Perovskite battery with self-assembled monomolecular layer and preparation method thereof

Abstract

The invention relates to a perovskite cell with a self-assembly monomolecular layer and a preparation method, and a perovskite assembly with the self-assembly monomolecular layer is suitable for being arranged on an external substrate, and comprises a transparent conductive layer, a hole transport layer, a perovskite active layer, an electron transport layer, a hole barrier layer, a back electrode and the self-assembly monomolecular layer. Wherein the self-assembled monomolecular layer is arranged between the hole transport layer and the perovskite active layer, a solution of a precursor of the self-assembled monomolecular layer comprises phosphorylcholine chloride and Me-4PACz, and a solvent of the precursor of the self-assembled monomolecular layer is a mixed solvent of ethanol and isopropanol; according to the invention, the phosphorylcholine chloride and the Me-4PACz are introduced, so that the interface performance, the photoelectric conversion efficiency and the long-term stability of the perovskite cell are remarkably optimized.

Description

Technical Field

[0001] The invention discloses a perovskite photovoltaic cell technology field, and relates to a perovskite cell with a self-assembled monolayer and a preparation method thereof. Background Art

[0002] Perovskite Solar Cells (PSCs) have emerged in the photovoltaic field with their excellent high photoelectric conversion efficiency and low-cost preparation characteristics, becoming a strong competitor for the next generation of photovoltaic technology with great potential. However, in the research and development and application of perovskite solar cell devices, interface characteristics play a crucial role, which directly affects the efficiency performance and stability level of the device. In particular, self-assembled monolayers (Self-Assembled Monolayers, SAMs), as a key material, are widely used as hole transport layers (HTL) in the structure of inverted perovskite solar cells (Inverted PSC, i-PSCs). Through a unique molecular self-assembly mechanism, self-assembled monolayers can accurately control the alignment of interface energy levels, thereby significantly improving the carrier transmission efficiency, while effectively reducing the non-radiative recombination phenomenon caused by interface defect states, thereby providing strong support for the improvement of the performance of perovskite solar cell devices.

[0003] Nevertheless, traditional self-assembled monolayers still have some limitations that cannot be ignored. On the one hand, some self-assembled monolayers, such as Me-4PACz, have relatively low surface polarity, which leads to poor wettability of the precursor solution during the actual preparation process. This problem directly interferes with the uniform deposition of the perovskite active layer, thus affecting the overall performance of the device. Summary of the invention

[0004] In view of this, the present application provides a perovskite cell with a self-assembled monolayer and a preparation method, which improves the limitations of traditional self-assembled monolayers in the preparation of perovskite cells by doping or mixing different organic small molecules or functionalized ligands in the self-assembled monolayer.

[0005] According to one aspect of the present application, a perovskite cell with a self-assembled monolayer is provided. The perovskite cell with a self-assembled monolayer is suitable for being arranged on an external substrate, and comprises a transparent conductive layer, a hole transport layer, a perovskite active layer, an electron transport layer, a hole blocking layer, a back electrode and a self-assembled monolayer; the transparent conductive layer is arranged on the external substrate, the hole transport layer is arranged on the transparent conductive layer, the perovskite active layer is arranged on the hole transport layer, the electron transport layer is arranged on the perovskite active layer, the hole blocking layer is arranged on the electron transport layer, and the back electrode is arranged on the hole blocking layer; wherein the self-assembled monolayer is arranged between the hole transport layer and the perovskite active layer, and the solution of the precursor of the self-assembled monolayer comprises phosphorylcholine chloride and Me-4PACz, and the solvent of the precursor of the self-assembled monolayer is a mixed solvent of ethanol and isopropanol.

[0006] According to one aspect of the present application, the transparent conductive layer is indium tin oxide or fluorine-doped tin oxide or a transparent conductive layer doped with a metal oxide; the hole transport layer is nickel oxide or poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) or 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene.

[0007] According to one aspect of the present application, the precursor solution of the perovskite active layer comprises a cation at position A, a metal cation at position B and an anion at position X; the electron transport layer is fullerene or [6,6]-phenyl-C 61 -methyl butyrate or tin dioxide layer; the hole blocking layer is a bath copper layer or a lithium fluoride layer; the back electrode is a metal layer.

