Perovskite cell prepared based on biomimetic mineralization principle and preparation method thereof

Abstract

The invention relates to a perovskite cell prepared based on a biomimetic mineralization principle and a preparation method thereof. The cell comprises a biomolecule template layer and a perovskite layer, and the material of the biomolecule template layer is selected from one or a mixture of more of polypeptide, protein and biomimetic polymer. The technical problem to be solved is how to provide a perovskite cell prepared based on the biomimetic mineralization principle, the cell is provided with a biomolecular template layer, the defect density and internal stress of a film can be reduced fundamentally, and the crystallization quality, the photoelectric conversion performance and the environmental adaptability of the perovskite cell are remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of perovskite battery technology, and in particular relates to a perovskite battery prepared based on the principle of biomimetic mineralization and its preparation method. Background Technology

[0002] Currently, solution methods are widely used and conventional in the preparation of perovskite thin films, including processes such as one-step spin coating, two-step spin coating, and doctor blade printing. These methods mostly rely on rapid annealing at high temperatures (>100°C) or on anti-solvent extraction crystallization to enable the perovskite precursor solution to complete the nucleation and growth process in a very short time.

[0003] However, this crystallization method has many significant drawbacks. The nucleation process is random and disordered, resulting in uneven grain size distribution and numerous grain boundaries, which in turn introduce a large number of defects. Rapid solvent evaporation and violent crystallization reactions can generate internal stress inside the film, causing pinholes, cracks, or phase separation, which seriously damages the film's density and uniformity. Moreover, high-temperature processing not only consumes a lot of energy but also limits its application on flexible substrates.

[0004] To improve crystal quality, existing technologies have proposed methods such as additives, solvent engineering, and interface modification. Although these methods can passivate defects and increase grain size to some extent, they do not change the inherent disordered growth of crystals, ultimately resulting in the electrical properties of the prepared products failing to reach ideal levels. Summary of the Invention

[0005] The main objective of this invention is to provide a perovskite battery prepared based on the principle of biomimetic mineralization and its preparation method. The technical problem to be solved is how to provide a perovskite battery prepared based on the principle of biomimetic mineralization. This battery, by setting a biomolecular template layer, can fundamentally reduce the defect density and internal stress of the thin film, and significantly improve the crystal quality, photoelectric conversion performance and environmental adaptability of the perovskite battery.

[0006] The objective of this invention and the technical problem it solves are achieved by the following technical solution. A perovskite battery prepared based on the principle of biomimetic mineralization, according to this invention, comprises a biomolecular template layer and a perovskite layer; the biomolecular template layer is made of one or more of peptides, proteins, and biomimetic polymers.

[0007] Preferably, in the aforementioned perovskite battery prepared based on the biomimetic mineralization principle, the biomolecular template layer is composed of polyethylene glycol blocks, oligomeric aspartic acid blocks, and perylene imide blocks connected sequentially; the structural formula of the biomolecular template layer is mPEG-b-(Asp). n -b-PDI; where n is an integer from 5 to 20.

[0008] Preferably, in the aforementioned perovskite battery prepared based on the biomimetic mineralization principle, n is 12.

[0009] Preferably, in the aforementioned perovskite battery prepared based on the biomimetic mineralization principle, the polyethylene glycol block is made of monomethoxy polyethylene glycol; the molecular weight of the monomethoxy polyethylene glycol is 1000; the perylene imide block is made of a perylene imide derivative; the perylene imide derivative has a carboxyl group at one end and an acid anhydride at the other end.

[0010] Preferably, the aforementioned perovskite battery prepared based on the biomimetic mineralization principle comprises, from bottom to top, a substrate, a hole transport layer, a biomolecular template layer, a perovskite layer, an electron transport layer, an intermediate connecting layer, and an electrode.

[0011] The objective of this invention and the technical problem it solves are further achieved by the following technical solution. A method for preparing a perovskite solar cell based on the principle of biomimetic mineralization, according to this invention, includes: 1) A hole transport layer is prepared on a substrate, and then a biomolecular template layer is prepared on the hole transport layer; 2) A perovskite precursor solution is dropped onto the biomolecular template layer to carry out a biomimetic mineralization reaction. After the reaction is completed, the perovskite layer is obtained. The material of the biomolecular template layer is selected from one or more of peptides, proteins, and biomimetic polymers. 3) Then, an electron transport layer, an intermediate connection layer, and an electrode are sequentially prepared on the perovskite layer to obtain the perovskite battery prepared based on the biomimetic mineralization principle.

[0012] Preferably, in the aforementioned method for preparing perovskite solar cells based on the principle of biomimetic mineralization, step 1) specifically involves the following method: 1.1) Fabricate a hole transport layer on a substrate; 1.2) Prepare a biomolecular template solution, then drop the biomolecular template layer solution onto the hole transport layer, and then let it stand in an environment with a humidity of 40-70% to obtain the biomolecular template layer.

