Method for inhibiting agglomeration of NiOx dispersion liquid

Abstract

The invention belongs to the technical field of perovskite solar cell material preparation, and particularly relates to a method for inhibiting agglomeration of NiOx dispersion liquid. According to the method, the SnO2 nanoparticles are directly adopted as the additive, operation is convenient, no purification step is needed, and the stable NiOx dispersion liquid can be obtained. The NiOx dispersion liquid prepared by the preparation method disclosed by the invention can be used for effectively inhibiting gathering and providing a longer-time processing window; meanwhile, the NiOx film prepared by using the NiOx dispersion liquid has higher conductivity. Other organic molecules do not need to be introduced into the NiOx dispersion liquid to coordinate with NiOx, so that subsequent SAM molecule attachment is facilitated; and a basis is provided for a high-efficiency perovskite solar cell.

Description

Technical Field

[0001] This invention belongs to the technical field of perovskite solar cell materials, specifically relating to a method for suppressing NiO. x Methods for preventing dispersion aggregation. Background Technology

[0002] NiO x As a typical p-type semiconductor material, NiO is widely used in the fabrication of hole transport layers in optoelectronic devices such as perovskite solar cells and photodetectors due to its excellent hole transport performance, good optical transparency, and chemical stability. During device fabrication, NiO... x NiO is typically formed into a film in the form of a dispersion through methods such as spin coating and spraying. Therefore, the stability of the dispersion directly determines the film quality. x The uniformity and density of the thin film and the final performance of the device.

[0003] However, NiO x Nanoparticles possess a large specific surface area and high surface energy, making them highly susceptible to aggregation in dispersions due to interactions such as van der Waals forces and hydrogen bonds. Aggregated NiO x Nanoparticles can cause instability in dispersion systems, leading to problems such as precipitation and stratification, which in turn affects the subsequent preparation of NiO. x Increased surface roughness and the presence of pores in the thin film severely reduce hole transport efficiency, leading to a decrease in the photoelectric conversion efficiency and long-term stability of perovskite solar cells.

[0004] To suppress NiO x To address dispersion agglomeration, current techniques often employ methods such as optimizing ultrasonic parameters, adding surfactants (e.g., oleylamine and polyfunctional imidazole tetrafluoroborate), or adjusting the pH of the dispersion. However, these methods have significant limitations: simply optimizing ultrasonic parameters only achieves short-term dispersion, resulting in poor long-term stability; traditional surfactants tend to remain in the film, affecting NiO. x The intrinsic conductivity of NiO and its interfacial contact with subsequent functional layers; adjusting the pH value easily changes the properties of NiO. x Its chemical properties are not suitable for pH-sensitive optoelectronic device precursor systems. Summary of the Invention

[0005] For existing methods to suppress NiO x The dispersion agglomeration method suffers from poor long-term stability, easy residue of impurities affecting device performance, or alteration of NiO. x To address the shortcomings in chemical properties, this invention provides a highly efficient, stable method that does not affect NiO. x Suppression of intrinsic properties NiO x Methods for preventing dispersion aggregation.

[0006] This invention involves applying NiOx Introducing trace amounts of SnO2 into the dispersion to stabilize NiO x Nanoparticles; utilizing SnO2 and NiO x Electrostatic interactions between them change NiO x The charge distribution on the surface of nanoparticles promotes the accumulation of positive charges, thereby generating stronger electrostatic repulsion between nanoparticles and effectively inhibiting their aggregation. Simultaneously, SnO2 and NiO... x The significant difference in lattice constants makes co-aggregation physically difficult, and this modification process does not require the introduction of organic ligands, thus preserving the properties of NiO. x Its intrinsic properties.

[0007] The first objective of this invention is to provide a method for suppressing NiO x A method for preventing dispersion aggregation includes the following steps: NiO x The powder is dispersed in a solvent, then SnO2 is added and stirred to mix, so that NiO... x The accumulation of positive charge on the surface of nanoparticles yields NiO. x Dispersion; NiO x The concentration of SnO2 in the dispersion is 0.1 mg / mL to 1 mg / mL.

