Application of triazole formamide, perovskite precursor solution as well as preparation method and application of perovskite precursor solution

Abstract

The invention belongs to the technical field of perovskite materials, and particularly relates to application of triazole formamide, a perovskite precursor solution and a preparation method and application of the perovskite precursor solution, triazole formamide serves as an additive to be added into perovskite, and triazole formamide is 1, 2, 4 triazole-3-formamide. According to the method, the homogenization of the large-area film is realized and the defects in the perovskite polycrystalline film are effectively passivated in the nucleation and crystallization process in the process of preparing the large-area perovskite polycrystalline film by using the small-molecule triazole formamide as the multi-active-site additive regulation and control solution method; therefore, the photoelectric conversion efficiency and the stability of the perovskite photovoltaic miniature module are improved.

Description

Technical Field

[0001] This invention belongs to the field of perovskite material technology, specifically relating to the application of triazole formamide, perovskite precursor solution and its preparation method and application. Background Technology

[0002] With the advancement of technology and the continuous improvement of scientific and technological development, the demand for energy has increased dramatically, leading to the problem of energy depletion. Simultaneously, environmental pollution has become increasingly serious along with the rapid consumption of energy. To achieve sustainable development, developing and using recyclable, green, low-carbon, and clean energy is an inevitable trend in human development. Among these, solar energy is not limited by geographical conditions or the environment, leading to the rapid development of photovoltaic products and the emergence of perovskite, a third-generation photovoltaic material. Currently, the rapid development of perovskite photovoltaics is still concentrated in small areas (<1 cm²). 2 Improving the performance of photovoltaic devices, and fabricating perovskite photovoltaic micro-modules to enhance their photoelectric conversion efficiency, is a crucial way to promote the industrialization of perovskite solar cells. However, in the process of expanding manufacturing from small-area solar cells to large-area perovskite modules, the insufficient uniformity and numerous defects in large-area perovskite films prepared by solution methods can severely affect the improvement of photoelectric conversion efficiency and stability. Summary of the Invention

[0003] Based on the decreased photoelectric conversion efficiency and stability caused by the inhomogeneity and increased defects in large-area perovskite thin films, this invention discovers that using small-molecule triazole formamide as a multi-active-site additive can regulate the interaction between solvent and solute in the perovskite precursor solution, thereby modulating the nucleation and crystallization process of perovskite polycrystalline thin films. Furthermore, due to its high boiling point, it is retained in the film to passivate defects and improve stability. Simultaneously, this invention can significantly improve the fill factor and short-circuit current of perovskite photovoltaic micro-modules, thereby enhancing photoelectric conversion efficiency and improving the stability of device storage in air.

[0004] The technical solution adopted by the present invention to achieve the above objectives is as follows: In a first aspect, the present invention provides an application of triazole formamide, wherein the triazole formamide is added as an additive to perovskite, wherein the triazole formamide is 1,2,4-triazole-3-carboxamide, and its molecular structural formula is: .

[0005] Preferably, the 1,2,4-triazole-3-carboxamide, as a small molecule multi-active site additive, regulates the interaction between solvent and solute in the perovskite precursor solution, thereby regulating the nucleation and crystallization process of the perovskite film. Due to its high boiling point, it is retained in the perovskite film to passivate defects and improve stability.

[0006] Secondly, the present invention provides a perovskite precursor solution, wherein the solution system is a mixed solution of N,N-dimethylformamide and N-methylpyrrolidone, and contains 1,2,4-triazole-3-carboxamide as an additive.

[0007] Preferably, the volume ratio of N,N-dimethylformamide to N-methylpyrrolidone is 6-9:1.

[0008] Preferably, the concentration of 1,2,4-triazole-3-carboxamide in the perovskite precursor solution is 0.5-1.5 mg / mL.

[0009] Preferably, the perovskite is composed of FA. x Cs 1-x PbI3, where 0 < x < 1.

[0010] Thirdly, the present invention provides a method for preparing the perovskite precursor solution, comprising the following steps: S1: Dissolve the raw materials in a mixed solvent of N,N-dimethylformamide and N-methylpyrrolidone according to the molar ratio; S2: Add the additive to the mixed solution obtained in step S1 and stir until dissolved to obtain the perovskite precursor solution.