[0013] Preferably, in the aforementioned method for preparing perovskite solar cells based on the principle of biomimetic mineralization, the method for preparing the biomolecular template layer solution includes: 1) Preparation of macromolecular initiator mPEG 1000 -NH2: Monomethoxy polyethylene glycol was dissolved in anhydrous dichloromethane and cooled. Triethylamine and p-toluenesulfonyl chloride were added sequentially under an inert atmosphere, and the reaction was carried out at 0°C for 2 hours. The reaction was then continued at room temperature for 12 hours. After the reaction was completed, the mixture was washed and filtered to obtain the mPEG.1000 -Ots; 2) mPEG 1000 -Terminal amination of Ots: The obtained mPEG 1000 -Ots were dissolved in ammonia water, heated and sealed for reaction, and after the reaction was completed, cooled, precipitated, filtered, washed, and dried to obtain terminally aminated mPEG. 1000 -NH2; 3) Peptide block NCA ring-opening polymerization: The β-benzyl-L-aspartic acid ester N-carboxylic acid anhydride monomer is reacted with the terminally aminated mPEG. 1000 -NH2, dissolved in solvent A under an inert atmosphere, was stirred to initiate the reaction. After the reaction was complete, the precipitate was collected, centrifuged, washed, and dried to obtain the diblock copolymer mPEG. 1000 -b-PBLA; 4) Perylene imide end-group functionalization: The prepared diblock copolymer mPEG 1000 -b-PBLA and the perylene imide derivative were dissolved in solvent A, and then a condensing agent was added. The reaction was carried out in an inert and light-protected environment. After the reaction was completed, the precipitate was collected, centrifuged, washed, and dried to obtain the triblock precursor mPEG. 1000 -b-PBLA-b-PDI; 5) Sidechain protection and passivation: The triblock precursor mPEG 1000 -b-PBLA-b-PDI was dissolved in dichloromethane, cooled, and then trifluoroacetic acid and triisopropylsilane were added. The reaction was first carried out at 0°C, and then at room temperature. After the reaction was completed, the mixture was heated, precipitated, centrifuged, and filtered to obtain a biomolecular template layer solution.

[0014] Preferably, in the aforementioned method for preparing perovskite solar cells based on the biomimetic mineralization principle, the condensing agent is 4-dimethylaminopyridine and N,N'-diisopropylcarbodiimide; in steps 3) and 4), the solvent A is anhydrous N,N-dimethylformamide.

[0015] Preferably, in the aforementioned method for preparing perovskite solar cells based on the principle of biomimetic mineralization, step 2) specifically involves the following method: The perovskite precursor solution is dropped onto the biomolecular template layer, and then reacted in a closed environment with a relative humidity of 55-65% to begin crystallization. After crystallization is completed, the perovskite layer is obtained.

[0016] By employing the above technical solution, the perovskite battery and its preparation method based on the biomimetic mineralization principle proposed in this invention have at least the following advantages: This invention proposes a perovskite solar cell fabricated based on the principle of biomimetic mineralization. This cell utilizes a biomolecular template as a guide to achieve an ordered and controllable epitaxial growth process of perovskite crystals. This method can fundamentally reduce the defect density and internal stress of the thin film, significantly improving its crystal quality, photoelectric conversion performance, and environmental adaptability. Simultaneously, this technology effectively overcomes the drawbacks of traditional fabrication processes, such as high energy consumption, the use of highly toxic substances, and incompatibility with flexible substrates, opening up a low-cost and environmentally friendly new manufacturing path for developing high-performance, high-stability perovskite optoelectronic devices.

[0017] This invention discloses a method for preparing perovskite thin films based on the principle of biomimetic mineralization. The process is simple, the reaction conditions are mild and easily controllable, and the performance is stable and reliable under repeated operation. This method is not only perfectly suited to the research and development needs of small-sized substrates in a laboratory environment, but its underlying technical principles also possess strong potential for large-scale scalability, laying a solid foundation for future large-scale production.

[0018] In terms of process compatibility, this method can seamlessly integrate with various large-area deposition processes such as slot coating, blade coating, and spray coating. Its core mechanism lies in the fact that the biomolecular template can precisely guide ordered nucleation at the gas-liquid interface and achieve efficient in-situ passivation at grain boundaries. This key mechanism remains highly efficient and stable throughout the large-area preparation process, ensuring the uniformity of film quality. Furthermore, this biomimetic mineralization process exhibits strong adaptability to post-processing conditions such as annealing temperature and ambient atmosphere. It can efficiently complete the crystallization and template removal processes within a wide temperature range of 80–120°C, without relying on harsh inert atmospheres or precise temperature control. This characteristic greatly simplifies the process flow, reduces equipment costs, and allows it to be easily integrated into continuous production systems such as roll-to-roll (R2R) or sheet-to-sheet (S2S), demonstrating extremely broad prospects for industrial application.

[0019] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Attached Figure Description

[0020] Figure 1 These are XRD diagrams of the perovskite films of Example 3 and Comparative Example 1 of the present invention. Figure 2 The TRPL test results are for the perovskite films of Example 3 and Comparative Example 1 of this invention. Figure 3 The JV curves of the perovskite solar cells of Example 3 and Comparative Example 1 of this invention are shown. Figure 4The JV characteristic curves and maximum power point tracking (MPPT) steady-state output performance diagrams of the perovskite solar cells of Example 3 and Comparative Example 1 of this invention were measured under standard illumination conditions (AM 1.5G, 100mW / cm²). Detailed Implementation

[0021] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a perovskite battery prepared based on the biomimetic mineralization principle according to the present invention. In the following description, different "embodiments" or "embodiments" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable manner.

[0022] This invention proposes a perovskite battery based on the principle of biomimetic mineralization, which includes a biomolecular template layer and a perovskite layer; the biomolecular template layer is made of one or more of peptides, proteins and biomimetic polymers.