[0008] A method for preparing a perovskite battery with a self-assembled monolayer includes the above-mentioned perovskite battery with a self-assembled monolayer, specifically comprising the following steps: step one: depositing a transparent conductive layer on the external substrate, wherein the external substrate is a supporting structure of the perovskite battery; step two: preparing a hole transport layer on the transparent conductive layer; step three: preparing a self-assembled monolayer on the hole transport layer; step four: preparing a perovskite active layer on the self-assembled monolayer; step five: depositing an electron transport material on the perovskite active layer to form an electron transport layer; step six: preparing a hole blocking layer on the electron transport layer; step seven: depositing a back electrode on the hole blocking layer.

[0009] According to one aspect of the present application, the specific steps of preparing the self-assembled monolayer on the hole transport layer include: first preparing three mixed solvents of the ethanol and the isopropanol, namely solvent one, solvent two and solvent three; then adding Me-4PACz to solvent one to form solution one, and adding phosphorylcholine chloride to solvent two to form solution two; then adding the obtained solution one and solution two to solvent three, and fully dissolving them by magnetic stirring to obtain a precursor of the self-assembled monolayer.

[0010] According to one aspect of the present application, Me-4PACz with a dissolution concentration of 0.1~0.5 mg / mL is added to solvent one; phosphorylcholine chloride with a dissolution concentration of 0.05~0.5 mg / mL is added to solvent two; the obtained solution one and solution two are then added to solvent three, and the solution is fully dissolved by magnetic stirring, and the molar ratio of Me-4PACz to phosphorylcholine chloride is 10:1~1:1, the volume ratio of the ethanol and the isopropanol in solvent three is 1:1~3:1, and the total concentration is controlled at 0.2~1.0 mg / mL, which is a precursor of the self-assembled monolayer.

[0011] According to one aspect of the present application, the precursor of the self-assembled monolayer is uniformly printed on the hole transport layer at a speed of 5-50 mm / s to form a self-assembled monolayer film.

[0012] According to one aspect of the present application, the self-assembled monolayer is formed and annealed at a temperature of 80-120 degrees Celsius for a time of 10-30 minutes to obtain the self-assembled monolayer.

[0013] According to one aspect of the present application, the total thickness of the self-assembled monolayer is 1-5 nm.

[0014] According to one aspect of the present application, the self-assembled monolayer is prepared by coating, spin coating, self-assembly deposition or spraying.

[0015] The beneficial effects of the present application are as follows: by introducing phosphorylcholine chloride and Me-4PACz, the interface performance, photoelectric conversion efficiency and long-term stability of the perovskite battery are significantly optimized. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the molecular formula of phosphorylcholine chloride of the perovskite cell with self-assembled monolayer in this embodiment; Figure 2 is the molecular formula of Me-4PACz of the perovskite cell with self-assembled monolayer in this embodiment; Figure 3 is the contact angle diagram of Me-4PACz deposited on the surface of the hole transport layer; Figure 4 is the contact angle diagram of p-aminobenzenethiol-Me-4PACz deposited on the surface of the hole transport layer; Figure 5 is the contact angle diagram of phosphorylcholine chloride-Me-4PACz deposited on the surface of the hole transport layer; Figure 6 The bottom surface SEM image of the perovskite active layer deposited on Me-4PACz; Figure 7 The SEM image of the bottom surface of the perovskite active layer deposited on p-aminobenzenethiol-Me-4PACz; Figure 8 The bottom surface SEM image of the perovskite active layer deposited on phosphorylcholine chloride-Me-4PACz; Fig. 9 Large-area perovskite cells for different self-assembled monolayers J - V Graphs; Fig.10 Large-area perovskite cells with self-assembled monolayers formed by co-doping phosphorylcholine chloride-Me-4PACz at different molar ratios J - V Graphs; Fig.11 FIG. 4 is a detailed structural diagram of the perovskite cell with a self-assembled monolayer according to the present embodiment. DETAILED DESCRIPTION