[0011] Preferably, in step S1, the raw materials are formamidinium iodide, cesium iodide, lead iodide, and butylamine hydrochloride.

[0012] Fourthly, the present invention provides a perovskite photovoltaic micro-module, wherein the perovskite precursor solution is coated on the surface of the transport layer to prepare a perovskite thin film.

[0013] Preferably, the perovskite thin film is a light-absorbing layer. The beneficial effects of this invention are as follows: This invention uses small-molecule triazole formamide as a multi-active-site additive to regulate the nucleation and crystallization process in the solution method for preparing large-area perovskite polycrystalline thin films, thereby achieving homogenization of the large-area film and effectively passivating defects in the perovskite polycrystalline thin film, thus improving the photoelectric conversion efficiency and stability of the perovskite photovoltaic micro-module.

[0014] This invention provides a simple and easy-to-use method for modifying perovskite photovoltaic micro-modules with additives to improve their photoelectric conversion efficiency and stability. Small-molecule additives with structures similar to the solvent are used to regulate the dissociation process between the solvent and solute during nucleation and crystallization, achieving uniform crystallization of large-area perovskite films and retaining passivation defects within the perovskite film, thereby effectively suppressing non-radiative recombination. Theoretical characterization shows that additive modification can significantly improve the uniformity of crystallization and radiative recombination of perovskite films; and can effectively suppress the partitioning process of perovskite films by moisture in the air. This novel and simple additive strategy can significantly improve the photoelectric conversion efficiency and stability of perovskite photovoltaic micro-modules. Attached Figure Description

[0015] Figure 1 The diagram shows the structure and physical image of the perovskite photovoltaic micro-module prepared according to this invention. Figure 2 These are X-ray diffraction patterns of nine different regions of a large-area perovskite thin film before and after modification in this invention. Figure 3 Photoluminescence diagrams of nine different regions of a large-area perovskite thin film before and after modification. Figure 4 The graphs show the photoelectric conversion efficiency of large-area perovskite photovoltaic micro-modules before and after modification. Figure 5 Statistical chart of device-related parameters for large-area perovskite photovoltaic micro-modules before and after modification. Figure 6 Stability curves of perovskite photovoltaic micro-modules before and after modification in air storage. Detailed Implementation The technical solution of the present invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] In this embodiment of the invention, the method for fabricating a perovskite photovoltaic micro-module includes the following steps: Step 1: Use a nanosecond laser to perform P1 etching on the complete FTO substrate; after etching, the substrate is ultrasonically cleaned sequentially with water, acetone, and ethanol; the cleaned FTO substrate is dried with a nitrogen gas gun and treated with ultraviolet ozone for 15 minutes; an aqueous dispersion of nickel oxide nanoparticles is rod-coated and deposited on the substrate, and then transferred to a heating stage for annealing to prepare a nickel oxide hole transport layer; further, a solution of a monomolecular self-assembled layer is rod-coated and deposited on the nickel oxide hole transport layer, and then heated and annealed to prepare a composite hole transport layer; Step 2: The perovskite precursor solution of the present invention is coated onto the surface of the composite hole transport layer prepared in Step 1 by rod coating, and then transferred to a heating stage to complete the annealing treatment to prepare a perovskite thin film. Step 3: Using vacuum thermal deposition technology, the electron transport layer C is deposited. 60 The barrier layer BCP material is sequentially deposited on the surface of the perovskite thin film prepared in step two, and then P2 etching is performed using a nanosecond green laser. After etching, the metal electrode is multiplied on the top layer of BCP. Finally, P3 and P4 etching are performed using a nanosecond green laser to obtain the perovskite photovoltaic micro-module.

[0017] In step one, the concentration of the nickel oxide nanoparticle aqueous dispersion is 10 mg / mL, the rod coating speed is 10 mm / s, and the annealing conditions are 150°C for 30 minutes.

[0018] In step two, the concentration of the perovskite precursor solution is 1.1 mol / L; the bar coating method is: 5 mm / s, air knife pre-crystallization for 50 seconds, and annealing conditions are 100℃ for 30 minutes.

[0019] In step three, the deposition thicknesses of the C60, BCP, and Cu electrodes are 20 nm, 8 nm, and 100 nm, respectively.

