Aqueous copper-doped NiO x Preparation method, product and application of nanomaterial

Abstract

The present invention belongs to the technical field of solar cells, and particularly relates to a preparation method of an aqueous copper-doped NiO x nanomaterials, its products and applications. A layer of NiO x is grown on the surface of the prepared Cu:NiO x nanomaterial shell. By using one or more of alcohol ethers, alcohol amines, glycols, and polyethylene glycols as surface ligands of the nanomaterials and limiting the carbon chain number to 2-4, it is used to provide aqueous groups (-OH, -NH2). The purpose is to be dispersible in water without affecting its conductivity, and it can also provide binding sites chelated with In and Sn on ITO, so that the copper-doped nickel oxide dispersion has high oxygen affinity, good leveling property, excellent film-forming property, good spreading property, adhesion, and compactness on the FTO substrate.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar cells, and particularly relates to a preparation method, product and application of an aqueous copper-doped NiO x nanomaterial. Background Art

[0002] With the continuous development of technology, perovskite solar cells have broad development prospects because of their advantages such as high limiting conversion efficiency, low production cost, simple preparation process, and high flexibility, and can be applied to fields such as photovoltaic power generation. Copper-doped NiO x As a commonly used hole transport layer material in inverted perovskite solar cells, it has advantages such as low cost and low synthesis temperature, so it is widely used in photovoltaic devices.

[0003] However, conventional copper-doped NiO x nanomaterials have poor dispersibility in water and are prone to aggregation. Secondly, the hole mobility is not stable enough due to the influence of the concentration of trivalent Ni, the Cu doping concentration, and the Cu(2+) / Cu(1+) concentration ratio. Due to poor dispersibility, the affinity on ITO (tin-doped indium oxide) and FTO (fluorine-doped tin oxide conductive glass) substrates is relatively low when preparing photovoltaic devices, and problems such as uneven film surface, large leakage current, and increased series resistance are likely to occur in the spin-coated film, ultimately resulting in a low light conversion rate of the device. These problems greatly limit its application in the field of perovskite solar cells. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method, product and application of an aqueous copper-doped NiO x nanomaterial to solve the problems of low hole conductivity, poor hydrophilicity, easy reduction of copper-doped NiO x nanomaterials, and low light conversion efficiency of the fabricated devices.

[0005] A preparation method of an aqueous copper-doped NiO x nanomaterial includes the following steps:

[0006] S1. Mix one or more of alcohol ethers, alcohol amines, glycols, and polyethylene glycols with a solvent to form a first reaction system;

[0007] S2. Mix a nickel salt, a copper salt, and the first reaction system at 10-30°C to obtain a second reaction system;

[0008] S3. Add alkali with a mass fraction of 10%-50% to the second reaction system, control the pH at 8-12, and obtain a Cu:Ni(OH)2 sol dispersion system after reacting for 0.2-24 h;

[0009] S4. Centrifuge the above-mentioned Cu:Ni(OH)2 sol dispersion system, wash it with water multiple times until no anions exist;

[0010] S5. Calcinate the Cu:Ni(OH)2 sol in S5 at 200°C-300°C for 1-24 h to obtain a black Cu:NiO x calcined body;

[0011] S6. Ball-mill the Cu:NiO x calcined body in a ball mill for 0.5-24 h to obtain Cu:NiO x nano powder;

[0012] S7. Ultrasonic the Cu:NiO x nano powder under an ultrasonic probe for 0.1-10 h to obtain a Cu:NiO x nano aqueous dispersion.

[0013] Furthermore, after step S3, it also includes: adding nickel salt and alkali to the Cu:Ni(OH)2 sol dispersion system obtained in S3, controlling the pH at 8-12, and reacting for 0.5-12 h.

[0014] Furthermore, the alcohol ether in S1 is a straight-chain alcohol ether with 3-5 carbon atoms; the alcohol amine is a straight-chain alcohol amine with 2-5 carbon atoms; the polyol is a glycol with 2-6 carbon atoms; the solvent is one of water, methanol, and ethanol.

[0015] Furthermore, the volume ratio of the total volume of the alcohol ether, alcohol amine, glycol, and polyethylene glycol in the first reaction system to the volume of the solvent is: (0.1-0.5):1.

[0016] Furthermore, in terms of the amount of substance, the overall feeding ratio of the nickel salt and alkali in S3 is 1:(0.5-3).

