Perovskite solar cell module and preparation method thereof

Abstract

The invention is suitable for the technical field of solar cells, and provides a perovskite solar cell module and a preparation method thereof. The perovskite solar cell module comprises an anode, a hole transport layer, a perovskite layer, an electron transport layer and a cathode which are sequentially laminated. An optical active material used for preparing the perovskite layer is metal halide perovskite, and the specific chemical formula is Cs0. 15FA0. 85PbI3; and a cathode interface material used for preparing the cathode interface layer is quinacridone derivative (DCNQA-PyBr). According to the invention, DCNQA-PyBr is used as the cathode interface material to be applied to the perovskite (such as a Cs0. 15FA0. 85PbI3 system) solar cell module, the thick film processing of the cathode interface material can be realized, the energy conversion efficiency of the perovskite solar cell module is improved, and the cathode interface material is suitable for large-scale production and can meet the requirement of large-area industrial production.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar cells, and in particular relates to a perovskite solar cell assembly and a preparation method thereof. Background Art

[0002] Perovskite solar cells (PVSCs) are considered an effective solution to environmental pollution and the energy crisis. Due to their unique material advantages, such as low exciton binding energy, long carrier diffusion length, high absorption coefficient, tunable band gap, and high carrier mobility, they are considered a new generation of green energy technology with significant industrial prospects. Over the past decade, thanks to the continuous development of perovskite composition optimization, additive engineering, passivation engineering, and interface engineering, the power conversion efficiency (PCE) of solution-processed PVSCs has been significantly improved from 3.8% to 26.8%. Commonly used pin-inverted PVSCs consist of a photoactive perovskite layer, electrodes (including cathode and anode), interface (including cathode and anode) modification layers, and transport layers (including electrons and holes). The introduction of a cathode interface layer (CIL) between the photoactive perovskite layer and the cathode can reduce the electron extraction barrier, promote the formation of ohmic contact between the active layer and the cathode, and improve device performance.

[0003] As organic solar cells (OSCs) continue to commercialize, the demand for energy conversion efficiency is increasing. Consequently, developing cathode interface materials with high conductivity and the ability to support thick film processing has become a major challenge for researchers. To address this issue, the present invention proposes a perovskite solar cell module and a method for its preparation. Summary of the Invention

[0004] The object of the present invention is to provide a perovskite solar cell module and a preparation method thereof, aiming to solve the problems raised in the above background technology.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A method for preparing a perovskite solar cell module comprises the following steps:

[0007] P1 scribing: Laser scribing is performed on the anode surface to vaporize the anode material and form a groove line P1;

[0008] Preparation of hole transport layer: Two hole transport material solutions are coated on the laser-scribed anode surface and annealed separately to form a hole transport layer on the anode surface;

[0009] Preparation of the perovskite layer: A precursor of a photoactive material solution is applied to the surface of the hole transport layer, and the solution is continuously spin-coated in two steps, low speed and high speed. During the high-speed spin coating, an anti-solvent is added to the substrate. After annealing, a perovskite film is obtained, and a perovskite layer is formed on the surface of the hole transport layer.

[0010] The photoactive material used to prepare the perovskite layer is a metal halide perovskite, which is a cubic crystal material with a molecular formula of ABX3, wherein A is Cs + and FA + ; B is Pb 2+ , X is I - The specific chemical formula of the perovskite layer material is Cs 0.15 FA 0.85 PbI3;

[0011] Preparation of electron transport layer: coating the surface of the perovskite layer with an electron transport material solution, and then removing the solvent to form an electron transport layer on the surface of the perovskite layer;

[0012] Preparation of cathode interface layer: coating cathode interface material solution on the surface of electron transport layer, and forming cathode interface layer on the surface of electron transport layer after removing solvent;

[0013] P2 scribing: Laser scribing is performed on the surface of the electron transport layer to vaporize the hole transport layer, perovskite layer, electron transport layer, and cathode interface layer materials and form groove lines P2;

[0014] Cathode preparation: preparing a cathode on the surface of the cathode interface layer;

[0015] P3 scribing: Laser scribing is performed on the cathode surface to vaporize the hole transport layer, perovskite layer, electron transport layer, cathode interface layer, and cathode material to form groove lines P3; the entire film layer is divided into sub-cells connected in series to form separate modules that block current conduction, thereby increasing the voltage and connecting the cells in series to obtain a perovskite solar cell module;

[0016] P4 edge cleaning: Laser P4 edge cleaning is performed to remove all film layers at the edge of the substrate to form an insulating area, which will serve as the packaging area for subsequent perovskite solar cell modules.

[0017] Furthermore, the material of the anode is indium tin oxide (ITO), and the material of the cathode is metal.

[0018] Furthermore, the hole transport material used to prepare the hole transport layer is nickel oxide (NiO X ) and [2-(9H-carbazol-9-yl)ethyl]phosphoric acid (2PACz).

[0019] Furthermore, the photoactive material is a cubic crystal CsI formed by crystallizing a mixture of CsI, MACl, FAI, PbI2 and PbCl2. 0.15 FA 0.85 The chemical molar ratio of PbI3, CsI, MACl, FAI, PbI2 and PbCl2 is 0.15:0.025:0.85:0.975:0.025.