[0008] It should be noted that the present invention achieves this by applying NiO... x Adding trace amounts of SnO2 nanoparticles to the dispersion to stabilize NiO x Nanoparticles. The lattice constant of SnO2 (a=b=4.73Å, c=3.187Å) and NiO. x The difference between SnO2 and NiO (a=b=c=4.18Å) is significant (11.5%–33.2%). x Nanoparticles are less prone to aggregation upon collision. Simultaneously, under the influence of electrostatic forces, SnO2 reacts with surrounding NiO. x The nanoparticles repeatedly undergo elastic collisions, causing changes in NiO through mirror charge. x The charge distribution on the surface of nanoparticles promotes NiO x The accumulation of positive charges on the surface of nanoparticles. This invention utilizes SnO2 nanoparticles modified with NiO. x The nanoparticles exhibit significantly enhanced resistance to aggregation and an increased number of surface hydroxyl groups, providing a foundation for uniform and complete coverage of the subsequent SAM layer.

[0009] Preferably, the amount of SnO2 added is NiO. x The concentration of SnO2 should be 1% to 10% of the powder mass. Within this range, the agglomeration inhibition effect can be guaranteed while avoiding excessive SnO2.

[0010] Preferably, NiOx NiO in dispersion x The concentration is 10 mg / mL to 15 mg / mL. NiO x Too low a concentration of NiO will lead to x Incomplete film coverage resulted in pores; NiO x Excessive concentration of NiO will lead to x The aggregation of the dispersion is detrimental to the subsequent NiO production. x Thin film preparation.

[0011] Preferably, NiO x The specific preparation method of the dispersion is as follows: NiO x The powder is dispersed in a solvent and ultrasonically mixed to make NiO x The powder is evenly dispersed to obtain basic NiO. x Dispersion; base NiO x The dispersion was stirred and mixed with SnO2 hydrocolloid to make NiO x The accumulation of positive charge on the surface of nanoparticles yields NiO. x Dispersion.

[0012] Preferably, the SnO2 particle size in the SnO2 hydrocolloid is 5nm to 20nm. Excessively large particle size will affect the NiO... x Thin film preparation.

[0013] Preferably, NiO x The powder has a cubic phase crystal structure.

[0014] Preferably, the mixing method is as follows: Stirring and mixing at 300 rpm to 600 rpm for 5 to 10 minutes at 25℃ to 35℃. This allows SnO2 and NiO to mix. x Stable NiO is obtained after thorough mixing of nanoparticles. x Dispersion.

[0015] Preferably, the ultrasonic mixing method is as follows: ultrasonic treatment at a power of 80W to 120W for 5 to 10 minutes, so that NiO... x The powder was initially dispersed evenly to obtain basic NiO. x Dispersion.

[0016] Preferably, the solvent is water.

[0017] This invention provides a NiO x Dispersion, the NiO x The dispersion is made of NiO x It consists of nanoparticles, water, and SnO2.

[0018] Preferably, NiO xNiO in dispersion x The average particle size of the nanoparticles is 15 nm to 20 nm.

[0019] This invention provides a perovskite solar cell, comprising a conductive substrate and, sequentially stacked on the conductive substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and an electrode; the hole transport layer is made of NiO. x The dispersion was prepared by film formation and annealing.

[0020] Preferably, the thickness of the hole transport layer is 20nm to 50nm.

[0021] Preferably, the perovskite light-absorbing layer is prepared by forming a film from a perovskite precursor, the chemical formula of which is FA. 0.8 MA 0.2 PbI3. Where FA represents formamidinium cation and MA represents methylammonium ion.

[0022] Compared with the prior art, the present invention has the following technical effects: This invention involves applying NiO x Introducing trace amounts of SnO2 into the dispersion to stabilize NiO x Nanoparticles; utilizing SnO2 and NiO x Electrostatic interactions between them change NiO x The charge distribution on the surface of nanoparticles promotes the accumulation of positive charges, thereby generating stronger electrostatic repulsion between nanoparticles and effectively inhibiting their aggregation. Simultaneously, SnO2 and NiO... x The significant difference in lattice constants makes co-aggregation physically difficult, and this modification process does not require the introduction of organic ligands, thus preserving the properties of NiO. x Its intrinsic properties.

[0023] The NiO of the present invention x Dispersion relative to other NiO x For dispersions, this method can effectively suppress aggregation and provide a longer processing window; simultaneously, NiO prepared using this dispersion... x The thin film exhibits higher conductivity; and the dispersion does not require the introduction of other organic molecules with NiO. x Coordination facilitates the subsequent attachment of SAM molecules. Attached Figure Description

[0024] Figure 1 NiO from Examples 1 to 5 and Comparative Example 1 x Zeta potential graph of the dispersion.

