Preparation method of strong-polarity tin oxide nano material and product and application of strong-polarity tin oxide nano material

Abstract

The invention belongs to the technical field of solar cells, and relates to a preparation method, a product and application of a strong-polarity tin oxide nano material. A Meerwein reagent is used for carrying out ligand modification on an organic amine and organic acid modified SnO2 nano material to obtain a nano material modified by one or more ligands of tetrafluoroborate BF4 <->, Me3O <-> and Et3O <->, so that the nano material can be dispersed in a strong-polarity organic solvent and then is spin-coated or blade-coated on an ITO / FTO (indium tin oxide / fluorine-doped tin oxide) substrate or a perovskite layer; the obtained tin oxide film has relatively good conductivity and leveling property, excellent film-forming property and relatively good spreadability; meanwhile, the tin oxide organic strong-polarity dispersion liquid has long-term stability in the aspect of storage stability; and the material has excellent light conversion efficiency in the aspect of device performance.

Description

Technical Field

[0001] The invention belongs to the technical field of solar cells and relates to a preparation method of a highly polar tin oxide nano material and a product and application thereof. Background Art

[0002] In perovskite solar cells, for the formal structure, the upper layer of the transparent electrode is the electron transport layer. After the sunlight passes through the transparent electrode, it passes through the electron transport layer and then to the light absorption layer. The conversion efficiency of the formal (nip) structure is higher than that of the trans structure, with higher Voc and Jsc values, but the hysteresis effect is more obvious than that of the trans structure.

[0003] Tin oxide is an important n-type semiconductor material with a band gap energy between 3.6-4.0 eV and an electron mobility of up to 240 cm 2 / V·s, as a commonly used electron transport layer material in formal perovskite solar cells, it has the advantages of being cheap, stable, and easy to prepare. For formal perovskite devices, conventional tin oxide is dispersed in water for spin coating. The introduction of water will cause the upper layer of perovskite to dissociate, affecting the performance and life of the device. For trans devices, tin oxide needs to be spin-coated on the perovskite layer, and conventional tin oxide water dispersion cannot be used, which greatly affects the application of tin oxide in solar cells. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing a highly polar tin oxide nanomaterial, a product thereof and an application thereof, so as to solve the problems existing in the above-mentioned prior art.

[0005] A method for preparing a highly polar tin oxide nanomaterial comprises the following steps:

[0006] S1. Under a 10-30°C environment, organic amine, organic acid and organic solvent are mixed to form a first reaction system;

[0007] S2. The tin oxide nanopowder and the first reaction system are mixed to obtain a second reaction system, and stirred for 0.1-72h, after which methanol or ethanol is added for precipitation and centrifugation to obtain an organic amine or organic acid-modified tin oxide nanomaterial;

[0008] S3. Add the tin oxide nanomaterial obtained in S2 into an organic solvent, stir with Meerwein reagent for 1-7 days, then add a precipitant thereto, precipitate, centrifuge, collect the precipitate, and the obtained precipitate is the highly polar tin oxide nanoparticles.

[0009] S4. Dispersing the highly polar tin oxide nanoparticles into a highly polar organic solvent.

[0010] Furthermore, the organic amine described in S1 is a C4-C18 straight-chain amine; and the organic acid is a C4-C18 straight-chain acid.

[0011] Furthermore, the organic solvent described in S1 is one of dichloromethane, chloroform, toluene, n-hexane, n-heptane and n-octane.

[0012] Furthermore, the volume ratio of each substance in the second reaction system in S2, when the mass of tin oxide is 1g, is (1-10): (1-10): (10-50).

[0013] Furthermore, the Meerwein reagent in S3 is trimethyloxonium tetrafluoroborate or triethyloxonium tetrafluoroborate.

[0014] Furthermore, the precipitant in S3 is acetonitrile or acetone.

[0015] The highly polar tin oxide nanomaterial prepared by any of the above preparation methods, wherein the tin oxide nanoparticles include tin oxide inorganic matter and inorganic ligands and organic ligands on the surface of the tin oxide inorganic matter. The inorganic ligand is tetrafluoroborate BF 4- , the organic ligand is MeO - , EtO - .

[0016] Furthermore, the 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 range is 3.6eV-4.0eV.

[0017] The application of the highly polar tin oxide nanomaterial as described above as an electron transport layer material for perovskite solar cells.

[0018] The beneficial effects of the present invention are as follows:

[0019] The present invention uses Meerwein reagent to perform ligand modification on SnO2 nanomaterials modified by organic amines and organic acids to obtain tetrafluoroborate BF4 - ,Me3O - ,Et3O - One or more ligand-modified nanomaterials can be dispersed in a strongly polar organic solvent and then spin-coated or scraped on an ITO / FTO substrate or a perovskite layer. The resulting tin oxide film has good conductivity, leveling, excellent film-forming properties, and good spreadability. At the same time, the tin oxide organic strongly polar dispersion has not only long-term stability in storage stability, but also excellent light conversion efficiency in device performance.