[0017] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0018] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0019] like Figures 1 to 11As shown, the present application provides a perovskite cell with a self-assembled monolayer, and the perovskite cell with a self-assembled monolayer is suitable for being arranged on an external substrate, including a transparent conductive layer 1, a hole transport layer 2, a perovskite active layer 4, an electron transport layer 5, a hole blocking layer 6, a back electrode 7 and a self-assembled monolayer 3; the transparent conductive layer 1 is arranged on the external substrate, the hole transport layer 2 is arranged on the transparent conductive layer 1, the perovskite active layer 4 is arranged on the hole transport layer 2, the electron transport layer 5 is arranged on the perovskite active layer 4, the hole blocking layer 6 is arranged on the electron transport layer 5, and the back electrode 7 is arranged on the hole blocking layer 6; wherein the self-assembled monolayer 3 is arranged between the hole transport layer 2 and the perovskite active layer 4, and the solution of the precursor of the self-assembled monolayer 3 includes phosphorylcholine chloride and Me-4PACz, and the solvent of the precursor of the self-assembled monolayer 3 is a mixed solvent of ethanol and isopropanol.

[0020] Specifically, the substrate serves as the supporting structure of the solar cell, and a transparent conductive layer 1 is deposited thereon, which is used as an electrode material for subsequent charge collection and transport. A hole transport layer 2 is prepared on the transparent conductive layer 1 to help holes be effectively transported from the perovskite active layer 4 to the electrode. Then a self-assembled monolayer 3 is prepared on the hole transport layer 2 to effectively passivate the interface. The precursor material of the perovskite active layer 4 is coated on the self-assembled monolayer 3 to form the perovskite active layer 4. An electron transport material is deposited on the perovskite active layer 4 to form an electron transport layer 5 to help electrons be transported from the perovskite active layer 4 to the electrode layer, and then a hole blocking layer 6 is prepared on the electron transport layer 5 to protect the perovskite active layer 4 and the electron transport layer 5 and promote the efficiency of charge collection. Finally, the back electrode 7 is deposited as the top electrode of the entire solar cell, and the prepared perovskite cell is packaged and tested. The packaging can prevent the impact of environmental conditions on device performance, such as changes in light and humidity. The packaged perovskite cell also needs to be tested for performance, including photoelectric conversion efficiency (PCE), short-circuit current density (Jsc), open circuit voltage (Voc) and fill factor (FF), to evaluate the photoelectric conversion efficiency and stability during the process.

[0021] Furthermore, the transparent conductive layer 1 is a transparent conductive layer 1 of indium tin oxide or fluorine-doped tin oxide or doped metal oxide; the hole transport layer 2 is nickel oxide or PEDOT:PSS (i.e., poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid)) or 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene.

[0022] Specifically, the precursor solution of the perovskite active layer 4 contains cations at the A position, metal cations at the B position, and anions at the X position; the electron transport layer 5 is fullerene or [6,6]-phenyl-C 61-methyl butyrate or tin dioxide layer; the hole blocking layer 6 is a copper bath layer or a lithium fluoride layer; the back electrode 7 is a metal layer.

[0023] A method for preparing a perovskite battery with a self-assembled monolayer includes the above-mentioned perovskite battery with a self-assembled monolayer, specifically comprising the following steps: step one: depositing a transparent conductive layer 1 on an external substrate, the external substrate being a supporting structure of the perovskite battery; step two: preparing a hole transport layer 2 on the transparent conductive layer 1; step three: preparing a self-assembled monolayer 3 on the hole transport layer 2; step four: preparing a perovskite active layer 4 on the self-assembled monolayer 3; step five: depositing an electron transport material on the perovskite active layer 4 to form an electron transport layer 5; step six: preparing a hole blocking layer 6 on the electron transport layer 5; step seven: depositing a back electrode 7 on the hole blocking layer 6.

[0024] Furthermore, the specific steps of preparing the self-assembled monolayer 3 on the hole transport layer 2 include: first preparing three mixed solvents of ethanol and isopropanol, namely solvent one, solvent two and solvent three; then adding Me-4PACz to solvent one to form solution one, and adding phosphorylcholine chloride to solvent two to form solution two; then adding the obtained solution one and solution two to solvent three, and fully dissolving them by magnetic stirring to obtain a precursor of the self-assembled monolayer 3.

[0025] Specifically, Me-4PACz with a dissolving concentration of 0.1~0.5 mg / mL is added to solvent one; phosphorylcholine chloride with a dissolving concentration of 0.05~0.5 mg / mL is added to solvent two; the obtained solution one and solution two are added to solvent three, and they are fully dissolved by magnetic stirring, and the molar ratio of Me-4PACz to phosphorylcholine chloride is 10:1~1:1, the volume ratio of ethanol and isopropanol in solvent three is 1:1~3:1, and the total concentration is controlled at 0.2~1.0 mg / mL, which is a precursor of self-assembled monolayer 3.