[0025] Figure 2 NiO for Example 1 and Comparative Example 1 xDynamic light scattering patterns of the dispersion before and after aging. (a) shows the NiO dispersion from Comparative Example 1. x (a) Dynamic light scattering diagrams of the dispersion before and after aging; (b) NiO from Example 1. x Dynamic light scattering diagrams of the dispersion before and after aging.

[0026] Figure 3 NiO in Example 1 and Comparative Example 1 x NiO dispersion x Transmission electron microscope images of nanoparticles. Among them, (a) shows NiO from Example 1. x NiO dispersion x (a) Transmission electron microscope image of nanoparticles; (b) NiO in Comparative Example 1 x NiO dispersion x Transmission electron microscope image of nanoparticles.

[0027] Figure 4 For the application of NiO in Example 1 and Comparative Example 1 x Atomic force microscopy images of the thin film. (a) shows NiO film obtained using Comparative Example 1. x (a) Atomic force microscopy image of the thin film; (b) NiO from Application Example 1 x Atomic force microscope image of a thin film.

[0028] Figure 5 NiO prepared for application Example 1 and Comparative Example 1 x XPS spectra of the thin films. (a) shows the NiO film prepared using Comparative Example 1. x XPS spectra of the thin film; (b) NiO prepared in Application Example 1 x XPS spectra of the thin film.

[0029] Figure 6 NiO prepared for application Example 1 and Comparative Example 1 x The electrical conductivity of the thin film. Detailed Implementation

[0030] To enable those skilled in the art to better understand and implement the technical solutions of the present invention, the present invention will be further described below in conjunction with specific embodiments and accompanying drawings.

[0031] Unless otherwise specified, all reagents used in this invention are commercially available, and all methods used are conventional techniques in the art.

[0032] It should be noted that the NiO used in the following embodiments x The powder has a purity of 99.9% and a particle size of 5 nm.

[0033] In a specific embodiment of the present invention, NiO is used. x The powder is dispersed in a solvent and ultrasonically mixed to make NiO x The powder was initially dispersed evenly to obtain basic NiO. x Dispersion; base NiO x The dispersion and SnO2 hydrocolloid were mixed by stirring to obtain NiO. x Dispersion. This requires diluting the SnO2 hydrocolloid 50 to 500 times before mixing it with the base NiO. x The dispersion was mixed to obtain NiO. x Dispersion; NiO x The concentration of SnO2 in the dispersion is 0.1 mg / mL to 1 mg / mL.

[0034] Example 1 A method for fabricating a perovskite solar cell includes the following steps: Weigh out 15mg of NiO x Add the powder to 1 mL of deionized water, place it in an ultrasonic cleaner, set the ultrasonic power to 100 W, and the ultrasonic time to 5 min to ensure NiO x The powder was initially and evenly dispersed to obtain a basic NiO with a concentration of 15 mg / mL. x Dispersion.

[0035] After diluting the SnO2 hydrocolloid with a mass fraction of 20%, it was mixed with the base NiO. x The dispersions were mixed at a volume ratio of 4:6, and the stirring speed was set to 400 rpm for 5 minutes to obtain stable NiO. x Dispersion. The amount of SnO2 added was 0.5 mg / mL.

[0036] NiO x Stability verification of the dispersion: Prepared NiO x The dispersion was allowed to stand at a constant temperature of 25℃ for 72 hours, and NiO was observed. x The dispersion remained homogeneous throughout, without any precipitation or stratification. Dynamic light scattering analysis results showed that at 0 h, NiO... x The average particle size of the nanoparticles is 15 nm, and after 72 hours, NiO x The average particle size of the nanoparticles is 25 nm. The Zeta potential test result is 45.4 mV, indicating that NiO... x The dispersion exhibits excellent stability.

[0037] Example 2 A method for fabricating a perovskite solar cell includes the following steps: The difference from Example 1 is that SnO2 is in stable NiOx The addition amount in the dispersion was 0.1 mg / mL.

[0038] Weigh out 15mg of NiO x Add the powder to 1 mL of deionized water, place it in an ultrasonic cleaner, set the ultrasonic power to 100 W, and the ultrasonic time to 5 min to ensure NiO x The powder was initially and evenly dispersed to obtain a basic NiO with a concentration of 15 mg / mL. x Dispersion.

