Perovskite solar cell based on pyridine sulfide derivative passivation and preparation method thereof

Abstract

The present application relates to the technical field of battery, especially to a perovskite solar cell based on passivation of pyridine sulfide derivative and a preparation method thereof. The perovskite solar cell comprises a perovskite thin film layer, a fullerene electron transport layer and a passivation layer, the fullerene electron transport layer and the passivation layer are sequentially covered on the surface of the perovskite thin film layer; the composition of the passivation layer is selected from pyridine sulfide derivative, the derivative is a triether compound, the halogen elements at both ends of the derivative fill in anion defects, and the tri-sulfide skeleton structure of the derivative can also coordinate with Pb ions to achieve passivation of divalent ions, so that the effect of double passivation is achieved. The test results of the core efficiency indicators and photovoltaic characteristic parameters of the perovskite solar cell based on pyridine sulfide derivative show that the pyridine sulfide derivative passivation layer can effectively improve the performance indicators of the perovskite solar cell in various aspects.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to perovskite solar cells based on pyridine sulfide derivative passivation and their preparation method. Background Technology

[0002] Perovskite solar cells (PSCs) have become a hot research topic in the photovoltaic field due to their high photoelectric conversion efficiency and low cost. However, their performance is limited by a large number of defects on the surface and grain boundaries of perovskite materials, which lead to nonradiative recombination and ion migration, seriously affecting the efficiency and stability of the devices.

[0003] Current research primarily focuses on reducing defects through passivation techniques, such as using 2D perovskites and organic molecular passivation layers to suppress grain boundary defects. However, traditional passivating agents are prone to dissociation under photothermal stress, leading to perovskite decomposition and phase separation. To improve stability, researchers have developed multifunctional passivating agents that achieve both thermodynamic and kinetic stability through strong coordination and dipole moment modulation. Furthermore, vapor-phase fluorination technology can achieve uniform passivation on large-area perovskite surfaces, suppressing defect formation and ion diffusion, thereby improving component efficiency and extending their lifespan. In lead-free exploration, biomolecules and silicon-based materials passivate tin-based perovskite surface defects through intermolecular interactions and interfacial layers, respectively, improving battery efficiency.

[0004] Therefore, developing passivation technology that combines high efficiency and high stability is an important aspect of promoting the practical application of perovskite solar energy. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the related art. To this end, the first objective of the present invention is to provide a perovskite solar cell based on pyridine sulfide derivative passivation; the second objective of the present invention is to provide a method for preparing a perovskite solar cell based on pyridine sulfide derivative passivation.

[0006] To achieve the first objective, the technical solution adopted by this invention is as follows:

[0007] A perovskite solar cell based on pyridine sulfide derivative passivation includes a perovskite thin film layer, a fullerene electron transport layer, and a passivation layer, wherein the fullerene electron transport layer and the passivation layer are sequentially covered on the surface of the perovskite thin film layer.

[0008] The passivation layer is composed of pyridine sulfide derivatives, and its structural formula is shown below:

[0009] R is selected from Cl, Br, or I;

[0010] The perovskite thin film contains Pb ions, which can coordinate with the three sulfur atoms in the pyridine sulfide derivative to form the following structure:

[0011] .

[0012] Perovskite films containing Pb ions exhibit anionic defects, leaving room for improvement in photocatalytic efficiency. Existing passivation layers are typically composed of halides or metal salts, which only address the anionic defect filling function. The passivation layer of this invention is composed of pyridine sulfide derivatives, which are triether compounds. While the halogens at both ends fill the anionic defect, the trisulfide framework can also coordinate with Pb ions to passivate divalent ions, thus achieving a dual passivation effect.

[0013] Fullerenes have a hollow cage-like structure, and the C in fullerenes 60 and C 70 They all exhibit significant interface passivation effects. In perovskite solar cells, they effectively suppress interface defects and improve device performance and stability through physical covering, chemical bonding, and energy level modulation.