[0017] The water-based copper-doped NiO x nano material prepared by the aforementioned preparation method has copper-doped NiO x inside, and an organic ligand outside. The organic ligand is one or more of alcohol ether, alcohol amine, glycol, and polyethylene glycol.

[0018] The water-based copper-doped NiO x nano material prepared by another aforementioned preparation method has copper-doped NiO x as the core inside, and a layer of NiO x as the shell outside. The shell NiO xThe outer surface is an organic ligand, which is one or more of alcohol ethers, alkanolamines, glycols, and polyethylene glycols. The semiconductor configuration is a type I structure, that is, the conduction band bottom and valence band top of one material are both within the band gap of another material.

[0019] Furthermore, the content of the organic ligand accounts for 5%-30% of the total weight of the entire nanomaterial. The particle size of the nanomaterial is 3-10 nm, and the band gap is 3.6 eV-4.0 eV.

[0020] Furthermore, in terms of the amount of substance, this copper-doped NiO x In the nanomaterial, the ratio of Ni:Cu is 1:(0.01-0.5), and NiO x includes nickelous oxide and nickel peroxide, and the molar ratio of trivalent nickel to divalent nickel is 0.1-1.

[0021] As described above for the two structures of aqueous copper-doped NiO x Application of the nanomaterial as a hole transport layer material for perovskite solar cells.

[0022] The beneficial effects of the present invention are as follows:

[0023] In the present invention, one or more of alcohol ethers, alkanolamines, glycols, and polyethylene glycols are used as surface ligands of the nanomaterial, and the carbon chain number is limited to 2-4 to provide hydrophilic groups (-OH, -NH2). The purpose is to be dispersible in water, not affect its conductivity, and also provide binding sites for chelation with In and Sn on ITO, so that the copper-doped nickel oxide dispersion has high oxygen affinity, good leveling property, excellent film-forming property, good spreading property, adhesion, and denseness on the FTO substrate;

[0024] The doping of copper in nickel oxide of the present invention can effectively reduce the excitation energy level of majority carriers (holes) in the material; secondly, the prepared core-shell structured nanomaterial not only optimizes the energy level structure but also significantly enhances the dispersibility of the material in water, thereby improving the device performance while effectively improving the storage performance of the material. The entire reaction is carried out at room temperature, which is green, environmentally friendly, and pollution-free, avoiding the occurrence of hazards. Description of the Drawings

[0025] Figure 1 is the core-shell structure schematic diagram of Cu:NiO x @NiO x prepared by the present invention.

[0026] Figure 2 is the Cu:NiO x @NiO xTEM image of nanoparticles (Transmission Electron Microscope image).

[0027] Figure 3 Cu:NiO prepared according to the present invention x @NiO x XRD pattern of nanoparticles (X-Ray Diffraction pattern). Detailed implementation manners

[0028] The technical solution of the present invention will be further described below through examples and drawings.

[0029] The present invention first provides a method for preparing an aqueous copper-doped NiO x nanomaterials, comprising the following steps:

[0030] S1. Mix one or more of alcohol ethers, alcohol amines, glycols, polyethylene glycols with a solvent to form a first reaction system;

[0031] S2. At 10-30 °C, mix a nickel salt, a copper salt and the first reaction system to obtain a second reaction system;

[0032] S3. Add an alkali with a mass fraction of 10%-50% to the second reaction system, control the pH at 8-12, and react for 0.2-24 h to obtain a Cu:Ni(OH)2 sol dispersion system;

[0033] S4. Centrifuge the above Cu:Ni(OH)2 sol dispersion system, wash it with water multiple times until no anions are present;

[0034] S5. Calcinate the Cu:Ni(OH)2 sol in S5 at 200 °C - 300 °C for 1-24 h to obtain a black Cu:NiO x @NiO x calcined body;

[0035] S6. Ball-mill the Cu:NiO x calcined body in a ball mill for 0.5-24 h to obtain Cu:NiO x @NiO x nano powder;

[0036] S7. Ultrasonic the Cu:NiO x nano powder under an ultrasonic probe for 0.1-10 h to obtain Cu:NiO x @NiO x nano aqueous dispersion.

[0037] In order to obtain a core-shell structure Cu:NiO x @NiO x, Nickel salts and bases are added to the Cu:Ni(OH)2 sol dispersion system obtained in S3, the pH is controlled at 8 - 12, and the reaction is carried out for 0.5 - 12 h to obtain a Ni(OH)2 shell; then subsequent steps are carried out.