[0026] Furthermore, the precursor of the self-assembled monolayer 3 is uniformly printed on the hole transport layer 2 at a speed of 5-50 mm / s, and the distance between the coated meniscus and the hole transport layer 2 is 80-120 μm, thereby forming a self-assembled monolayer film.

[0027] Afterwards, the self-assembled monomolecular film is annealed at a temperature of 80-120 degrees Celsius for a time of 10-30 minutes to obtain a self-assembled monomolecular layer 3.

[0028] More specifically, the total thickness of the self-assembled monolayer 3 is 1-5 nm, and such a setting can ensure dense coverage without affecting charge transport.

[0029] In order to meet different preparation environments and process requirements, the self-assembled monolayer 3 is prepared by coating, spin coating, self-assembly deposition or spraying.

[0030] The present invention solves the interface defect problem between the hole transport layer 2 and the perovskite active layer 4 in the perovskite battery by forming a co-self-assembled monolayer 3 co-doped with Me-4PACz and phosphorylcholine chloride. The design uses a synergistic anchoring mechanism of bifunctional groups to simultaneously passivate the oxygen vacancies on the substrate surface and the halogen vacancy defects in the perovskite active layer 4, breaking through the coverage limit of the traditional single self-assembled monolayer. The formation of an intermolecular interwoven network not only enhances the interface bonding strength, but also reduces the carrier transport barrier by optimizing the energy level gradient.

[0031] In the traditional single self-assembled monolayer, although Me-4PACz effectively improves the electrical properties of the interface, due to its rigid structure, it is difficult to densely cover the surface, resulting in limited passivation effect. By introducing phosphorylcholine chloride, the co-adsorption strategy of the self-assembled monolayer 3 can fill the gaps in the Me-4PACz layer, forming a denser self-assembled monolayer 3, improving the passivation effect and electron transport capacity of the interface. The phosphate groups and chloride ions in phosphorylcholine chloride can effectively suppress the oxygen vacancies and metal ion defects on the surface of the hole transport layer 2, while filling the organic cations and halogen vacancies at the bottom of the perovskite active layer, further repairing the defects in the perovskite active layer 4.

[0032] This self-assembled monolayer 3 not only reduces non-radiative recombination by promoting the growth of perovskite crystals, but also promotes efficient carrier transport by optimizing band alignment. In addition, the dense self-assembled layer of phosphorylcholine chloride and Me-4PACz relieves the residual stress of the perovskite active layer, thereby improving the stability of the perovskite active layer. This stress relief helps reduce the crack generation of the material and enhances the durability of the perovskite active battery during long-term operation.

[0033] in, Figures 1 to 11 The PC appearing therein is phosphorylcholine chloride, Me is Me-4PAC, PC-Me is phosphorylcholine chloride-Me-4PACz, and PC:Me is the molar ratio of phosphorylcholine chloride:Me-4PACz.

[0034] The following is a specific description with reference to the following embodiments and comparative examples: Example 1 A preparation method of a perovskite cell having a self-assembled monolayer comprises the following steps: Step 1: depositing a transparent conductive layer 1 on an external substrate; Step 2: depositing a nickel oxide thin film as the hole transport layer 2 on the transparent conductive layer 1 by a high-precision magnetron sputtering process; Step 3: preparing a self-assembled monolayer 3 on the hole transport layer 2, dissolving two self-assembled molecules with complementary functions in an ethanol / isopropanol mixed solvent respectively, depositing them on the hole transport layer 2 step by step through a coating process, and annealing, with a coating speed of 30 mm / s, an annealing temperature of 100 degrees Celsius, and an annealing time of 10 minutes; Step 4: Then, a perovskite active layer 4 precursor solution is coated on the surface of the self-assembled monolayer 3, and annealed to form the perovskite active layer 4; Step 5: depositing electron transport material on the perovskite active layer 4 to form an electron transport layer 5; Step 6: preparing a hole blocking layer 6 on the electron transport layer 5; Step seven: depositing a back electrode 7 on the hole blocking layer 6 .