[0023] This invention discloses a biomolecular template layer material with carboxyl, amino, or thiol functional groups on its molecular chain. In a solution environment, these functional groups can spontaneously assemble into a biomolecular template with an ordered nanostructure through intermolecular forces. This biomolecular template guides the biomimetic mineralization growth of perovskite crystals under mild conditions, thereby achieving precise control over the entire process from the ordered adsorption of precursor ions to crystal epitaxial nucleation. Specific advantages are reflected in the following aspects: 1. Significantly improved crystal quality: The prepared thin film exhibits a highly consistent <100> crystal plane preferred orientation, with significantly increased and uniformly distributed grain size and a marked reduction in the number of grain boundaries, which essentially reduces the density of nonradiative recombination centers.

[0024] In perovskite crystal structures, charge mobility is often highest in the <100> crystal orientation. When grains are uniformly aligned perpendicular to the electrode in this orientation, a "fast channel" for efficient charge transport from the interior of the thin film to the electrode is created, significantly reducing the probability of charge being trapped and lost at disordered grain boundaries. This structural characteristic directly promotes the extension of carrier lifetime and the increase of diffusion length.

[0025] Furthermore, randomly oriented grains, upon contact, form complex and high-energy grain boundary regions, which become the primary sites of charge recombination (i.e., energy loss). In contrast, through a highly consistent orientation growth strategy, grains can be more tightly and smoothly "stitched" together, forming larger and more uniformly distributed grain structures. This transformation effectively reduces the total number of grain boundaries and lowers the defect density in the material, thereby directly improving the open-circuit voltage (VOC) and fill factor (FF) of perovskite solar cells, providing crucial support for the overall optimization of device performance.

[0026] 2. Excellent carrier performance: Time-resolved fluorescence spectroscopy (TRPL) results show that the carrier lifetime of the film exceeds 3 μs, which is far superior to the film prepared by traditional methods (usually less than 1 μs); the carrier diffusion length measured by transient photovoltage decay exceeds 5 μm, indicating that the film prepared by this invention has excellent carrier transport and collection capabilities, laying the foundation for the preparation of high-efficiency thick film devices.

[0027] 3. Breakthrough in photoelectric conversion efficiency: The perovskite solar cell with formal (nip) structure fabricated based on this thin film has a photoelectric conversion efficiency (PCE) that is stable at over 24.5%, a fill factor (FF) that exceeds 82%, and a significant improvement in open-circuit voltage (VOC).

[0028] 4. Significantly enhanced stability: After being left to stand in an air environment at room temperature and 30-50% relative humidity for 1000 hours, the unpackaged device can still maintain more than 95% of its initial efficiency; after operating under continuous standard illumination with maximum power point tracking (MPP) for 1000 hours, the efficiency degradation rate is less than 5%.

[0029] 5. Good fabrication consistency and scalability: This method effectively overcomes the problems of pinholes and uneven film coverage commonly found in traditional processes. The film thickness deviation on substrates with a maximum size of 5cm×5cm is less than ±3%, and the efficiency standard deviation of devices in the same batch is less than 0.3%, which significantly improves the reliability of the process and its application potential in large-scale production.

[0030] The perovskite layer disclosed in this invention is obtained from a perovskite precursor solution, the raw materials of which include: a lead source compound and an organic ammonium salt; the lead source compound is selected from one or more of lead iodide, lead bromide and lead chloride; the organic ammonium salt is selected from one or more of formamidinium iodide, methylamine iodide and cesium iodide.

[0031] Preferably, in the aforementioned perovskite battery prepared based on the biomimetic mineralization principle, the biomolecular template layer is composed of polyethylene glycol blocks, oligomeric aspartic acid blocks, and perylene imide blocks connected sequentially; the structural formula of the biomolecular template layer is mPEG-b-(Asp).n -b-PDI; where n is an integer from 5 to 20.

[0032] This invention discloses a raw material for a biomolecular template layer, which is composed of polyethylene glycol blocks, oligomeric aspartic acid blocks, and perylene imide blocks linked sequentially, with the structural formula: mPEG-b-(Asp). n -b-PDI; where mPEG is a polyethylene glycol block; (Asp) n For oligoaspartic acid blocks; PDI for perylene imide blocks; n is an integer from 5 to 20, representing the presence of 5 to 20 oligoaspartic acid blocks.

[0033] Preferably, in the aforementioned perovskite battery prepared based on the biomimetic mineralization principle, n is 12.

[0034] Preferably, in the aforementioned perovskite battery prepared based on the biomimetic mineralization principle, the polyethylene glycol block is made of monomethoxy polyethylene glycol; the molecular weight of the monomethoxy polyethylene glycol is 1000; the perylene imide block is made of a perylene imide derivative; the perylene imide derivative has a carboxyl group at one end and an acid anhydride at the other end.

[0035] In this invention, the mPEG block effectively improves the water solubility of the system and inhibits excessive growth of perovskite grains; the (Asp) n Blocks, through their carboxyl functional groups, achieve selective capture of lead ions (Pb²⁺); while the PDI blocks, on the one hand, interact with organic ammonium ions through π-conjugated structures, guiding their orderly arrangement, and on the other hand, through self-assembly properties, form highly ordered nanowire or nanoribbon templates, thereby achieving directional epitaxial growth of perovskite crystals and effective control of defects at the molecular scale.