[0039] After diluting the SnO2 hydrocolloid with a mass fraction of 20%, it was mixed with the base NiO. x The dispersions were mixed at a volume ratio of 4:6 and stirred at 400 rpm for 5 minutes to obtain stable NiO. x Dispersion. SnO2 is contained in stable NiO. x The addition amount in the dispersion was 0.1 mg / mL.

[0040] NiO x Stability verification of the dispersion: Prepared NiO x The dispersion was allowed to stand at a constant temperature of 25℃ for 72 hours, and NiO was observed. x The dispersion remained homogeneous throughout, without any precipitation or stratification. The Zeta potential test result was 37.5 mV, indicating that NiO... x The stability of the dispersion is satisfactory.

[0041] Example 3 A method for fabricating a perovskite solar cell includes the following steps: The difference from Example 1 is that SnO2 is in stable NiO x The addition amount in the dispersion was 0.25 mg / mL.

[0042] Weigh out 15mg of NiO x Add the powder to 1 mL of deionized water, place it in an ultrasonic cleaner, set the ultrasonic power to 100 W, and the ultrasonic time to 5 min to ensure NiO x The powder was initially and evenly dispersed to obtain a basic NiO with a concentration of 15 mg / mL. x Dispersion.

[0043] After diluting the SnO2 hydrocolloid with a mass fraction of 20%, it was mixed with the base NiO. x The dispersions were mixed at a volume ratio of 4:6, and the stirring speed was set to 400 rpm for 5 minutes to obtain stable NiO. x Dispersion. SnO2 is contained in stable NiO. x The addition amount in the dispersion was 0.25 mg / mL.

[0044] NiO x Stability verification of the dispersion: Prepared NiO x The dispersion was allowed to stand at a constant temperature of 25℃ for 72 hours, and NiO was observed. x The dispersion remained homogeneous throughout, without any precipitation or stratification. The Zeta potential test result was 40.9 mV, indicating that NiO... x The stability of the dispersion is satisfactory.

[0045] Example 4 A method for fabricating a perovskite solar cell includes the following steps: The difference from Example 1 is that SnO2 is in stable NiO x The addition amount in the dispersion was 0.8 mg / mL.

[0046] Weigh out 15mg of NiO x Add the powder to 1 mL of deionized water, place it in an ultrasonic cleaner, set the ultrasonic power to 100 W, and the ultrasonic time to 5 min to ensure NiO x The powder was initially and evenly dispersed to obtain a basic NiO with a concentration of 15 mg / mL. x Dispersion.

[0047] After diluting the SnO2 hydrocolloid with a mass fraction of 20%, it was mixed with the base NiO. x The dispersions were mixed at a volume ratio of 4:6, and the stirring speed was set to 400 rpm for 5 minutes to obtain stable NiO. x Dispersion. SnO2 is contained in stable NiO. x The addition amount in the dispersion was 0.8 mg / mL.

[0048] NiO x Stability verification of the dispersion: Prepared NiO x The dispersion was allowed to stand at a constant temperature of 25℃ for 72 hours, and NiO was observed. x The dispersion remained homogeneous throughout, without any precipitation or stratification. The Zeta potential test result was 39.3 mV, indicating that NiO... x The stability of the dispersion is satisfactory.

[0049] Example 5 A method for fabricating a perovskite solar cell includes the following steps: The difference from Example 1 is that SnO2 is in stable NiO x The addition amount in the dispersion is 1 mg / mL.

[0050] Weigh out 15mg of NiOx Add the powder to 1 mL of deionized water, place it in an ultrasonic cleaner, set the ultrasonic power to 100 W, and the ultrasonic time to 5 min to ensure NiO x The powder was initially and evenly dispersed to obtain a basic NiO with a concentration of 15 mg / mL. x Dispersion.

[0051] The SnO2 hydrocolloid with a mass fraction of 20% was diluted 50 times and then mixed with the base NiO. x The dispersions were mixed at a volume ratio of 4:6, and the stirring speed was set to 400 rpm for 5 minutes to obtain stable NiO. x Dispersion. SnO2 is contained in stable NiO. x The addition amount in the dispersion is 1 mg / mL.

[0052] NiO x Stability verification of the dispersion: Prepared NiO x The dispersion was allowed to stand at a constant temperature of 25℃ for 72 hours, and NiO was observed. x The dispersion remained homogeneous throughout, without any precipitation or stratification. The Zeta potential test result was 30.1 mV, indicating that NiO... x The stability of the dispersion decreased.