[0035] The electron transport layer 5 and the hole blocking layer 6 are uniformly prepared by thermal evaporation deposition of fullerene and bathocuproin; the back electrode 7 adopts a magnetron sputtering copper / indium tin oxide composite electrode structure.

[0036] Preparation steps of self-assembled monolayer 3: First, prepare three mixed solvents of ethanol and isopropanol, namely solvent one, solvent two and solvent three; Then, Me-4PACz with a dissolving concentration of 0.1 mg / mL was added to solvent one to form solution one, and phosphorylcholine chloride with a dissolving concentration of 0.05 mg / mL was added to solvent two to form solution two; Then, the obtained solution 1 and solution 2 are added to the solvent 3, and Me-4PACz and phosphorylcholine chloride are mixed in a molar ratio of 1:1, and are fully dissolved by magnetic stirring to obtain a precursor of the self-assembled monolayer 3.

[0037] Example 2 A preparation method of a perovskite cell having a self-assembled monolayer comprises the following steps: Step 1: depositing a transparent conductive layer 1 on an external substrate; Step 2: depositing a nickel oxide thin film as the hole transport layer 2 on the transparent conductive layer 1 by a high-precision magnetron sputtering process; Step 3: preparing a self-assembled monolayer 3 on the hole transport layer 2, dissolving two self-assembled molecules with complementary functions in an ethanol / isopropanol mixed solvent respectively, depositing them on the hole transport layer 2 step by step through a coating process, and annealing, with a coating speed of 30 mm / s, an annealing temperature of 100 degrees Celsius, and an annealing time of 10 minutes; Step 4: Then, a perovskite active layer 4 precursor solution is coated on the surface of the self-assembled monolayer 3, and annealed to form the perovskite active layer 4; Step 5: depositing electron transport material on the perovskite active layer 4 to form an electron transport layer 5; Step 6: preparing a hole blocking layer 6 on the electron transport layer 5; Step seven: depositing a back electrode 7 on the hole blocking layer 6 .

[0038] The electron transport layer 5 and the hole blocking layer 6 are uniformly prepared by thermal evaporation deposition of fullerene and bathocuproin; the back electrode 7 adopts a magnetron sputtering copper / indium tin oxide composite electrode structure.

[0039] Preparation steps of self-assembled monolayer 3: First, prepare three mixed solvents of ethanol and isopropanol, namely solvent one, solvent two and solvent three; Then, Me-4PACz with a dissolving concentration of 0.3 mg / mL was added to solvent one to form solution one, and phosphorylcholine chloride with a dissolving concentration of 0.25 mg / mL was added to solvent two to form solution two; Then, the obtained solution 1 and solution 2 are added to the solvent 3, and Me-4PACz and phosphorylcholine chloride are mixed in a molar ratio of 1:1.5, and are fully dissolved by magnetic stirring to obtain a precursor of the self-assembled monolayer 3.

[0040] Example 3 A preparation method of a perovskite cell having a self-assembled monolayer comprises the following steps: Step 1: depositing a transparent conductive layer 1 on an external substrate; Step 2: depositing a nickel oxide thin film as the hole transport layer 2 on the transparent conductive layer 1 by a high-precision magnetron sputtering process; Step 3: preparing a self-assembled monolayer 3 on the hole transport layer 2, dissolving two self-assembled molecules with complementary functions in an ethanol / isopropanol mixed solvent respectively, depositing them on the hole transport layer 2 step by step through a coating process, and annealing, with a coating speed of 30 mm / s, an annealing temperature of 100 degrees Celsius, and an annealing time of 10 minutes; Step 4: Then, a perovskite active layer 4 precursor solution is coated on the surface of the self-assembled monolayer 3, and annealed to form the perovskite active layer 4; Step 5: depositing electron transport material on the perovskite active layer 4 to form an electron transport layer 5; Step 6: preparing a hole blocking layer 6 on the electron transport layer 5; Step seven: depositing a back electrode 7 on the hole blocking layer 6 .

[0041] The electron transport layer 5 and the hole blocking layer 6 are uniformly prepared by thermal evaporation deposition of fullerene and bathocuproin; the back electrode 7 adopts a magnetron sputtering copper / indium tin oxide composite electrode structure.