[0036] This invention discloses the use of monomethoxy polyethylene glycol with a molecular weight of 1000 as the raw material for polyethylene glycol blocks; therefore, the structural formula of the biomolecular template layer is mPEG. 1000 -b-(Asp) n -b-PDI.

[0037] Preferably, the aforementioned perovskite battery prepared based on the biomimetic mineralization principle comprises, from bottom to top, a substrate, a hole transport layer, a biomolecular template layer, a perovskite layer, an electron transport layer, an intermediate connecting layer, and an electrode.

[0038] This invention discloses the basic structure of a battery, wherein the biomolecular template layer has a thickness of 1–5 nm, the perovskite layer has a thickness of 450 nm, the electron transport layer is made of fullerene (C60) with a thickness of 20–25 nm, and the intermediate connecting layer is made of copper bath (BCP) with a thickness of 5–7 nm. Notably, the biomolecular template layer disclosed in this invention is ultrathin, with a thickness of only 1–5 nm, effectively enabling hole tunneling.

[0039] This invention also proposes a method for preparing a perovskite solar cell based on the principle of biomimetic mineralization, the method comprising: 1) A hole transport layer is prepared on a substrate, and then a biomolecular template layer is prepared on the hole transport layer; 2) A perovskite precursor solution is dropped onto the biomolecular template layer to carry out a biomimetic mineralization reaction. After the reaction is completed, the perovskite layer is obtained. The material of the biomolecular template layer is selected from one or more of peptides, proteins, and biomimetic polymers. 3) Then, an electron transport layer, an intermediate connection layer, and an electrode are sequentially prepared on the perovskite layer to obtain the perovskite battery prepared based on the biomimetic mineralization principle.

[0040] Preferably, in the aforementioned method for preparing perovskite solar cells based on the principle of biomimetic mineralization, in step 2), the method for preparing the perovskite precursor solution is as follows: Lead iodide, formamidinium iodide, and cesium iodide were dissolved in γ-valerol solvent, and then stirred at 60°C for 4 hours in a nitrogen-filled environment to obtain a clear perovskite precursor solution.

[0041] Preferably, in the aforementioned method for preparing perovskite solar cells based on the principle of biomimetic mineralization, step 1) specifically involves the following method: 1.1) Fabricate a hole transport layer on a substrate; 1.2) Prepare a biomolecular template solution, then drop the biomolecular template layer solution onto the hole transport layer, and then let it stand in an environment with a humidity of 40-70% to obtain the biomolecular template layer.

[0042] Preferably, in the aforementioned method for preparing perovskite solar cells based on the principle of biomimetic mineralization, the method for preparing the biomolecular template layer solution includes: 1) Preparation of macromolecular initiator mPEG 1000 -NH2: Monomethoxy polyethylene glycol was dissolved in anhydrous dichloromethane and cooled. Triethylamine and p-toluenesulfonyl chloride were added sequentially under an inert atmosphere, and the reaction was carried out at 0°C for 2 hours. The reaction was then continued at room temperature for 12 hours. After the reaction was completed, the mixture was washed and filtered to obtain the mPEG. 1000 -Ots; 2) mPEG 1000 -Terminal amination of Ots: The obtained mPEG 1000 -Ots were dissolved in ammonia water, heated and sealed for reaction, and after the reaction was completed, cooled, precipitated, filtered, washed, and dried to obtain terminally aminated mPEG. 1000 -NH2; 3) Peptide block NCA ring-opening polymerization: The β-benzyl-L-aspartic acid ester N-carboxylic acid anhydride monomer is reacted with the terminally aminated mPEG. 1000 -NH2, dissolved in solvent A under an inert atmosphere, was stirred to initiate the reaction. After the reaction was complete, the precipitate was collected, centrifuged, washed, and dried to obtain the diblock copolymer mPEG. 1000 -b-PBLA; 4) Perylene imide end-group functionalization: The prepared diblock copolymer mPEG 1000 -b-PBLA and the perylene imide derivative were dissolved in solvent A, and then a condensing agent was added. The reaction was carried out in an inert and light-protected environment. After the reaction was completed, the precipitate was collected, centrifuged, washed, and dried to obtain the triblock precursor mPEG. 1000 -b-PBLA-b-PDI; 5) Sidechain protection and passivation: The triblock precursor mPEG 1000 -b-PBLA-b-PDI was dissolved in dichloromethane, cooled, and then trifluoroacetic acid and triisopropylsilane were added. The reaction was first carried out at 0°C, and then at room temperature. After the reaction was completed, the mixture was heated, precipitated, centrifuged, and filtered to obtain a biomolecular template layer solution.

[0043] Preferably, in the aforementioned method for preparing perovskite solar cells based on the biomimetic mineralization principle, the condensing agent is 4-dimethylaminopyridine and N,N'-diisopropylcarbodiimide; in steps 3) and 4), the solvent A is anhydrous N,N-dimethylformamide.

[0044] Preferably, in the aforementioned method for preparing perovskite solar cells based on the principle of biomimetic mineralization, step 2) specifically involves the following method: The perovskite precursor solution is dropped onto the biomolecular template layer, and then reacted in a closed environment with a relative humidity of 55-65% to begin crystallization. After crystallization is completed, the perovskite layer is obtained.