[0020] Example 1 Perovskite FA 0.83 Cs 0.17 Preparation of PbI3 precursor solution: FAI (formamidine iodide), CsI (cesium iodide), PbI2 (lead iodide), and BACl (butylamine hydrochloride) were mixed and dissolved in a mixed solvent of DMF (N,N-dimethylformamide) and NMP (N-methylpyrrolidone) (9:1) to prepare a solution with a molar concentration of 1.1 mol / L.

[0021] The solution was incubated in air and stirred for 12 hours, then filtered through a 0.45 μm PTFE filter. The filtrate was collected. 1 mg of 1,2,4-triazole-3-carboxamide was added to each 1 mL portion of the filtrate at the specified molar ratio. The mixture was stirred thoroughly for 3 hours to obtain the modified perovskite precursor solution.

[0022] Example 2 The difference between this embodiment and Example 1 is that the volume ratio of DMF (N,N-dimethylformamide) to NMP (N-methylpyrrolidone) is 8:1, the perovskite concentration is 1.2 mol / mL, and the concentration of 1,2,4-triazole-3-carboxamide is 0.5 mg / mL.

[0023] Example 3 The difference between this embodiment and Example 1 is that the volume ratio of DMF (N,N-dimethylformamide) to NMP (N-methylpyrrolidone) is 6:1, the perovskite concentration is 1.3 mol / mL, and the concentration of 1,2,4-triazole-3-carboxamide is 1.5 mg / mL.

[0024] Comparative Example 1 Perovskite FA 0.83 Cs 0.17 Preparation of PbI3 precursor solution: FAI (formamidine iodide), CsI (cesium iodide), PbI2 (lead iodide), and BACl (butylamine hydrochloride) were mixed and dissolved in a mixed solvent of DMF (N,N-dimethylformamide) and NMP (N-methylpyrrolidone) (9:1) to prepare a solution with a molar concentration of 1.1 mol / L.

[0025] The solution was placed in air and stirred for 12 hours, then filtered using a 0.45 μm PTFE filter. The filtrate was collected to obtain the perovskite precursor solution.

[0026] Application Example 1 Device Examples (1) FTO glass substrate treatment and hole transport layer preparation The entire FTO substrate was P1 etched using a nanosecond laser. After etching, the substrate was ultrasonically cleaned with water, acetone, and ethanol for 20 minutes in sequence. The cleaned FTO substrate was dried with a nitrogen gas gun and treated with ultraviolet ozone for 15 minutes. An aqueous dispersion of nickel oxide nanoparticles with a concentration of 10 mg / ml was rod-coated onto the substrate at a rod-coating speed of 10 mm / s and then transferred to a heating stage for annealing at 150°C for 30 minutes to prepare a nickel oxide hole transport layer. Further, an ethanol solution of [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz) with a concentration of 1 mg / mL was rod-coated onto the nickel oxide hole transport layer. The rod-coating process parameters were the same as those for nickel oxide. The substrate was then annealed on a heating stage at 100°C for 10 minutes to complete the preparation of the composite hole transport layer.

[0027] (2) Preparation of perovskite thin films The perovskite precursor solutions from Example 1 and Comparative Example 1 were respectively rod-coated onto the surface of the composite transport layer prepared in step (1) at a rod-coating speed of 5 mm / s, and pre-crystallized by blowing with a nitrogen air knife at 0.3 MPa for 40 seconds. The films were then transferred to a hot stage at 100°C for annealing for 30 minutes.

[0028] (3) Laser scribing to form a series region and vacuum evaporation to prepare an electron transport layer and a metal electrode layer The prepared perovskite thin film was filled into a deposition mask using vacuum thermal deposition technology and placed in a vacuum deposition chamber; the chamber was evacuated until the gas pressure inside was less than 3 × 10⁻⁶. -4 After Pa, 20nm C is sequentially thermally vapor-deposited. 60 An 8nm BCP was formed, followed by P2 etching using a nanosecond green laser. After etching, a metal electrode was multiplied on top of the BCP. Finally, P3 and P4 etching were performed using a nanosecond green laser to obtain the perovskite photovoltaic micromodule. The large-area perovskite thin film and perovskite photovoltaic micromodule prepared using the perovskite precursor solution in Comparative Example 1 and Example 1 were designated as the control group and optimization group, respectively.