[0014] Preferably, the perovskite solar cell comprises, from bottom to top, a substrate, a hole transport layer, a perovskite thin film layer, an electron transport layer, a passivation layer, and a metal electrode layer.

[0015] Preferably, the thickness of the passivation layer is 1–9 nm.

[0016] Preferably, the composition of the fullerene electron transport layer is selected from fullerene C. 60 or fullerene C 70 .

[0017] Preferably, the thickness of the fullerene transport layer is 10–200 nm.

[0018] Preferably, the substrate is selected from glass substrates containing indium tin oxide.

[0019] Preferably, the synthetic route for the pyridine sulfide derivative is as follows:

[0020] .

[0021] To achieve the second objective, the technical solution adopted by this invention is as follows:

[0022] A method for fabricating perovskite solar cells passivated with pyridine sulfide derivatives, for fabricating any of the perovskite solar cells passivated with pyridine sulfide derivatives as described above, includes the following steps:

[0023] S100. Prepare a perovskite precursor solution containing Pb, and spin-coat the perovskite precursor solution onto the surface of the substrate using spin-coating technology to obtain a perovskite thin film layer.

[0024] S200. Using vapor deposition technology, fullerene is vapor-deposited on the surface of the perovskite thin film layer to obtain a fullerene electron transport layer.

[0025] S300. Using vapor deposition technology, a pyridine sulfide derivative is vapor deposited on the surface of the fullerene electron transport layer to obtain a passivation layer.

[0026] Preferably, in step S100, a hole transport layer is covered on the surface of the substrate.

[0027] Preferably, the hole transport layer is composed of [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid.

[0028] Preferably, in step S100, the composition of the perovskite thin film layer is FA. 0.9 MA 0.05 Cs 0.05 Pb(I 0.95 Br 0.05 3;

[0029] In this context, FA represents formamidin, and MA represents methylamine.

[0030] The above-described one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0031] This invention provides a perovskite solar cell based on pyridine sulfide derivative passivation and its preparation method. The perovskite solar cell comprises a perovskite thin film layer, a fullerene electron transport layer, and a passivation layer, with the fullerene electron transport layer and the passivation layer sequentially covering the surface of the perovskite thin film layer. The passivation layer is composed of pyridine sulfide derivatives, which are triether compounds. The halogen elements at both ends of this derivative fill anion defects, while its trisulfide framework structure can coordinate with Pb ions to achieve passivation of divalent ions, thus achieving a dual passivation effect. Test results of the core efficiency and photovoltaic characteristic parameters of the perovskite solar cell based on the pyridine sulfide derivative show that the pyridine sulfide derivative passivation layer can effectively improve various performance indicators of the perovskite solar cell. Furthermore, the preparation method provided by this invention features mild reaction conditions, simple operation, and is conducive to large-scale production.

[0032] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0033] Figure 1 The proton nuclear magnetic resonance spectrum (PMR) of di[3-(6-bromopyridine)methyl]trisulfide provided in Example 1 of this invention is shown. 1 1H NMR spectrum.

[0034] Figure 2 The carbon-13 nuclear magnetic resonance (NMR) of di[3-(6-bromopyridine)methyl]trisulfide provided in Example 1 of this invention is shown. 13 C NMR spectrum.

[0035] Figure 3 This is a high-resolution mass spectrometry (HRMS) spectrum of di[3-(6-bromopyridine)methyl]trisulfide provided in Example 1 of the present invention.

[0036] Figure 4 This is a schematic diagram of the structure of a perovskite solar cell based on pyridine sulfide derivative passivation provided in Embodiment 2 of the present invention.

[0037] Figure label:

[0038] 1. Glass substrate; 2. Hole transport layer; 3. Perovskite thin film layer; 4. Electron transport layer; 5. Passivation layer; 6. Metal electrode layer. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. The following embodiments are used to illustrate this invention, but cannot be used to limit the scope of this invention.