[0042] Preparation steps of self-assembled monolayer 3: First, prepare three mixed solvents of ethanol and isopropanol, namely solvent one, solvent two and solvent three; Then, Me-4PACz with a dissolving concentration of 0.5 mg / mL was added to the solvent one to form a solution one, and phosphorylcholine chloride with a dissolving concentration of 0.5 mg / mL was added to the solvent two to form a solution two; Then, the obtained solution 1 and solution 2 are added to the solvent 3, and Me-4PACz and phosphorylcholine chloride are mixed in a molar ratio of 1:2, and are fully dissolved by magnetic stirring to obtain a precursor of the self-assembled monolayer 3.

[0043] Comparative Example 1 The only difference from Example 1 is that the co-doped self-assembled monolayer 3 formed by phosphorylcholine chloride and Me-4PACz is replaced by Me-4PACz alone.

[0044] Comparative Example 2 The only difference from Example 1 is that phosphorylcholine chloride and Me-4PACz are replaced by p-aminobenzenethiol and Me-4PACz.

[0045] Figures 3 to 5 As shown, the contact angle test characterization based on the surface of different self-assembled monolayers 3 in Example 2, Comparative Example 1 and Comparative Example 2. From the contact angle, it can be observed that in the Me-4PACz system, the wettability at the interface is poor, such as Figure 3 As shown, the contact angle is 48.5 degrees. In Comparative Example 2, the synergistic effect of p-aminobenzenethiol is utilized, such as Figure 4 As shown, the contact angle is optimized to 36.3 degrees. In Example 2, the zwitterionic properties of phosphorylcholine chloride (hydrophilic phosphate group / hydrophobic choline group) cooperate with Me-4PACz to regulate the surface energy of the substrate and form a wetting interface, such as Figure 5 As shown, the Marangoni effect during the spreading of the precursor solution is suppressed.

[0046] like Figures 6 to 8 As shown, the morphology of the perovskite active layer 4 based on different self-assembled monolayers in Example 2, Comparative Example 1 and Comparative Example 2 is characterized. The perovskite active layer 4 deposited on phosphorylcholine chloride-Me-4PACz has almost no holes, such as Figure 8 As shown. The Me-4PACz system, such as Figure 6 As shown, the perovskite active layer 4 has more holes. Thiol-based molecules, such as Figure 7As shown, partial wetting results in insufficient coverage due to the surface energy mismatch of the perovskite active layer 4. In addition, phosphorylcholine chloride retards the solvent evaporation rate and induces heterogeneous nucleation, which, combined with the directional arrangement of the hole transport channels of Me-4PACz, generates a dense and uniform perovskite active layer 4, as shown Figure 8 As shown, water and oxygen penetration and I-migration paths are blocked, and the efficiency of perovskite cells is simultaneously improved.

[0047] The performance of the perovskite cells based on different self-assembled monolayers in Example 2, Comparative Example 1 and Comparative Example 2 was tested. The JV curves of the three perovskite cells with only Me-4PACz added, p-aminobenzenethiol-Me-4PACz co-doping and phosphorylcholine chloride-Me-4PACz co-doping are shown in Figure 2. Figure 3 As shown, the effective area of ​​the perovskite cell is 63.76 cm 2 , light intensity is AM1.5G 100mW / cm 2 .

[0048] Table 1 shows the performance parameters of three perovskite cells with only Me-4PACz added, co-doping with p-aminobenzenethiol-Me-4PACz and co-doping with phosphorylcholine chloride-Me-4PACz. It can be seen from Table 1 that compared with only adding Me-4PACz, the performance of the perovskite cell prepared by co-doping with p-aminobenzenethiol and Me-4PACz is slightly improved, while the various parameters of the perovskite cell prepared by introducing phosphorylcholine chloride are more significantly improved, among which the open circuit voltage (VOC) and fill factor (FF) are significantly improved, the fill factor is increased from 67.24% to 71.68%, the open circuit voltage is increased from 12.012V to 13.442V, and the photoelectric conversion efficiency (PCE) is increased from 13.83% to 16.66%.

[0049] Table 1 Performance parameters of three perovskite cells with different self-assembled monolayers The performance of the perovskite cells based on different self-assembled monolayers 3 in Example 1, Example 2, Example 3 and Comparative Example 1 was tested. The JV curves of the four perovskite cells with only Me-4PACz, phosphorylcholine chloride-Me-4PACz co-doping strategy with a molar ratio of 1:1, a molar ratio of 1:1.5 and a molar ratio of 1:2 are shown in FIG. Figure 4 As shown, the effective area of ​​the perovskite cell is 63.76 cm 2 , light intensity is AM1.5G 100mW / cm 2 .