[0045] This invention discloses a method for preparing perovskite solar cells based on the principle of biomimetic mineralization. The core steps involve the preparation of a biomolecular template layer and the biomimetic mineralization reaction. Specifically: The biomolecular template layer is made from a biomolecular template layer solution. This invention discloses a specific method for preparing the biomolecular template layer solution, as follows: 1) Preparation of macromolecular initiator mPEG 1000 -NH2: Monomethoxy polyethylene glycol (mPEG-OH) was dissolved in anhydrous dichloromethane. Under ice-water bath cooling and nitrogen protection, triethylamine and p-toluenesulfonyl chloride were added sequentially, and the reaction was carried out at 0°C for 2 hours. The reaction was then continued at room temperature for 12 hours. After the reaction was complete, the mixture was washed three times with ice water. The organic phase was dried over anhydrous sodium sulfate, filtered, and the solvent was removed by rotary evaporation after filtration to obtain a white, waxy mPEG. 1000 -OTs; 2) Terminal amination of mPEG-Ots: The obtained mPEG 1000 -OTs were dissolved in concentrated ammonia solution and reacted under sealed conditions at 60°C for 24 hours. After the reaction was completed, the solution was cooled and then transferred to cold diethyl ether to precipitate. The white solid was collected by filtration, washed three times with diethyl ether, and dried under vacuum to obtain terminally aminated mPEG. 1000 -NH2; 3) Peptide block NCA ring-opening polymerization: The β-benzyl-L-aspartic acid ester N-carboxylic acid anhydride (BLA-NCA) monomer was reacted with the prepared terminally aminated mPEG. 1000 -NH2 and other compounds were placed together in a dry reaction flask and then dissolved in anhydrous N,N-dimethylformamide (DMF) solvent under high-purity nitrogen protection. The reaction was carried out with continuous stirring at 25°C for 72 h. The ring-opening polymerization of BLA-NCA was initiated by the terminal amino group of mPEG-NH2. After the reaction was completed, the reaction solution was poured into excess ice-cold diethyl ether to precipitate the product. The white solid product was collected by centrifugation, washed three times with diethyl ether, and dried under vacuum to obtain the diblock copolymer mPEG. 1000 -b-PBLA; 4) Perylene imide end-group functionalization: The prepared diblock copolymer mPEG 1000 -b-PBLA and a perylene diimide derivative (PDI-COOH) with a carboxyl group at one end and an anhydride functionalization at the other end were dissolved in anhydrous N,N-dimethylformamide (DMF). Then, condensing agents (4-dimethylaminopyridine (DMAP) and N,N'-diisopropylcarbodiimide (DIC)) were added, and the mixture was reacted at 30°C for 24 h under nitrogen protection and in the dark. After the reaction was complete, the reaction solution was precipitated in ice-cold diethyl ether. The dark red solid was collected by centrifugation and thoroughly washed with diethyl ether to obtain the triblock precursor mPEG. 1000 -b-PBLA-b-PDI; 5) Sidechain protection and passivation: The obtained triblock precursor mPEG 1000 -b-PBLA-b-PDI was dissolved in dichloromethane, and then a mixture of trifluoroacetic acid and triisopropylsilane was slowly added under ice-water bath cooling. The reaction was carried out at 0°C for 2 hours, then at room temperature for another 6 hours to remove the benzyl protecting group from the aspartic ester side chain. After the reaction, most of the solvent was removed by rotary evaporation, and the residue was precipitated in ice-cold ether. The solid was collected by centrifugation and then redissolved in ultrapure water. Dialysis was performed using a dialysis bag with a molecular weight cutoff of 3500 Da against deionized water for 48 hours. After freeze-drying, a biomolecular template solution with the structural formula mPEG was obtained. 1000 -b-(Asp) 12 -b-PDI.

[0046] Preparation of biomolecular template layers using biomolecular template layer solutions: 1) Dissolve the prepared biomolecular template layer solution in a solvent (a mixed solvent composed of ultrapure water and anhydrous ethanol in a volume ratio of 7:3), then heat in a water bath at a temperature of 25–50°C, followed by magnetic stirring at 500 rpm for 4–12 h until completely dissolved, forming a homogeneous and clear solution for later use; the concentration of the solution is 0.1–2.0 mg / mL; 2) Spin-coat the solution onto the hole transport layer at 3000 rpm, and then let it stand for 2 hours in an environment with a relative humidity of 40-70% and a temperature of 25°C, so that the biomolecules can self-assemble into an ordered nanostructure biomolecular template layer through intermolecular forces.

[0047] Biomimetic mineralization reaction: The perovskite precursor solution was dropped onto the surface of the biomolecular template layer and reacted in a closed environment at 10–50 °C and 60% relative humidity for 12–72 h to complete the epitaxial growth of the perovskite crystals and the biomimetic mineralization reaction, thus obtaining the perovskite layer.

[0048] The present invention will be further described below with reference to specific embodiments, but this should not be construed as a limitation on the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention still fall within the scope of protection of the present invention.

[0049] Unless otherwise specified, all materials and reagents mentioned below are commercially available products well known to those skilled in the art; unless otherwise specified, all methods described are methods known in the art. Unless otherwise defined, the technical or scientific terms used should have the ordinary meaning understood by those skilled in the art to which this invention pertains.