[0040] In the following embodiments, unless otherwise specified, the experimental methods used are conventional methods, and the materials and reagents used are commercially available, unless otherwise specified, and are carried out in accordance with the techniques or conditions described in the literature in this field or in accordance with the product instructions.

[0041] Example 1

[0042] The structure of compound bis[3-(6-bromopyridine)methyl]trisulfide is shown below:

[0043] ;

[0044] The synthetic route is shown below:

[0045] ;

[0046] Its synthesis process is as follows:

[0047] 2.76 g of sodium thiosulfate pentahydrate (Na2S2O3·5H2O) was placed in a 250 mL four-necked flask, and then water (60 mL) was added. The solid compound was completely dissolved by magnetic stirring to obtain a reaction system containing an aqueous solution of sodium thiosulfate.

[0048] 2-Bromo-5-(bromomethyl)pyridine was heated in an oil bath at 55°C. (2.77 g) was dissolved in ethanol (20 mL) to obtain a 2-bromo-5-(bromomethyl)pyridine ethanol solution, which was added dropwise to a reaction system containing sodium thiosulfate aqueous solution. The reaction was kept at 55 °C and stirred for 2 h. TLC monitoring was performed until the starting material spot disappeared (the developing solvent was a mixed solvent of petroleum ether and ethyl acetate, with a volume ratio of petroleum ether to ethyl acetate of 15:1). Heating and stirring were stopped, and the reaction system was cooled to 0-3 °C.

[0049] 1.36 g of sodium sulfide nonahydrate (Na2S·9H2O) was dissolved in water (10 mL) to obtain an aqueous solution of sodium sulfide. This aqueous solution was slowly added dropwise to the above reaction system, producing a large amount of yellow precipitate. After stirring at 0-3℃ for 2 h, the mixture was filtered to obtain a filter cake. The filter cake was added to dichloromethane (50 mL) and water (50 mL) and stirred to dissolve. After standing and separating the liquid, the aqueous phase was discarded. The organic phase was washed with saturated brine and collected. The organic phase was dried with anhydrous sodium sulfate for 12 h and then filtered. The filtrate was concentrated under reduced pressure to remove the solvent, yielding di[3-(6-bromopyridine)methyl]trisulfide (1.57 g).

[0050] The melting point (mp) of di[3-(6-bromopyridine)methyl]trisulfide is 133–134 °C;

[0051] That 1 H NMR, 13 C NMR and HRMS are respectively as follows Figure 1 , Figure 2 and Figure 3 As shown;

[0052] in, 1 H NMR (400MHz, CDCl3, ppm) δ 8.28 (s, 2H, Ar-H), 7.60–7.36 (m, 4H, Ar-H), 3.94 (s, 4H, Ar-CH2-);

[0053] 13 C NMR (101MHz, CDCl3, ppm) δ 150.75, 141.45, 139.50, 131.81, 128.20, 38.92;

[0054] HRMS(ESI) m / z [M+Na] + C 12 H 10 Br2N2NaS3: Calculated value is 458.8271, actual value is 458.8268.

[0055] Example 2

[0056] Perovskite solar cells passivated with pyridine sulfide derivatives include, from bottom to top, a glass substrate 1, a hole transport layer 2, a perovskite thin film layer 3, an electron transport layer 4, a passivation layer 5, and a metal electrode layer 6, as follows: Figure 4 As shown, its preparation process is as follows:

[0057] I. Preparation of the glass substrate: The process is as follows: Electrode patterns are etched on indium tin oxide (ITO) conductive glass (sheet resistance 15Ω, thickness 200nm, transmittance >85%) using laser etching (laser wavelength 355nm, power 10W, etching depth 50nm). After cleaning the surface with purified water to remove dust, the conductive glass is placed in glass cleaning agent, purified water, acetone, ethanol, and isopropanol in sequence, and ultrasonically cleaned for 20 minutes each (ultrasonic power 300W). After cleaning, the conductive glass is placed in a UV cleaner (UV wavelength 254nm, power 150W) for 15 minutes to obtain a clean glass substrate.