[0029] The schematic diagram of the fabricated perovskite photovoltaic micro-module device structure and the actual device are shown below. Figure 1 As shown, a is a schematic diagram of the battery structure, b is a geometric design diagram of the perovskite module, and c is a physical image of the perovskite photovoltaic micro-module.

[0030] The X-ray diffraction intensity and photoluminescence spectra of the large-area perovskite thin films prepared in Example 1 and Comparative Example 1 were measured in nine selected regions, as shown below. Figure 2 and Figure 3 As shown in the figure, the test results indicate that the additive-modified large-area perovskite film exhibits significantly improved crystal uniformity, which is beneficial for enhancing the device performance of large-area photovoltaic modules. Furthermore, the significant improvement in photoluminescence intensity and uniformity demonstrates that the additive effectively passivates defects in the perovskite film and suppresses non-radiative recombination.

[0031] The optimal photoelectric conversion efficiency of the large-area perovskite photovoltaic micro-modules prepared using the perovskite precursor solutions in Example 1 and Comparative Example 1 is as follows: Figure 4 As shown. Test light source: AM 1.5 (solar simulator-Oriel91160-1000, 300W), data acquisition used Keithley 2400 digital source meter. The short-circuit photocurrents of the devices reached 56.55 and 57.3 mA, respectively; the open-circuit voltages were 6.5 and 6.7 V, respectively; the fill factors (FF) were 74.35% and 76.43%, respectively; and the photoelectric conversion efficiencies reached 18.22% and 19.54%, respectively. Furthermore, the photoelectric conversion efficiencies of more devices were statistically analyzed, as shown below. Figure 5 As shown, the efficiency of the modified device is significantly improved.

[0032] The stability of the photoelectric conversion efficiency of the large-area perovskite photovoltaic micro-modules prepared using the perovskite precursor solutions in Example 1 and Comparative Example 1 stored in ambient air is as follows: Figure 6As shown, the photoelectric conversion efficiency of the control device dropped to less than 80% of the initial efficiency after 144 hours, while the optimized device still maintained more than 80% of the initial efficiency after 350 hours of aging, demonstrating that the device stability was significantly improved.

[0033] It should be further noted that the above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An application of triazole carboxamide, characterized in that: The triazole formamide is added as an additive to the perovskite, wherein the triazole formamide is 1,2,4-triazole-3-carboxamide.

2. The application of triazole carbamide according to claim 1, characterized in that: The 1,2,4-triazole-3-carboxamide, as a small molecule multi-active site additive, regulates the interaction between solvent and solute in the perovskite precursor solution, thereby regulating the nucleation and crystallization process of the perovskite film. Due to its high boiling point, it is retained in the perovskite film to passivate defects and improve stability.

3. A perovskite precursor solution, characterized in that: The solution system used is a mixed solution of N,N-dimethylformamide and N-methylpyrrolidone, and contains 1,2,4-triazole-3-carboxamide as an additive.

4. The perovskite precursor solution according to claim 3, characterized in that: The volume ratio of N,N-dimethylformamide to N-methylpyrrolidone is 6-9:

1.

5. The perovskite precursor solution according to claim 3, characterized in that: The concentration of 1,2,4-triazole-3-carboxamide in the perovskite precursor solution is 0.5-1.5 mg / mL.

6. The perovskite precursor solution according to claim 3, characterized in that: The perovskite is composed of FA. x Cs 1- x PbI3, where 0 < x < 1.

7. A method for preparing a perovskite precursor solution according to any one of claims 3-6, characterized in that, Includes the following steps: S1: Dissolve the raw materials in a mixed solvent of N,N-dimethylformamide and N-methylpyrrolidone according to the molar ratio; S2: Add the additive to the mixed solution obtained in step S1 and stir until dissolved to obtain the perovskite precursor solution.

8. The method for preparing the perovskite precursor solution according to claim 7, characterized in that: In step S1, the raw materials are formamidinium iodide, cesium iodide, lead iodide, and butylamine hydrochloride.

9. A perovskite photovoltaic micro-module, characterized in that: A perovskite thin film is prepared by coating the perovskite precursor solution according to any one of claims 3-6 or the perovskite precursor solution prepared by the preparation method according to claim 7 or 8 onto the surface of the transport layer.

10. The perovskite photovoltaic micro-module according to claim 9, characterized in that: The perovskite thin film is a light-absorbing layer.

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