[0050] Example 1 A method for preparing a biomolecular template layer solution is as follows: 1) Preparation of macromolecular initiator mPEG 1000 -NH2: 10 g of monomethoxy polyethylene glycol (mPEG-OH) with a molecular weight of 1000 was dissolved in 100 mL of anhydrous dichloromethane. Under ice-water bath cooling and nitrogen protection, 2 mL of triethylamine and 1.5 g of p-toluenesulfonyl chloride were added sequentially. The reaction was carried out at 0 °C for 2 h, and then the temperature was raised to room temperature and the reaction was continued for 12 h. After the reaction was completed, the mixture was washed three times with ice water. The organic phase was dried with anhydrous sodium sulfate, filtered, and the solvent was removed by rotary evaporation after filtration to obtain a white waxy mPEG. 1000 -OTs; 2) Terminal amination of mPEG-Ots: The obtained mPEG 1000 -OTs were dissolved in 100 mL of concentrated ammonia solution and reacted under sealed conditions at 60 °C for 24 h. After the reaction was completed, the solution was cooled and then transferred to cold diethyl ether to precipitate. The white solid was collected by filtration, washed three times with diethyl ether, and dried under vacuum to obtain terminally aminated mPEG. 1000 -NH2; 3) Peptide block NCA ring-opening polymerization: 2g of β-benzyl-L-aspartic acid ester N-carboxylic acid anhydride (BLA-NCA) monomer was reacted with 2g of the terminally aminated mPEG obtained therefrom. 1000 -NH2 and other compounds were placed together in a dry reaction flask and then dissolved in 40 mL of anhydrous N,N-dimethylformamide (DMF) under high-purity nitrogen protection. The mixture was stirred continuously at 25 °C for 72 h. The ring-opening polymerization of BLA-NCA was initiated by the terminal amino group of mPEG-NH2. After the reaction was completed, the reaction solution was poured into excess ice-cold diethyl ether to precipitate the product. The white solid product was collected by centrifugation, washed three times with diethyl ether, and dried under vacuum to obtain the diblock copolymer mPEG. 1000 -b-PBLA; 4) Perylene imide end-group functionalization: The 1g of the prepared diblock copolymer mPEG 1000 -b-PBLA and 0.3g of a perylene diimide derivative (PDI-COOH) with a carboxyl group at one end and an anhydride functionalized end at the other were dissolved in 30mL of anhydrous N,N-dimethylformamide (DMF). Then, 0.1g of condensing agents (4-dimethylaminopyridine (DMAP) and N,N'-diisopropylcarbodiimide (DIC)) were added. The reaction was carried out at 30°C for 24h under nitrogen protection and in the dark. After the reaction was completed, the reaction solution was precipitated in ice-cold diethyl ether. The dark red solid was collected by centrifugation and washed thoroughly with diethyl ether to obtain the triblock precursor mPEG. 1000-b-PBLA-b-PDI; 5) Sidechain protection and passivation: The obtained 1g of the triblock precursor mPEG 1000 -b-PBLA-b-PDI was dissolved in 20 mL of dichloromethane. Then, under ice-water bath cooling, a mixture of 10 mL of trifluoroacetic acid and 2 mL of triisopropylsilane was slowly added. The reaction was carried out at 0°C for 2 hours, then at room temperature for another 6 hours to remove the benzyl protecting group from the aspartic acid ester side chain. After the reaction, most of the solvent was removed by rotary evaporation. The residue was precipitated in ice-cold ether, and the solid was collected by centrifugation. The solid was then redissolved in ultrapure water and dialyzed against deionized water for 48 hours using a dialysis bag with a molecular weight cutoff of 3500 Da. After freeze-drying, a biomolecular template solution with the structural formula mPEG was obtained. 1000 -b-(Asp) 12 -b-PDI.

[0051] Example 2 A perovskite precursor solution, the preparation method of which is as follows: Weigh 461 mg lead iodide (PbI2), 172 mg formamidinium iodide (FAI) and 25.9 mg cesium iodide (CsI), dissolve them in 1 mL γ-valerolactone, and stir for 4 h under nitrogen protection at 60 °C to obtain a clear and transparent precursor solution with a concentration of 1.3 M.

[0052] Example 3 A perovskite solar cell based on the principle of biomimetic mineralization is prepared by means of: 1) Mix 7 mL of ultrapure water with 3 mL of anhydrous ethanol to obtain a mixed solvent (water:ethanol ratio of 7:3 (v / v)). Then, dissolve 20 mg of mPEG1000-b-(Asp)12-b-PDI prepared in Example 1 in the mixed solvent. Stir magnetically in a constant temperature water bath at 40°C at a stirring speed of 500 rpm for 6 h until completely dissolved. Set aside for later use. 2) Take an FTO conductive glass substrate with a size of 2.5cm×2.5cm, and clean it by ultrasonic cleaning with acetone, isopropanol, ethanol and deionized water for 15min each, then dry it with nitrogen and treat it with ultraviolet ozone for 20min. 3) NiO is prepared on a treated FTO conductive glass substrate by magnetron sputtering or spin coating. x Hole transport layer; 4) Take 100 μL of the mixed solution prepared in step 1) and drop it onto the surface of the NiOx hole transport layer. Spin coat it at 3000 rpm for 30 s. Then transfer the spin-coated substrate to a constant temperature and humidity chamber and let it stand for 2 h at 25℃ and 50% relative humidity to form a uniform nanofiber biomolecular template layer. 5) Slowly drop 100 μL of the perovskite precursor liquid prepared in Example 2 onto the surface of the FTO substrate covered with the biomolecular template layer. Then place the sample horizontally in a sealed crystallization dish and transfer the crystallization dish to a constant temperature oven. React at 30°C for 36 hours to complete the epitaxial growth of perovskite crystals along the template structure and obtain the perovskite layer. 6) Finally, using conventional techniques, an electron transport layer, an intermediate connection layer, and an electrode are sequentially prepared on the surface of the perovskite layer to obtain a perovskite battery based on the biomimetic mineralization principle.