[0038] The present invention includes aqueous copper-doped NiO nanomaterials with two structures. x In one structure, the interior is copper-doped NiO. x The exterior is an organic ligand, and the organic ligand is one or more of alcohol ethers, alkanolamines, glycols, and polyethylene glycols. In the other structure, the interior is copper-doped NiO. x As the core, and outside the core is another layer of NiO. x As the shell, and the outer surface of the shell NiO x is an organic ligand, and the organic ligand is one or more of alcohol ethers, alkanolamines, glycols, and polyethylene glycols. The semiconductor configuration is a type I structure, and the type I structure means that the bottom of the conduction band and the top of the valence band of one material are both within the band gap of another material.

[0039] The alcohol ether described in S1 is a straight-chain alcohol ether with 3 - 5 carbon atoms in the carbon chain. For example: one of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, propylene glycol methyl ether, and propylene glycol ethyl ether. The alkanolamine described is a straight-chain alkanolamine with 2 - 5 carbon atoms in the carbon chain. For example: one of ethanolamine, propanolamine, butanolamine, and pentanolamine. The polyol is a glycol with 2 - 6 carbon atoms in the carbon chain. For example: one of ethylene glycol, diethylene glycol, and triethylene glycol.

[0040] The nickel salts in S2 and S4 can be selected but are not limited to nickel nitrate and its hydrates, nickel chloride and its hydrates, nickel acetate and its hydrates, nickel sulfate and its hydrates, nickel bromide and its hydrates, nickel acetylacetonate and its hydrates, nickel dibutyldithiocarbamate, nickel diethyldithiocarbamate, nickel oxalate, nickel phosphate, nickel xanthate, nickel ethylenediaminetetraacetate, nickel isopropoxide, nickel 8-hydroxyquinoline, nickel stearate, nickel hypophosphite and its hydrates, nickel fluoride, nickel basic carbonate, nickel perchlorate, nickel benzoate, nickel thiocyanate, nickel trifluoromethanesulfonate.

[0041] The copper salts in S2 can be selected but are not limited to copper nitrate and its hydrates, copper chloride and its hydrates, copper acetate and its hydrates, copper sulfate and its hydrates, copper bromide and its hydrates, copper acetylacetonate and its hydrates, copper dibutyldithiocarbamate, copper diethyldithiocarbamate, copper oxalate, copper phosphate, copper xanthate, copper citrate, copper ethylenediaminetetraacetate, copper 8-hydroxyquinoline.

[0042] The bases in S3 can be selected but are not limited to one or more of ammonia water, sodium hydroxide, potassium hydroxide, and tetramethylammonium hydroxide.

[0043] According to another aspect of the present invention, a perovskite solar cell is provided, which includes an anode, a hole transport layer, a light absorption layer, an electron transport layer, and a cathode. The hole transport layer is composed of the above-mentioned copper-doped NiO x The nanoparticle aqueous dispersion is prepared by one of spin coating, printing, spraying, and blade coating.

[0044] Example 1

[0045] The following is the synthesis of the shell-free Cu:NiO x nanomaterials. Ethanolamine is used as a surface ligand and connected to the surface of the copper-doped nickel oxide nanoparticles, including the following steps:

[0046] S1. Mix 10 ml of ethanolamine with 1 L of water to form a first reaction system;

[0047] S2. At 20 °C, mix 0.25 mol of nickel nitrate, 0.01 mol of copper nitrate, and the first reaction system to obtain a second reaction system;

[0048] S3. Add 4 mol / L of NaOH to the second reaction system, control the pH at 10, and react for 2 h to obtain a green sol dispersion system of Cu:Ni(OH)2;

[0049] S4. Centrifuge the above-mentioned Cu:Ni(OH)2 sol dispersion system and wash it 3 times with water until the nitrate ions are completely removed;

[0050] S5. Calcinate the Cu:Ni(OH)2 sol in S4 at 280 °C for 2 h to obtain a black Cu:NiO x calcined body;

[0051] S6. Ball mill the Cu:NiO x calcined body in a ball mill for 12 h to obtain Cu:NiO x nano powder;

[0052] S7. Ultrasonicate the Cu:NiO x nano powder under an ultrasonic probe for 1 h to obtain a Cu:NiO x nano aqueous dispersion.