[0020] The present invention introduces anhydrous water during the synthesis process, and secondly, the tetrafluoroborate on the surface of tin oxide makes tin oxide have a good dispersing and dissolving effect in a strong polar solvent, which is suitable for spin coating and more conducive to scraping, so that perovskite solar cells can be industrialized and mass-produced. 4- ) has a short chain structure and has an inherent advantage in conductivity compared to organic ligands; the particle size of 3-10nm is conducive to the smoothness of the SnO2 film surface and reduces the interface barrier. The introduction of organic acids and organic amines makes it easy for SnO2 nanomaterials to be dispersed in organic solvents and react better with Me3OBF4. SnO2 and Me3OBF4 alone cannot react or cannot achieve the dispersion effect. The entire reaction is carried out at room temperature, which is green, environmentally friendly and pollution-free, avoiding the occurrence of danger. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the TEM image of the highly polar SnO2 nanoparticles prepared in the present invention.

[0022] Figure 2 This is the XRD diagram of the highly polar SnO2 nanoparticles prepared in the present invention.

[0023] Figure 3 This is the UV-visible absorption diagram of the highly polar SnO2 nanoparticles prepared in the present invention.

[0024] Figure 4 This is the thermogravimetric analysis diagram of the highly polar SnO2 nanoparticles prepared in the present invention. DETAILED DESCRIPTION

[0025] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] The present invention provides a method for preparing highly polar SnO2 nanoparticles, comprising the following steps:

[0027] S1. Under a 10-30°C environment, organic amine, organic acid and organic solvent are mixed to form a first reaction system;

[0028] S2. The tin oxide nanopowder and the first reaction system are mixed to obtain a second reaction system, and stirred for 0.1-72h, after which methanol or ethanol is added for precipitation and centrifugation to obtain an organic amine or organic acid-modified tin oxide nanomaterial;

[0029] S3. Add the tin oxide nanomaterial obtained in S2 to an organic solvent, stir with Meerwein reagent for 1-7 days, then add a precipitant thereto, precipitate, centrifuge, and collect the precipitate. The precipitate obtained is the highly polar tin oxide nanomaterial.

[0030] S4. The highly polar tin oxide nanomaterial can be dispersed in a highly polar organic solvent.

[0031] The highly polar tin oxide nanomaterial can be dissolved in highly polar organic solvents, such as DMF, DMSO, NMP, MeOH, EtOH, acetonitrile, etc.;

[0032] The organic amine described in S1 above is a C4-C18 straight-chain amine, for example, one of n-butylamine, n-hexylamine, n-dodecylamine and oleylamine.

[0033] The organic acid described in S1 above is a C4-C18 straight-chain acid, for example, one of n-butyric acid, n-hexanoic acid, n-dodecanoic acid and oleic acid.

[0034] The organic solvent described in S1 above is one of dichloromethane, chloroform, toluene, n-hexane, n-heptane and n-octane.

[0035] The SnO2 nanopowder described in S2 above has a particle size of 3-10 nm;

[0036] The SnO2 nanopowder described in S2 above has a band gap of 3.6-4.0 eV;

[0037] The SnO2 nanopowder synthesis method described in S2 above is not limited to sol-gel, hydrothermal method, and high temperature decomposition method;

[0038] The synthesis process in the S2 system is not limited to stirring reaction, and can be one of microwave reaction, stirring reaction, ultrasonic reaction, and hydrothermal reaction.

[0039] Embodiment 1

[0040] S1. At room temperature, 10 ml of n-butylamine, 1 ml of n-butyric acid and 100 ml of n-heptane were mixed to form a first reaction system;

[0041] S2. 0.5 g of 5 nm SnO2 nanopowder was mixed with the first reaction system to obtain a second reaction system, and stirred for 24 h, after which 200 ml of methanol was added for precipitation and centrifuged at 4000 rpm to obtain butylamine, butyric acid-modified SnO2 nanomaterials;

[0042] S3. The SnO2 nanomaterial obtained in S2 was added with 50 ml of acetonitrile and 1 g of trimethyloxonium tetrafluoroborate and stirred for 5 days, and then 50 ml of acetone was added thereto and centrifuged at 5000 rpm. The resulting precipitate was a highly polar SnO2 nanomaterial.

[0043] S4. Disperse the above-mentioned highly polar SnO2 nanomaterial in 50 ml of DMF solution to prepare a 2.5 wt% SnO2DMF dispersion.

[0044] Embodiment 2

[0045] S1. At room temperature, 10 ml of n-octylamine, 1 ml of n-octanoic acid and 100 ml of n-octane were mixed to form a first reaction system;

[0046] S2. 0.5 g of 5 nm SnO2 nanopowder was mixed with the first reaction system to obtain a second reaction system, and subjected to ultrasound for 3 h, after which 200 ml of ethanol was added for precipitation and centrifuged at 500 rpm to obtain n-octylamine, n-octanoic acid-modified SnO2 nanomaterials;

[0047] S3. The SnO2 nanomaterial obtained in S2 was added with 50 ml of acetonitrile and 1 g of triethyloxonium tetrafluoroborate and stirred for 5 days, and then 50 ml of acetone was added thereto and centrifuged at 5000 rpm. The resulting precipitate was a highly polar SnO2 nanomaterial.