[0053] Example 4 Compared to Example 3, the concentration of the biomolecular template solution in Example 4 was 5 mg / mL.

[0054] Example 5 Compared with Example 3, the biomimetic mineralization crystallization process in Example 4 was carried out at a temperature of 50°C for 36 hours.

[0055] Comparative Example 1 Compared with Example 3, Comparative Example 1 does not have a biomolecular template layer.

[0056] The products obtained in Example 3 and Comparative Example 1 were subjected to electrical performance tests, and the results are as follows: like Figure 1 As shown, diamine molecules can spontaneously assemble on the surface of perovskite films, forming uniformly distributed nucleation templates. These templates induce the orderly growth of perovskite crystals from top to bottom. This process effectively suppresses random nucleation in the bulk phase, successfully enabling the fabrication of large-size, low-defect perovskite films.

[0057] from Figure 1 As can be clearly seen, both the perovskite films of Example 3 and Comparative Example 1 exhibited distinct diffraction peaks at 14.1°, 28.3°, and 31.8°. These diffraction peaks correspond to the perovskite α-phase FAPbI, respectively. 3- The (100), (200) and (210) crystal planes fully demonstrate that both preparation methods successfully formed the perovskite crystal structure.

[0058] Further analysis revealed a significant enhancement in the diffraction peak intensity of the perovskite film prepared in Example 3. Specifically, the full width at half maximum (FWHM) of the (100) crystal plane main peak was reduced by approximately 30% compared to Comparative Example 1, indicating that the perovskite film of Example 3 possesses better crystallinity and a larger grain size. More importantly, no obvious δ phase (a non-photoactive phase) was observed in the XRD pattern of Example 3. θ ≈11.7°) or PbI2 residue (2 θThe characteristic diffraction peaks were approximately 12.6°. This result indicates that the biomimetic mineralization process effectively suppressed the formation of non-photoactive impurity phases, successfully obtaining perovskite films with high phase purity. Furthermore, the (100) peak intensity of the perovskite film in Example 3 far exceeded that of other crystal planes, exhibiting strong preferred orientation, which is highly consistent with the biomimetic template-induced epitaxial growth mechanism.

[0059] pass Figure 2 As can be seen, the carrier dynamics of the thin film were analyzed using time-resolved fluorescence spectroscopy (TRPL). The perovskite thin film prepared using a biomimetic mineralization strategy (i.e., Example 3) exhibits excellent carrier lifetime performance, showing a significant lifetime extension characteristic, and its fluorescence decay curve can be fitted by a double exponential function. The average carrier lifetime (τ_avg) of Example 3 is as high as 380 ns, while the average carrier lifetime of the thin film prepared using the conventional method in Comparative Example 1 is only 137 ns, demonstrating that Example 3 far exceeds Comparative Example 1.

[0060] This result clearly demonstrates that the biomimetic mineralization process based on biomolecular templates effectively suppresses nonradiative recombination channels in the thin film. The significant improvement in carrier lifetime is mainly attributed to the following mechanisms: 1. The regular and ordered nucleation sites provided by the biological template guide the epitaxial growth of the crystal, resulting in a high-quality thin film with larger grain size and fewer grain boundaries, which greatly reduces the recombination rate at the grain boundaries; 2. During the crystallization process, the functional groups such as carboxyl and amino groups on the template molecular chain interact with the perovskite components, effectively passivating uncoordinated Pb²⁺ defects and halogen vacancies, and significantly reducing the number of trap-assisted recombination centers.

[0061] The extended carrier lifetime and improved diffusion efficiency mean that photogenerated carriers can be collected by the electrodes more efficiently. This change provides a crucial guarantee for the device to obtain higher open-circuit voltage and fill factor, fully demonstrating the significant advantages of biomimetic mineralization strategies in optimizing the photoelectric properties of perovskite thin films.

[0062] Furthermore, such as Figure 2 As shown, the perovskite film synergistically regulated by diamines exhibits a significantly improved surface morphology, as observed by scanning electron microscopy (SEM). Compared to Comparative Example 1, the content of unreacted lead iodide (PbI2) in the film is substantially reduced, indicating a more complete and thorough crystallization process. Simultaneously, the perovskite grain size is significantly increased, and the number of grain boundaries is noticeably reduced. Furthermore, the passivation material is selectively distributed in the grain boundary regions, forming an effective passivation layer structure. This unique morphological characteristic strongly demonstrates the synergistic effect of diamine molecules in regulating crystallization kinetics and defect passivation, contributing to improved performance and stability of perovskite optoelectronic devices.

[0063] pass Figure 3 It can be seen that the perovskite solar cell prepared using biomimetic mineralization control exhibits a significant improvement in photoelectric conversion efficiency, as shown in its current density-voltage (J-V) characteristics. Compared to Comparative Example 1, the device in Example 3, after biomimetic mineralization treatment, shows significant improvements in open-circuit voltage (V_OC), short-circuit current density (J_SC), and fill factor (FF) (detailed data are shown in Table 1), ultimately achieving a higher conversion efficiency. This experimental result demonstrates that biomimetic mineralization plays an excellent role in synergistic passivation and crystallization control in optimizing thin film quality, reducing non-radiative recombination losses, and promoting effective charge extraction.