[0053] Example 2

[0054] The following is the synthesis of the core-shell Cu:NiO x @NiO x nanomaterials. Ethanolamine and ethylene glycol methyl ether are used as surface ligands and connected to the surface of the copper-doped nickel oxide nanoparticles, including the following steps:

[0055] S1. Mix 8 ml of ethanolamine, 2 ml of ethylene glycol methyl ether with 1 L of ethanol to form a first reaction system;

[0056] S2. At 15 °C, 0.3 mol of nickel chloride, 0.008 mol of copper chloride and the first reaction system are mixed to obtain a second reaction system;

[0057] S3. 10% ammonia water is added to the second reaction system, and the pH is controlled at 9. After reacting for 1 h, a Ni(OH)2 sol dispersion system is obtained;

[0058] In order to obtain a core-shell structure of Cu:NiO x @NiO x , 0.05 mol of nickel chloride is added to the above-mentioned Cu:Ni(OH)2 sol dispersion system. After reacting for 0.5 h, 10% ammonia water is added, and the pH is controlled at 10. After reacting for 0.5 h, a Ni(OH)2 shell layer is obtained;

[0059] S4. Centrifuge the above-mentioned Cu:NiO x @NiO x sol dispersion system, and wash it with water 3 times until the ammonium ions are completely removed;

[0060] S5. The Cu:Ni(OH)2 sol in S5 is calcined at 290 °C for 3 h to obtain a black Cu:NiO x calcined body;

[0061] S6. The Cu:NiO x calcined body is ball-milled in a ball mill for 3 h to obtain Cu:NiO x nano powder;

[0062] S7. The Cu:NiO x nano powder is ultrasonically treated under an ultrasonic probe for 0.5 h to obtain a Cu:NiO x nano aqueous dispersion.

[0063] Example 3

[0064] The following is the synthesis of a core-shell structured Cu:NiO x @NiO x nano material. N-propanolamine, polyethylene glycol 200, and ethylene glycol are used as surface ligands and connected to the surface of copper-doped nickel oxide nanoparticles, including the following steps:

[0065] S1. 10 ml of n-propanolamine, 2 ml of polyethylene glycol 200, and 1 ml of ethylene glycol are mixed with water to form a first reaction system;

[0066] S2. At 30 °C, 0.3 mol of nickel sulfate, 0.006 mol of copper sulfate and the first reaction system are mixed to obtain a second reaction system;

[0067] S3. Add 4 mol / L KOH to the second reaction system, control the pH at 11, and obtain a Cu:Ni(OH)2 sol dispersion system after reacting for 1 h;

[0068] To obtain the core-shell structure Cu:NiO x @NiO x , add 0.04 mol nickel sulfate and 0.006 mol copper sulfate to the above Cu:Ni(OH)2 sol dispersion system, react for 0.5 h, then add 4 mol / L KOH, control the pH at 10, and react for 0.5 h to obtain a Ni(OH)2 shell layer;

[0069] S4. Centrifuge the above Cu:Ni(OH)2 sol dispersion system and wash it 3 times with water until the sulfate ions are eluted;

[0070] S5. Calcinate the Cu:Ni(OH)2 sol in S5 at 250 °C for 3.5 h to obtain a black Cu:NiO x calcined body;

[0071] S6. Ball-mill the Cu:NiO x calcined body in a ball mill for 9 h to obtain Cu:NiO x nano powder;

[0072] S7. Ultrasonicate the Cu:NiO x nano powder under an ultrasonic probe for 1.5 h to obtain a Cu:NiO x nano aqueous dispersion.

[0073] Provide a solar perovskite battery device, and its manufacturing method includes the following steps: spin-coat the copper-doped nickel oxide nano material aqueous dispersion in the embodiment on an ITO anode layer, then anneal at 120 °C for 30 min to form a hole transport layer; spin-coat a perovskite solution on the hole transport layer as a carrier part to form an absorption layer; spin-coat an isopropanol solution of zinc oxide on the absorption layer, and form an electron transport layer after drying; finally, evaporate and deposit an Au cathode electrode layer and encapsulate to form a perovskite solar battery device.