[0058] II. Preparation of the hole transport layer, the process is as follows:

[0059] 1.1 mg of [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz) was added to ethanol (2 mL) and stirred at room temperature until dissolved to obtain a precursor solution of hole transport layer with a concentration of 0.55 mg / mL.

[0060] The glass substrate is placed on a spin coater and, under dry air (humidity <30% RH) conditions, the spin coater is operated at 3500 rpm for 25 seconds (during the first 3 seconds, the precursor solution is dropped and spin-coated onto the center of the glass substrate) to spin-coat the precursor solution of the aforementioned hole transport layer onto the surface of the glass substrate. Then, the glass substrate is immediately placed on a heating plate and annealed at 105°C for 15 minutes to obtain a hole transport layer that covers the surface of the glass substrate.

[0061] III. Preparation of the perovskite thin film layer, the process is as follows:

[0062] CsI ​​(66.5 mg), formamidin hydroiodide (FAI) (836.0 mg), and PbI2 (2359.7 mg) were added to a mixed solvent (3 ml, DMF to DMSO volume ratio 5:1) consisting of dimethyl formamide (DMF) and dimethyl sulfoxide (DMSO). After dissolution, solution I was obtained.

[0063] Methylammonium bromide (MABr) (190 mg) and PbBr2 (622.7 mg) were added to a mixed solvent of DMF and DMSO (1 ml, DMF to DMSO volume ratio of 3:1) to obtain solution II;

[0064] Take solution I (2.85 mL) and solution II (0.15 mL) and mix them evenly. Then add methylammonium chloride (MACl) (32.0 mg) and dissolve to obtain perovskite precursor solution.

[0065] Under nitrogen atmosphere, a glass substrate covered with a hole transport layer was placed on a spin coater, and 0.75 mL of perovskite precursor solution was added to the surface of the hole transport layer. The spin coater was maintained at 1200 rpm for 15 s, and then at 5500 rpm for 35 s. At the 30th second of the 35 s spin coater, 1.5 mL of anisole antisolvent was added to precipitate perovskite crystals. Immediately after the perovskite crystals precipitated, the glass substrate covered with the hole transport layer was placed on a hot plate and annealed at 110 °C for 15 min to obtain a perovskite thin film layer covering the surface of the hole transport layer.

[0066] The molecular formula of the perovskite component is FA. 0.9 MA 0.05 Cs 0.05 Pb(I 0.95 Br 0.05 3.

[0067] IV. Fabrication of the electron transport layer, the process is as follows:

[0068] Using a vacuum evaporation apparatus (vacuum level: substrate chamber 10) -4 Pa, evaporation chamber 10 -5 Pa; Evaporation source temperature: 400℃; Evaporation rate: 0.3 Å / s), a 200 nm thick C film was deposited on the surface of the perovskite thin film. 60 Immediately afterwards, it was annealed at 60°C for 15 minutes in a nitrogen atmosphere to obtain a product with the composition C. 60 An electron transport layer is formed on the surface of the perovskite thin film layer.

[0069] V. Preparation of the passivation layer, the process is as follows:

[0070] Using a vacuum evaporation apparatus (vacuum level: substrate chamber 10) -4 Pa, evaporation chamber 10 -5 Pa; Evaporation source temperature: 180℃; Evaporation rate: 0.2Å / s), a 5nm thick layer of di[3-(6-bromopyridine)methyl]trisulfide is deposited on the surface of the aforementioned electron transport layer as a passivation layer, which covers the surface of the electron transport layer.

[0071] VI. Preparation of the metal electrode layer, the process is as follows:

[0072] A 100 nm thick Cu layer was deposited on the aforementioned passivation layer using electron beam evaporation technology (with the deposition rate controlled at around 0.3 nm / s) as a metal electrode layer. This metal electrode layer covered the surface of the passivation layer, resulting in a perovskite solar cell based on pyridine sulfide derivative passivation.

