional materials based on delafossilite CuCoO2, which is beneficial to the development and industrialization of new photoelectric functional materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 It is a schematic diagram of the structure of the reaction of the present invention;

[0022] Figure 2 The X-ray crystal diffraction pattern of the sample prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Example 1

[0025] A hydrothermal preparation method for directly growing CuCoO2 from nickel foam, the method is as follows:

[0026] 1. Foam nickel cleaning:

[0027] Put the nickel foam in a centrifuge tube or beaker, add 1 mol / L hydrochloric acid, deionized water, and anhydrous ethanol in sequence, put it in an ultrasonic bath, sonicate for 10 min respectively, and then blow dry with nitrogen.

[0028] 2. Preparation of CuCoO2 / nickel foam:

[0029] 2.1. Dissolve 15 mmol Cu(NO3)2·3H2O and 15 mmol Co(NO3)3·6H2O in 70 mL of deionized water and stir for 0.5 hours to obtain a mixed solution A.

[0030] 2.2. Add 0.1 mol of sodium hydroxide to the suspension under vigorous stirring, and continue to vigorously stir for 1 hour at a stirring rate of 300 rpm to obtain suspension B;

[0031] 2.3. Transfer the mixed solution B in step 2.2 into a 100 mL stainless steel autoclave lined with polytetrafluoroethylene with a filling ratio of 70%. After sealing the autoclave, heat it in an oven at 140°C for 24 hours. After the reaction is completed, wait for the autoclave to cool naturally to room temperature, open the autoclave and take out the desired material.

[0032] The X-ray crystal diffraction pattern of the sample prepared in this embodiment is as follows Figure 2 As shown, the diffraction peak of Ni and the main diffraction peak of CuCoO2 (within the black dotted box) can be seen in the figure.

[0033] Example 2

[0034] This embodiment provides a method for preparing a CuCoO2 electrode by a drop coating method conventionally used in preparing a CuCoO2 electrode, comprising the following steps:

[0035] 1. Preparation of CuCoO2 powder

[0036] 1.1 Dissolve copper nitrate and cobalt nitrate in 70 mL of deionized water, stir for 1 hour, then add 0.1 mol NaOH and stir for another 2 hours to form suspension A;

[0037] 1.2 Add suspension A to a 100 mL polytetrafluoroethylene reactor and heat it in an oven at 160°C for 24 hours. After the reaction is completed, wait for the reactor to cool naturally to room temperature, open the reactor and take out the reaction solution. The reaction product is washed alternately with deionized water and anhydrous ethanol and centrifuged 6 times at a centrifugal speed of 7000 rpm for 10 minutes each time. After drying at 60°C for 12 hours, CuCoO2 powder is obtained.

[0038] 2. Nickel foam cleaning:

[0039] Put the nickel foam in a centrifuge tube or beaker, add 1 mol / L hydrochloric acid, deionized water, and anhydrous ethanol in sequence, put it in an ultrasonic bath, sonicate for 10 min respectively, and then blow dry with nitrogen.

[0040] 3. Preparation of CuCoO2 Electrode

[0041] 3.1 Weigh 0.02 g of the CuCoO2 powder prepared in step 1.2 into a centrifuge tube, then add 1 mL of isopropanol solution and sonicate for 0.5 h;

[0042] 3.2 Use a pipette to pipette 50 μL of the solution in step 3.1 and drop it on the nickel foam. Anneal it in a muffle furnace at 300°C for 2 hours.

[0043] Compared with Example 1, Example 2 has complicated steps and requires high temperature annealing, which has certain changes on the sample and substrate, and may cause inaccurate performance test of the electrode. Therefore, it is very necessary to design a preparation method for growing CuCoO2 directly on nickel foam.

Claims

1. A method for preparing CuCoO2 by directly growing it on nickel foam, characterized in that: It consists of the following steps: S1, washing the nickel foam in dilute hydrochloric acid, deionized water, and an alcohol solution in sequence and drying with nitrogen gas to obtain a clean nickel foam; S2. Weigh copper nitrate and cobalt nitrate in a molar ratio of copper nitrate: cobalt nitrate = 1:0.8-2, then dissolve the copper nitrate and cobalt nitrate in 70 mL of deionized water, and stir evenly for 0.5-3 h to obtain solution A; S3, adding a mineralizer to the solution A obtained in S2, and stirring vigorously for 0.5 to 3 hours to obtain a suspension B; S4, placing the cleaned nickel foam obtained in S1 in a polytetrafluoroethylene basket and placing it in an autoclave; S5. Transfer the suspension B in step S3 to the inner lining of the autoclave, seal the autoclave body, place it in an oven and heat it to 100-200° C., and perform a hydrothermal reaction for 10-24 hours. After the hydrothermal reaction is completed, wait for the autoclave body to naturally cool to room temperature, open the autoclave body and take out the obtained product, that is, obtain the CuCoO2 material grown directly on the nickel foam.

2. A method for preparing CuCoO2 by directly growing it on nickel foam according to claim 1, characterized in that: In S1, the cleaning is specifically to place the nickel foam in a centrifuge tube or beaker and sequentially use 1 mol / L hydrochloric acid, deionized water, and anhydrous ethanol as cleaning solutions for cleaning. During cleaning, after each cleaning solution is poured in, the centrifuge tube or beaker is placed in an ultrasonic bath for 8 to 12 minutes, and the previous cleaning solution needs to be poured out when the next cleaning solution is used for cleaning.

3. The method for preparing CuCoO2 by directly growing it on nickel foam according to claim 1, characterized in that: In S3, the mineralizer is sodium hydroxide, potassium hydroxide or a mixture of the two.

4. The method for preparing CuCoO2 by directly growing it on nickel foam according to claim 1, characterized in that: In S3, the strong stirring is stirring at a stirring speed of 290 to 310 r / min.

5. The method for preparing CuCoO2 by directly growing it on nickel foam according to claim 1, characterized in that: In S4, the autoclave is a stainless steel autoclave lined with polytetrafluoroethylene.

6. The method for preparing CuCoO2 by directly growing it on nickel foam according to claim 1, characterized in that: In S5, the suspension B is transferred to the inner lining of the autoclave at a filling ratio of 30 to 80%.

7. An application of directly growing CuCoO2 on nickel foam, characterized in that: The application of CuCoO2 directly grown on the nickel foam in the preparation of high-efficiency photoelectric functional material electrodes.

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