[0074] Comparative Example 1

[0075] Conventional copper-doped NiO x Preparation includes the following steps:

[0076] S1. At 25 °C, mix 0.3 mol nickel nitrate, 0.006 mol copper nitrate and 1 L of water to obtain a first reaction system;

[0077] S2. Add 0.6 mol of NaOH to the first reaction system, and obtain a Cu:Ni(OH)2 sol dispersion system after reacting for 2 h;

[0078] S3. Centrifuge the above Cu:Ni(OH)2 sol dispersion system, wash it twice with water until the nitrate ions are eluted completely;

[0079] S4. Calcinate S4 at 280 °C for 1 h to obtain black Cu:NiO x calcined body;

[0080] S5. Ultrasonicate the Cu:NiO x nano powder under an ultrasonic probe for 1 h to obtain a Cu:NiO x nano aqueous dispersion.

[0081] Table 1: Comparison of device performances in each example

[0082]

[0083]

[0084] Note: PCE stands for Power Conversion Efficiency, and TGA stands for Thermogravimetric Analysis.

[0085] It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. Aqueous copper-doped NiO x The method for preparing a nano material is characterized in that: The following steps are involved: S1. mixing one or more of alcohol ether, alcohol amine, polyol, polyethylene glycol and a solvent to form a first reaction system; S2. Under a 10-30°C environment, the nickel salt, the copper salt and the first reaction system are mixed to obtain a second reaction system; S3. Add 10%-50% of a base by mass to the second reaction system, control the pH at 8-12, react for 0.2-24h to obtain a Cu:Ni(OH)2 sol dispersion system, add a nickel salt and a base to the obtained Cu:Ni(OH)2 sol dispersion system, control the pH at 8-12, and react for 0.5-12h; S4. Centrifuge the Cu:Ni(OH)2 sol dispersion system and wash it several times until no anions are present; S5. Calcine the Cu:Ni(OH)2 sol of S4 at 200℃-300℃ for 1-24h to obtain black Cu:NiO x calcined body; S6.Cu:NiO x The calcined body was ball milled in a ball mill for 0.5-24h to obtain Cu:NiO x Nano powder; S7.Cu:NiO x The nanopowder was ultrasonicated for 0.1-10h under an ultrasonic probe to obtain Cu:NiO x Nano-aqueous dispersion; Aqueous copper-doped NiO x Copper-doped NiO inside the nanomaterial structure x As the core, there is another layer of NiO outside the core x As shell, NiO x The outer surface of the polymer is an organic ligand, and the organic ligand is one or more of alcohol ether, alcohol amine, polyol, and polyethylene glycol.

2. Aqueous copper-doped NiO according to claim 1 x The method for preparing nanomaterials is characterized by: The alcohol ether described in S1 is a straight-chain alcohol ether with a carbon chain number of 3-5; the alcohol amine is a straight-chain alcohol amine with a carbon chain number of 2-5; the polyol is a glycol with a carbon chain number of 2-6; and the solvent is one of water, methanol and ethanol.

3. Aqueous copper-doped NiO according to claim 2 x The method for preparing nanomaterials is characterized by: The volume ratio of the total volume of alcohol ether, alcohol amine, polyol and polyethylene glycol to the solvent in the first reaction system is: (0.1-0.5):

1.

4. Aqueous copper-doped NiO according to claim 3 x The method for preparing nanomaterials is characterized by: In terms of the amount of substance, the overall feed ratio of the nickel salt and the base in S3 is 1:(0.5-3).

5. Aqueous copper-doped NiO prepared according to the method according to any one of claims 1 to 4 x Nanomaterials, characterized by: Aqueous copper doped NiO x The semiconductor configuration of nanomaterials is type I structure, which means that the bottom of the conduction band and the top of the valence band of one material are both within the bandgap width of another material.

6. Aqueous copper-doped NiO according to claim 5 x Nanomaterials, characterized by: The organic ligand content accounts for 5%-30% of the total weight of the entire nano material. The particle size of the nano material is 3-10nm and the band gap is 3.6eV-4.0eV.

7. Aqueous copper-doped NiO according to claim 6 x Nanomaterials, characterized by: In terms of mass, the copper-doped NiO x The ratio of Ni:Cu in nanomaterials is 1:(0.01~0.5), NiO x The invention comprises nickelous oxide and nickelous oxide, wherein the molar ratio of trivalent nickel to divalent nickel is 0.1-1.

8. A water-based copper-doped NiO as claimed in claim 7 x Application of nanomaterials as hole transport layer materials in perovskite solar cells.

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