[0050] Table 2 shows the performance parameters of four perovskite cells with only Me-4PACz added, phosphorylcholine chloride-Me-4PACz co-doping strategy with molar ratio of 1:1, molar ratio of 1:1.5 and molar ratio of 1:2. It can be seen from Table 2 that compared with only adding Me-4PACz, the phosphorylcholine chloride-Me-4PACz co-doping strategy can significantly improve the parameters of the perovskite cell, but it does not continue to optimize with the increase of concentration. The preferred molar ratio of phosphorylcholine chloride to Me-4PACz is 1:1.5. For different molar ratios under the co-doping strategy, the fill factor (FF) is most significantly improved, optimized to a maximum of 71.68%, the open circuit voltage (VOC) is increased from 13.019V to 13.442V, and the photoelectric conversion efficiency (PCE) is increased from 15.05% to 16.66%.

[0051] Table 2 Performance parameters of perovskite cells under different molar ratios of phosphorylcholine chloride-Me-4PACz co-doping strategy This application significantly optimizes the interface performance, photoelectric conversion efficiency and long-term stability of perovskite cells by introducing an interface engineering strategy of co-adsorption of phosphorylcholine chloride and Me-4PACz.

[0052] In the preparation of perovskite cells, compared with the control group Me-4PACz, the target group choline chloride-Me-4PACz showed significant advantages in improving the coverage of self-assembled monolayer 3 and improving interface energy level matching. With its unique chemical structure and spatial configuration, choline chloride-Me-4PACz forms a closer and more ordered interaction with the substrate and the perovskite active layer. This interaction enables choline chloride-Me to more effectively fill the microscopic defects on the substrate surface, thereby achieving a higher monolayer coverage under the same preparation conditions. At the same time, choline chloride-Me-4PACz is also particularly effective in improving interface energy level matching. It can accurately regulate the energy level relationship between the perovskite active layer and other functional layers, reduce the energy gap, and reduce the carrier transfer barrier, thereby optimizing the charge transfer process at the interface.

[0053] Phosphocholine chloride-Me-4PACz has a significant and profound effect on the improvement of film crystallization and defect state density. From the perspective of film crystallization, the introduction of phosphorylcholine chloride-Me-4PACz has greatly improved the crystallinity of the perovskite active layer, increased the grain size and made the distribution more uniform. Compared with Me-4PACz, the film prepared by phosphorylcholine chloride-Me-4PACz has higher crystallization quality and more perfect crystal structure. In addition, phosphorylcholine chloride-Me-4PACz also plays a key role in reducing the defect state density. Because phosphorylcholine chloride-Me-4PACz can effectively inhibit the formation of defects during the growth of perovskite, it reduces the recombination and scattering of carriers at the interface, further improving the photoelectric performance of perovskite cells.

[0054] On a large-area substrate, phosphorylcholine chloride-Me-4PACz can still maintain its excellent co-adsorption performance, ensuring the uniformity and stability of the self-assembled monolayer 3. According to actual measurements, the efficiency of the perovskite cell prepared by the present invention is increased from 13.83% to 16.66%, successfully achieving a large-area 63.76 cm 2 The uniform coating of the thin film provides a feasible technical path for large-scale and efficient production, meets the requirements of large-scale production, and provides solid technical support for the large-scale industrial production of perovskite batteries.

[0055] The application of phosphorylcholine chloride-Me-4PACz also significantly improves the stability of perovskite cells and extends their service life. After long-term aging tests, perovskite cells using phosphorylcholine chloride-Me-4PACz showed a lower performance decay rate, which was significantly lower than that using Me-4PACz. This is because phosphorylcholine chloride-Me-4PACz optimizes the interface structure and energy level matching, reduces the defect state density, and effectively inhibits the performance degradation of perovskite cells during use. This improved stability provides a guarantee for the long-term operation of perovskite cells in complex environments, laying a solid foundation for their wide application in the industrial field.