[0064] Table 1. Efficiency of perovskite solar cells based on biomimetic mineralization regulation In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0065] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A perovskite solar cell based on the principle of biomimetic mineralization, characterized in that, It includes a biomolecular template layer and a perovskite layer; the biomolecular template layer is made of one or more of peptides, proteins and biomimetic polymers.

2. The perovskite solar cell based on the biomimetic mineralization principle according to claim 1, characterized in that, The biomolecular template layer is composed of polyethylene glycol blocks, oligoaspartic acid blocks, and perylene imide blocks linked sequentially; the structural formula of the biomolecular template layer is mPEG-b-(Asp). n -b-PDI; where n is an integer from 5 to 20.

3. The perovskite battery prepared based on the biomimetic mineralization principle according to claim 2, characterized in that, The value of n is 12.

4. The perovskite battery prepared based on the biomimetic mineralization principle according to claim 2, characterized in that, The polyethylene glycol block is made of monomethoxy polyethylene glycol; the molecular weight of the monomethoxy polyethylene glycol is 1000; the perylene imide block is made of a perylene imide derivative; the perylene imide derivative has a carboxyl group at one end and an acid anhydride at the other end.

5. The perovskite solar cell based on the biomimetic mineralization principle according to claim 1, characterized in that, The battery comprises, from bottom to top, a substrate, a hole transport layer, a biomolecular template layer, a perovskite layer, an electron transport layer, an intermediate connecting layer, and an electrode.

6. A method for preparing a perovskite solar cell based on the principle of biomimetic mineralization, characterized in that, The method includes: 1) A hole transport layer is prepared on a substrate, and then a biomolecular template layer is prepared on the hole transport layer; 2) A perovskite precursor solution is dropped onto the biomolecular template layer to carry out a biomimetic mineralization reaction. After the reaction is completed, a perovskite layer is obtained. The material of the biomolecular template layer is selected from one or more of peptides, proteins, and biomimetic polymers. 3) Then, an electron transport layer, an intermediate connection layer, and an electrode are sequentially prepared on the perovskite layer to obtain the perovskite battery prepared based on the biomimetic mineralization principle.

7. The method for preparing a perovskite solar cell based on the biomimetic mineralization principle according to claim 6, characterized in that, The specific method for step 1) is as follows: 1.1) Fabricate a hole transport layer on a substrate; 1.2) Prepare a biomolecular template solution, then drop the biomolecular template layer solution onto the hole transport layer, and then let it stand in an environment with a humidity of 40-70% to obtain the biomolecular template layer.

8. The method for preparing a perovskite solar cell based on the biomimetic mineralization principle according to claim 7, characterized in that, The method for preparing the biomolecular template layer solution includes: 1) Preparation of macromolecular initiator mPEG 1000 -NH2: Monomethoxy polyethylene glycol was dissolved in anhydrous dichloromethane and cooled. Triethylamine and p-toluenesulfonyl chloride were added sequentially under an inert atmosphere, and the reaction was carried out at 0°C for 2 h. Then, the reaction was continued at room temperature for 12 h. After the reaction was completed, the mixture was washed and filtered to obtain mPEG. 1000 -Ots; 2) mPEG 1000 -Terminal amination of Ots: The obtained mPEG 1000 -Ots were dissolved in ammonia water, heated and sealed for reaction, and after the reaction was completed, cooled, precipitated, filtered, washed, and dried to obtain terminally aminated mPEG. 1000 -NH2; 3) Peptide block NCA ring-opening polymerization: The β-benzyl-L-aspartic acid ester N-carboxylic acid anhydride monomer is reacted with the terminally aminated mPEG. 1000 -NH2 was dissolved in solvent A under an inert atmosphere, stirred, and the reaction began. After the reaction was completed, the precipitate was collected, centrifuged, washed, and dried to obtain the diblock copolymer mPEG. 1000 -b-PBLA; 4) Perylene imide end-group functionalization: The prepared diblock copolymer mPEG 1000 -b-PBLA and perylene imide derivatives were dissolved in solvent A, and then a condensing agent was added. The reaction was carried out in an inert and light-protected environment. After the reaction was completed, the precipitate was collected, centrifuged, washed, and dried to obtain the triblock precursor mPEG. 1000 -b-PBLA-b-PDI; 5) Sidechain protection and passivation: The triblock precursor mPEG 1000 -b-PBLA-b-PDI was dissolved in dichloromethane, cooled, and then trifluoroacetic acid and triisopropylsilane were added. The reaction was first carried out at 0°C, and then at room temperature. After the reaction was completed, the mixture was heated, precipitated, centrifuged, and filtered to obtain a biomolecular template layer solution.

9. The method for preparing a perovskite solar cell based on the biomimetic mineralization principle according to claim 8, characterized in that, The condensing agent is 4-dimethylaminopyridine and N,N'-diisopropylcarbodiimide; in steps 3) and 4), solvent A is anhydrous N,N-dimethylformamide.

10. The method for preparing a perovskite solar cell based on the biomimetic mineralization principle according to claim 6, characterized in that, The specific method for step 2) is as follows: The perovskite precursor solution is dropped onto the biomolecular template layer, and then reacted in a closed environment with a relative humidity of 55-65% to begin crystallization. After crystallization is completed, the perovskite layer is obtained.

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