[0073] Perovskite solar cell samples based on pyridine sulfide derivative passivation with passivation layer thicknesses of 1 nm, 3 nm, 5 nm, 7 nm and 9 nm, prepared according to the above process, were subjected to subsequent performance testing.

[0074] Comparative Example 1

[0075] The perovskite solar cell without a passivation layer has the same structural composition as in Example 2, except that it does not include the passivation layer. The preparation process for the cell without the passivation layer is the same as in Example 2.

[0076] The photoelectric conversion efficiency of the perovskite solar cell based on pyridine sulfide derivative obtained in Example 2 and the perovskite solar cell without passivation layer obtained in Comparative Example 1 were tested respectively. The test results are shown in the table below:

[0077]

[0078] In the table, PCE stands for Power Conversion Efficiency.

[0079] As shown in the table above, the perovskite solar cell based on pyridine sulfide derivatives provided by this invention exhibits overall improved performance parameters compared to Comparative Example 1, validating the positive effect of the passivation layer. Specifically, when the passivation layer thickness is 5 nm, all photoelectric performance parameters (PCE, open-circuit voltage, short-circuit current, and fill factor) reach their optimal values.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A perovskite solar cell based on passivation by pyridine sulfide derivatives, characterized in that, The perovskite thin film layer, a fullerene electron transport layer and a passivation layer, the fullerene electron transport layer and the passivation layer are sequentially covered on the surface of the perovskite thin film layer. The passivation layer is composed of a pyridine sulfide derivative, and the structural formula is as follows: R is selected from any one of CI, Br or I; The perovskite thin film layer contains Pb ions, and the Pb ions can be coordinated with three sulfur atoms in the pyridine sulfide derivative to form the following structure: 。 2. The perovskite solar cell passivated based on pyridine sulfide derivative according to claim 1, characterized in that, The perovskite solar cell sequentially comprises a substrate, a hole transport layer, a perovskite thin film layer, an electron transport layer, a passivation layer and a metal electrode layer from bottom to top. 3.The perovskite solar cell passivated based on pyridine sulfide derivative according to claim 1, characterized in that, The thickness of the passivation layer is 1-9 nm.

4. The perovskite solar cell passivated based on pyridine sulfide derivative according to claim 1, characterized in that, The composition of the fullerene electron transport layer is selected from fullerene C 60 or fullerene C 70 with a thickness of 10-200 nm. 5.The perovskite solar cell based on passivation by pyridine sulfide derivative according to claim 2, wherein The substrate is selected from an indium tin oxide-containing glass substrate. 6.The perovskite solar cell based on passivation by pyridine sulfide derivative according to claim 1, wherein The synthesis route of the pyridine sulfide derivative is as follows: 。 7. A method for preparing a perovskite solar cell based on passivation by pyridyl sulfide derivatives, characterized by, A method for preparing the perovskite solar cell based on pyridine sulfide derivative passivation according to any one of claims 1-6, comprising the following steps: S100, preparing a Pb-containing perovskite precursor solution, and using a spin coating technique to spin coat the perovskite precursor solution on the surface of the substrate to obtain a perovskite thin film layer; S200, using an evaporation technique to evaporate fullerene on the surface of the perovskite thin film layer to obtain a fullerene electron transport layer; S300, using an evaporation technique to evaporate a pyridine sulfide derivative on the surface of the fullerene electron transport layer to obtain a passivation layer. 8.The method of manufacturing a perovskite solar cell based on passivation by pyridine sulfide derivative according to claim 7, wherein, In step S100, the surface of the substrate is covered with a hole transport layer. 9.The method of claim 8, wherein the pyridine sulfide derivative is represented by the following formula 1: The composition of the hole transport layer is selected from [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl] phosphonic acid. ​ 10.The method of manufacturing a perovskite solar cell based on passivation by pyridine sulfide derivative according to claim 7, wherein, In step S100, the perovskite thin film layer has a composition of FA 0.9 MA 0.05 Cs 0.05 Pb(I 0.95 Br 0.05 )3; Wherein, FA represents formamidine, and MA represents methylamine.

Images