[0056] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A perovskite cell with a self-assembled monolayer, wherein the perovskite cell with a self-assembled monolayer is suitable for being arranged on an external substrate, characterized in that: It includes a transparent conductive layer, a hole transport layer, a perovskite active layer, an electron transport layer, a hole blocking layer, a back electrode and a self-assembled monolayer; The transparent conductive layer is disposed on the external substrate, the hole transport layer is disposed on the transparent conductive layer, the perovskite active layer is disposed on the hole transport layer, the electron transport layer is disposed on the perovskite active layer, the hole blocking layer is disposed on the electron transport layer, and the back electrode is disposed on the hole blocking layer; The self-assembled monolayer is arranged between the hole transport layer and the perovskite active layer, and the precursor solution of the self-assembled monolayer includes phosphorylcholine chloride and Me-4PACz, and the precursor solvent of the self-assembled monolayer is a mixed solvent of ethanol and isopropanol.

2. The perovskite cell with a self-assembled monolayer according to claim 1, characterized in that: The transparent conductive layer is a transparent conductive layer of indium tin oxide or fluorine-doped tin oxide or doped metal oxide; The hole transport layer is nickel oxide or poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) or 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene.

3. The perovskite cell with a self-assembled monolayer according to claim 1, characterized in that: The precursor solution of the perovskite active layer comprises a cation at the A site, a metal cation at the B site, and an anion at the X site; The electron transport layer is fullerene or [6,6]-phenyl-C 61 - methyl butyrate or tin dioxide layer; The hole blocking layer is a bath copper layer or a lithium fluoride layer; The back electrode is a metal layer.

4. A method for preparing a perovskite battery with a self-assembled monolayer, characterized in that: A perovskite cell with a self-assembled monolayer as claimed in any one of claims 1 to 3, comprising the following steps: Step 1: depositing a transparent conductive layer on the external substrate, wherein the external substrate is a supporting structure of the perovskite cell; Step 2: preparing a hole transport layer on the transparent conductive layer; Step 3: preparing a self-assembled monolayer on the hole transport layer; Step 4: preparing a perovskite active layer on the self-assembled monolayer; Step 5: depositing an electron transport material on the perovskite active layer to form an electron transport layer; Step 6: preparing a hole blocking layer on the electron transport layer; Step seven: depositing a back electrode on the hole blocking layer.

5. The method for preparing a perovskite cell with a self-assembled monolayer according to claim 4, characterized in that: The specific steps of preparing the self-assembled monolayer on the hole transport layer include: Firstly, three mixed solvents of the ethanol and the isopropanol are prepared, namely solvent one, solvent two and solvent three; Then, Me-4PACz is added to solvent one to form solution one, and phosphorylcholine chloride is added to solvent two to form solution two; Then, the obtained solution 1 and solution 2 are added into the solvent 3, and are fully dissolved by magnetic stirring to obtain the precursor of the self-assembled monolayer.

6. The method for preparing a perovskite cell having a self-assembled monolayer according to claim 5, characterized in that: Add Me-4PACz with a concentration of 0.1-0.5 mg / mL to solvent 1; Add phosphorylcholine chloride with a dissolved concentration of 0.05-0.5 mg / mL to solvent 2; Then add the obtained solution one and solution two into solvent three, and fully dissolve them by magnetic stirring, and the molar ratio of Me-4PACz and phosphorylcholine chloride is 10:1~1:1, the volume ratio of the ethanol and the isopropanol in solvent three is 1:1~3:1, and the total concentration is controlled at 0.2~1.0 mg / mL, which is the precursor of the self-assembled monolayer.

7. The method for preparing a perovskite cell having a self-assembled monolayer according to claim 6, characterized in that: The precursor of the self-assembled monolayer is uniformly printed on the hole transport layer at a speed of 5-50 mm / s to form a self-assembled monolayer film.

8. The method for preparing a perovskite cell having a self-assembled monolayer according to claim 7, characterized in that: The self-assembled monomolecular film is formed and annealed at a temperature of 80-120 degrees Celsius for a time of 10-30 minutes to obtain the self-assembled monomolecular layer.

9. The method for preparing a perovskite cell with a self-assembled monolayer according to claim 8, characterized in that: The total thickness of the self-assembled monolayer is 1-5 nm.

10. The method for preparing a perovskite cell with a self-assembled monolayer according to claim 8, characterized in that: The self-assembled monolayer is prepared by coating, spin coating, self-assembly deposition or spray coating.

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