[0053] Comparative Example 1 A method for fabricating a perovskite solar cell includes the following steps: The difference from Example 1 is that SnO2 was not added.

[0054] Weigh out 15mg of NiO x Add the powder to 1 mL of deionized water, place it in an ultrasonic cleaner, set the ultrasonic power to 100 W, and the ultrasonic time to 5 min to ensure NiO x The powder was initially and evenly dispersed to obtain NiO with a concentration of 15 mg / mL. x Dispersion.

[0055] NiO x Stability verification of the dispersion: Prepared NiO x The dispersion was allowed to stand at a constant temperature of 25℃ for 72 hours, and NiO was observed. x The dispersion exhibited clear stratification, with a large amount of precipitate in the lower layer. DLS test results showed that NiO at 0h... x The average particle size of the nanoparticles is 30 nm, and after 72 h, NiO x The average particle size of the nanoparticles is 50 nm. The Zeta potential test result is 36.2 mV, indicating that the basic NiO... x The dispersion has extremely poor stability.

[0056] Application Example 1 The ITO glass was ultrasonically cleaned with acetone, ethanol and deionized water for 15 minutes in sequence, and then dried with nitrogen.

[0057] The NiO prepared in Example 1 was transported using a micropipette. x The dispersion was drop-coated onto a cleaned ITO glass surface and spin-coated at 3500 rpm for 30 s, followed by annealing at 120 °C for 20 min to obtain NiO. x Thin film, denoted as S-NiO x , as a hole transport layer.

[0058] A concentration of 0.2 mg / mL -1 MEO-4PACz ethanol solution was spin-coated onto NiO at 4000 rpm. x NiO was obtained by annealing the thin film at 100°C for 10 minutes. x / MEO-4PACz hole transport layer.

[0059] 172 mg of FAI and 461 mg of PbI₂ were dissolved in 800 μL of 2-mercaptoethanol to obtain a 1.25 mM FAPbI₃ solution. 159 mg of MAI and 461 mg of PbI₂ were dissolved in 800 μL of 2-mercaptoethanol to obtain a 1.25 mM MAPbI₃ solution. 67.5 mg of MACl was dissolved in 1 mL of 2-mercaptoethanol to obtain a 1 mM MACl solution. 80.5 mg of FACl was dissolved in 1 mL of 2-mercaptoethanol to obtain a 1 mM FACl solution.

[0060] Mix 90 μL of FAPbI3 solution with 10 μL of MAPbI3 solution, then add 12 μL of MACl solution, 2 μL of FACl solution and 7 μL of N-methylpyrrolidone as additives, and stir thoroughly until a clear precursor solution is obtained.

[0061] The blade coating speed is set to 6 mm / s. -1 The distance between the scraper and the substrate was 0.18 mm, and the pressure of the nitrogen air knife was 0.2 MPa. NiO was then... x The substrate with the / MEO-4PACz hole transport layer is adsorbed onto the moving platform of a blade coater, and 4 μL of precursor solution is uniformly added along the edge of the substrate. The moving blade spreads the precursor solution evenly onto the NiO substrate. x The membrane was then deposited onto a MEO-4PACz hole transport layer and blown with nitrogen to form a semi-wet film. The semi-wet film was then rapidly transferred to a hot plate at 100°C and annealed for 15 minutes to obtain a perovskite film.

[0062] PC 61 BM chlorobenzene solution (20 mg·mL) -1 ) and BCP ethanol solution (0.5 mg·mL) -1 The coating was spin-coated onto the top of the perovskite film at speeds of 1500 rpm and 3000 rpm, respectively. Finally, at 6 × 10⁻⁶ rpm... -4 Under a vacuum pressure of Pa, 100 nm Ag electrodes are evaporated to complete the assembly of perovskite solar cells.

[0063] Under AM 1.5G simulated sunlight, the photoelectric conversion efficiency (PCE) of the perovskite solar cell was tested using a photovoltaic performance tester. The test results showed that its PCE was 23.5%, its open-circuit voltage (Voc) was 1.18V, and its short-circuit current density (Jsc) was 24.2mA / cm². 2 The fill factor (FF) is 0.82.