[0048] S4. Disperse the above-mentioned highly polar SnO2 nanomaterial in 50 ml of DMSO solution to prepare a 3 wt% SnO2DMSO dispersion.

[0049] Embodiment 3

[0050] S1. At room temperature, 10 ml of oleylamine, 2 ml of oleic acid and 100 ml of n-hexane were mixed to form a first reaction system;

[0051] S2. 0.6 g of 7 nm SnO2 nanopowder was mixed with the first reaction system to obtain a second reaction system, and the reaction was heated in a microwave oven for 1 h, after which 300 ml of methanol was added for precipitation and centrifuged at 5000 rpm to obtain oleylamine and oleic acid-modified SnO2 nanomaterials;

[0052] S3. The SnO2 nanomaterial obtained in S2 was added to 60 ml of n-hexane, 2.5 g of triethyloxonium tetrafluoroborate was added and stirred for 6 days, and then 50 ml of acetone was added thereto, precipitated, and centrifuged at 4000 rpm. The resulting precipitate was a highly polar SnO2 nanomaterial;

[0053] S4. Disperse the above-mentioned highly polar SnO2 nanomaterial in 50 ml of NMP solution to prepare a 3 wt% SnO22DMSO dispersion.

[0054] A solar perovskite cell device, the manufacturing method of which comprises the following steps: spin coating the above-mentioned 2.5wt% SnO2 nanomaterial DMF dispersion on the IT0 anode layer, and then annealing at 120°C for 30 minutes to form an electron transport layer; spin coating a perovskite solution on the hole transport layer as a carrier to form an absorption layer; spin coating an isopropanol solution of zinc oxide on the absorption layer, and forming an electron transport layer after drying; and finally evaporating an Au cathode electrode layer and encapsulating to form a formal perovskite solar cell device.

[0055] A solar perovskite cell device, the manufacturing method of which comprises the following steps: spin coating a NiOx aqueous dispersion on an IT0 anode layer, and then annealing at 150° C. for 30 min to form a hole transport layer; spin coating a perovskite solution on the hole transport layer as a carrier to form an absorption layer; spin coating a 3wt% SnO2 DMSO dispersion in Example 2 on the absorption layer, and forming an electron transport layer after drying; and finally evaporating an Au cathode electrode layer and encapsulating to form an inverted perovskite solar cell device.

[0056] The device performance parameters of the SnO2 dispersion in the above embodiment are shown in Table 1

[0057]

[0058]

[0059] The above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention.

Claims

1. A method for preparing a highly polar tin oxide nanomaterial, characterized in that: The following steps are involved: S1. Under a 10-30°C environment, organic amine, organic acid and organic solvent are mixed to form a first reaction system; S2. The tin oxide nanopowder and the first reaction system are mixed to obtain a second reaction system, and stirred for 0.1-72h, after which methanol or ethanol is added for precipitation and centrifugation to obtain an organic amine or organic acid-modified tin oxide nanomaterial; S3. Add the tin oxide nanomaterial obtained in S2 into an organic solvent, stir with Meerwein reagent for 1-7 days, then add a precipitant thereto, precipitate, centrifuge, collect the precipitate, and the obtained precipitate is the highly polar tin oxide nanoparticles. S4. Dispersing the highly polar tin oxide nanoparticles into a highly polar organic solvent.

2. The method for preparing the highly polar tin oxide nanomaterial according to claim 1, characterized in that: The organic amine described in S1 is a C4-C18 straight-chain amine; the organic acid is a C4-C18 straight-chain acid.

3. The method for preparing the highly polar tin oxide nanomaterial according to claim 1, characterized in that: The organic solvent described in S1 is one of dichloromethane, chloroform, toluene, n-hexane, n-heptane and n-octane.

4. The method for preparing the highly polar tin oxide nanomaterial according to claim 1, characterized in that: The ratio of each substance in the second reaction system in S2 is (1-10): (1-10): (10-50) in volume when the mass of tin oxide is 1g.

5. The method for preparing the highly polar tin oxide nanomaterial according to claim 1, characterized in that: The Meerwein reagent in S3 is trimethyloxonium tetrafluoroborate or triethyloxonium tetrafluoroborate.

6. The method for preparing highly polar tin oxide nanoparticles according to claim 1, characterized in that: The precipitant in S3 is acetonitrile or acetone.

7. A highly polar tin oxide nanomaterial prepared by the preparation method according to any one of claims 1 to 6, wherein the tin oxide nanoparticles comprise tin oxide inorganic matter and inorganic ligands on the surface of the tin oxide inorganic matter, and organic ligands. The inorganic ligand is tetrafluoroborate BF4 - , the organic ligand is MeO - , EtO - .

8. The highly polar tin oxide nanomaterial according to claim 7, characterized in that: The 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 range is 3.6eV-4.0eV.

9. Use of the highly polar tin oxide nanomaterial as claimed in claim 7 as an electron transport layer material for a perovskite solar cell.

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