[0064] Application Example 2 The fabrication method of the perovskite solar cell in Application Example 1 is the same, except that NiO from Example 2 is used. x NiO preparation from dispersion x Thin films are used as hole transport layers to assemble perovskite solar cells.

[0065] Under AM 1.5G simulated sunlight, the photoelectric conversion efficiency of the perovskite solar cell was tested using a photovoltaic performance tester. The test results showed that PCE=20.5%, Voc=1.10V, and Jsc=23.8mA / cm². 2 , FF=0.78.

[0066] Application Example 3 The fabrication method of the perovskite solar cell in Application Example 1 is the same, except that NiO from Example 3 is used. x NiO preparation from dispersion x Thin films are used as hole transport layers to assemble perovskite solar cells.

[0067] Under AM 1.5G simulated sunlight, the photoelectric conversion efficiency of the perovskite solar cell was tested using a photovoltaic performance tester. The test results showed that PCE=22.3%, Voc=1.14V, and Jsc=24.9mA / cm². 2 , FF=0.78.

[0068] Application Example 4 The fabrication method of the perovskite solar cell in Application Example 1 is the same, except that NiO from Example 4 is used. x NiO preparation from dispersion x Thin films are used as hole transport layers to assemble perovskite solar cells.

[0069] Under AM 1.5G simulated sunlight, the photoelectric conversion efficiency of the perovskite solar cell was tested using a photovoltaic performance tester. The test results showed that PCE=21.5%, Voc=1.15V, and Jsc=24.32mA / cm². 2 , FF=0.79.

[0070] Application Example 5 The fabrication method of the perovskite solar cell in Application Example 1 is the same, except that NiO from Example 5 is used. x NiO preparation from dispersion x Thin films are used as hole transport layers to assemble perovskite solar cells.

[0071] Under AM 1.5G simulated sunlight, the photoelectric conversion efficiency of the perovskite solar cell was tested using a photovoltaic performance tester. The test results showed 19.1%, Voc=1.14V, and Jsc=23.5mA / cm². 2 , FF=0.71.

[0072] Application Comparative Example 1 The fabrication method of the perovskite solar cell in Application Example 1 is the same, except that NiO from Comparative Example 1 is used. x NiO preparation from dispersion x Thin films are used as hole transport layers to assemble perovskite solar cells.

[0073] like Figure 4 As shown in (a), NiO x The surface of the hole transport layer is uneven, with an RMS of 6.5 nm and a large number of pores.

[0074] Under AM 1.5G simulated sunlight, the photoelectric conversion efficiency of the perovskite solar cell was tested using a photovoltaic performance tester. The test results showed that PCE=19.4%, Voc=1.13V, and Jsc=24.15mA / cm². 2 , FF=0.72.

[0075] Test 1: NiO at 25℃ was tested using a Zeta potentiometer. x The zeta potential of the dispersion; the higher the absolute value of the zeta potential, the better the NiO content. x The stronger the stability of the dispersion.

[0076] like Figure 1 As shown, when the amount of SnO2 added is <0.5 mg / mL, NiO x The properties of the dispersion are determined by NiO x Dominant; NiO modified with SnO2x The zeta potential of the nanoparticles was significantly increased, from the initial 36.2 mV to 45.4 mV. When the SnO2 addition amount was 0.5 mg / mL, the NiO... x The zeta potential of the dispersion reached a maximum of 45.4 mV. When the amount of SnO2 added was further increased, the NiO... x The zeta potential of the dispersion begins to decrease, indicating that the stability of the system is gradually decreasing.

[0077] Test 2: Prepared NiO x The dispersion was placed in a constant temperature environment of 25℃ and NiO was observed at 0 days and 72 hours. x Whether precipitation or stratification occurs in the dispersion; and simultaneously, using a dynamic light scattering instrument to test NiO at different time points. x Average particle size.

[0078] like Figure 2 As shown, the introduction of SnO2 makes NiO x The statistical average size of the nanoparticles decreased from 25 nm to 15 nm, and the particle size distribution became more concentrated. This indicates that SnO2 nanoparticles do not react with NiO. x Nanoparticles aggregate. Simultaneously, SnO2 nanocrystals affect NiO. x The self-aggregation of nanoparticles exhibits sustained inhibitory capabilities. Furthermore, it can be seen that after 72 hours of aging, the NiO in Comparative Example 1... x NiO in solution x The average size of the nanoparticles increased from 25 nm to 45 nm, an increase of 80%, and significant aggregation occurred, which is consistent with Zeta's experimental results. After aging, the NiO in Example 1... x The particle size distribution of the nanoparticles remains almost constant, consistently around 15 nm.

[0079] Test 3: like Figure 3 As shown in the TEM image, the NiO in Example 1 can be seen... x The nanoparticles were uniformly dispersed and did not aggregate; in Comparative Example 1, NiO... x The nanoparticles showed significant aggregation.

[0080] Test 4: NiO was tested using atomic force microscopy. x The surface roughness Ra of the thin film was tested within a range of 5 μm × 5 μm.

[0081] like Figure 4 As shown, the NiO prepared in Example 1 is applied. xThe film has a surface roughness RMS of 6.5 nm, exhibiting a uniform and dense surface without obvious pores or protrusions. This is in contrast to the NiO film used in Comparative Example 1. x Thin film, NiO prepared using Example 1 x The surface roughness of the film was significantly reduced, with RMS decreasing from 6.5 nm to 3.32 nm.

[0082] Test 5: NiO was tested using X-ray photoelectron spectroscopy. x Ni in thin films 3+ with Ni 2+ The proportion of content.

[0083] like Figure 5 As shown, NiO modified with SnO2 x Ni in thin films 3+ with Ni 2+ The proportion increased from 2.36 to 3.20, NiO x The conductivity of the thin film is significantly improved. This is due to the SnO2 nanoparticle-reinforced NiO2 film. x The number of positive charges on the surface of nanoparticles can not only prevent NiO x The aggregation of nanoparticles simultaneously improves Ni 3+ The content of.

[0084] Test 6: NiO was tested using a four-probe tester. x Room temperature conductivity of the thin film.

[0085] like Figure 6 As shown, NiO from Comparative Example 1 is applied. x The conductivity of the thin film is 1.16 × 10⁻⁶. -3 S / m, NiO from Example 1 x The conductivity of the thin film is 1.51 × 10⁻⁶. -3 S / m. Compared to NiO using Comparative Example 1. x Thin film, using NiO from Example 1 x The conductivity of the thin film is significantly improved, and it possesses excellent basic hole transport properties.

[0086] It should be noted that when numerical ranges are involved in this invention, it should be understood that the two endpoints of each numerical range, as well as any value between the two endpoints, can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described in this invention to avoid redundancy. Although preferred embodiments of this invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments, and all such changes and modifications fall within the scope of this invention.

[0087] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. If these modifications and variations fall within the scope of equivalents of this invention, then this invention also intends to include these modifications and variations.

Claims

1. A method for inhibiting NiO x The method for dispersion aggregation is characterized by, Includes the following steps: NiO x The powder is dispersed in a solvent, then SnO2 is added and stirred to mix, so that NiO... x The accumulation of positive charge on the surface of nanoparticles yields NiO. x Dispersion; NiO x The concentration of SnO2 in the dispersion is 0.1 mg / mL to 1 mg / mL.

2. The method for suppressing NiO according to claim 1 x The method for dispersion aggregation is characterized by, NiO x NiO in dispersion x The concentration is 10 mg / mL to 15 mg / mL.

3. The method for suppressing NiO according to claim 1 x The method for dispersion aggregation is characterized by, NiO x The specific preparation method of the dispersion is as follows: NiO x The powder is dispersed in a solvent and ultrasonically mixed to make NiO x The powder is evenly dispersed to obtain basic NiO. x Dispersion; Basic NiO x The dispersion was stirred and mixed with SnO2 hydrocolloid to make NiO x The accumulation of positive charge on the surface of nanoparticles yields NiO. x Dispersion.

4. The method for suppressing NiO according to claim 3 x The method for dispersion aggregation is characterized by, The particle size of SnO2 in SnO2 hydrocolloid is 5nm to 20nm.

5. The method for suppressing NiO according to claim 3 x The method for dispersion aggregation is characterized by, The mixing method is as follows: mix at a stirring speed of 300 rpm to 600 rpm for 5 min to 10 min under conditions of 25℃ to 35℃.

6. The method for suppressing NiO according to claim 3 x The method for dispersion aggregation is characterized by, NiO x NiO in dispersion x The average particle size of the nanoparticles is 15 nm to 20 nm.

7. The method for suppressing NiO according to claim 3 x The method for dispersion aggregation is characterized by, The solvent is water.

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