[0020] Furthermore, when the cathode interface material used to prepare the cathode interface layer is a quinacridone derivative, the cathode interface material solution is a quinacridone derivative solution; and the concentration of the quinacridone derivative solution is 7.5 mg / mL.

[0021] A perovskite solar cell assembly prepared according to the above-mentioned preparation method comprises an anode, a hole transport layer, a perovskite layer, an electron transport layer, a cathode interface layer and a cathode stacked in sequence.

[0022] Furthermore, the cathode interface material used to prepare the cathode interface layer is a quinacridone derivative, and the quinacridone derivative has a structure shown in Formula I:

[0023]

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention uses DCNQA-PyBr as cathode interface material for perovskite (such as Cs 0.15 FA 0.85 In PbI3 system) solar cell modules, it can realize thick film processing of cathode interface materials, improve the energy conversion efficiency of perovskite solar cell modules, is suitable for large-scale production, and can meet the needs of large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the perovskite solar cell module in the present invention.

[0027] Figure 2 For Example 1 with Cs 0.15 FA 0.85 Current-voltage curves of a perovskite solar cell module with a PbI3 perovskite active layer and a 30 nm thick DCNQA-PyBr cathode interface layer.

[0028] Figure 3 This is a physical photo of the perovskite solar cell module prepared in Example 1. DETAILED DESCRIPTION

[0029] In order to have a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be understood as limiting the scope of implementation of the present invention.

[0030] The present invention provides a perovskite solar cell component, such as Figure 1 As shown, it includes an anode (ITO layer), a hole transport layer, a perovskite layer, an electron transport layer, a cathode interface layer and a cathode (metal electrode layer) stacked in sequence;

[0031] In an embodiment of the present invention, the material of the anode is preferably indium tin oxide (ITO); the thickness of the anode is preferably 120-150 nm, more preferably 130-140 nm, and further preferably 135 nm.

[0032] The hole transport layer is in contact with one side surface of the anode. The hole transport material used to prepare the hole transport layer preferably includes nickel oxide (NiO X )(CAS No.1313-99-1) and [2-(9H-carbazol-9-yl)ethyl]phosphoric acid (2PACz) (CAS No.20999-38-6), respectively produced by Liaoning Youxuan New Energy Technology Co., Ltd., China. X It was prepared by using deionized water solution and 2PACz ethanol solution produced by Xi'an Yuri Solar Energy Technology Co., Ltd., China. X and 2PACz as hole transport materials, denoted as NiO X / 2PACz hole transport layer. NiO X The thickness of the hole transport layer is preferably 10 to 50 nm, more preferably 20 to 40 nm, and further preferably 35 nm; the thickness of the 2PACz hole transport layer is preferably 2 to 10 nm, more preferably 4 to 8 nm, and further preferably 7 nm.

[0033] The perovskite layer is in contact with the hole transport side surface. The photoactive material used to prepare the perovskite layer is a cubic crystal material CsI, MACl, FAI, PbI2 and PbCl2 mixed solution crystallized. 0.15 FA 0.85PbI3 includes inorganic halide materials and organic halide materials. The inorganic halide includes CsI (CAS No. 7789-17-5), PbI2 (CAS No. 10101-63-0), and PbCl2 (CAS No. 7758-95-4). The organic halide materials include MACl (CAS No. 593-51-1) and FAI (CAS No. 879643-71-7). The stoichiometric ratio of CsI, MACl, FAI, PbI2, and PbCl2 is preferably 0.2:0.025:0.8:0.98:0.02, more preferably 0.15:0.025:0.85:0.975:0.025. The thickness of the perovskite layer is preferably 500 to 800 nm, more preferably 600 to 700 nm, and even more preferably 650 nm. The structural formulas of CsI, MACl, FAI, PbI2 and PbCl2 are shown below:

[0034]

[0035] The electron transport layer is in contact with one side surface of the perovskite layer. The electron transport material used to prepare the electron transport layer is PC 61 BM (CAS No. 160848-22-6), the thickness of the electron transport layer is preferably 30 to 60 nm, more preferably 40 to 50 nm, and further preferably 45 nm. PC 61 The structural formula of BM is as follows:

[0036]

[0037] The cathode interface layer is in contact with one side surface of the electron transport layer. The cathode interface material used to prepare the cathode interface layer is a quinacridone derivative (abbreviated as DCNQA-PyBr). DCNQA-PyBr is an ionic compound containing quinacridone. Based on the excellent solubility of DCNQA-PyBr in alcohol solutions, it is convenient to form a film by solution coating, doctor blade coating or slit coating, which can realize thick film processing of the cathode interface layer. DCNQA-PyBr is used as a cathode interface layer in perovskite solar cell modules to obtain higher energy conversion efficiency. During the scraper coating process, first adjust the operating program of the scraper, move the scraper to the scraping starting position, set the height to 60μm, the moving speed to 20mm / s, set the coating table to 50°C, and preheat for 10min. Then place the sample to be scraped on the coating table, and start the adsorption program of the scraper table. Then, 10 μL of DCNQA-PyBr in trifluoroethanol was evenly spread in the gap between the blade and the sample, and the program was started to evenly coat it on the substrate, thereby forming a cathode interface layer. The quinacridone derivative has the structure shown in Formula I:

[0038]

[0039] The cathode is in contact with one surface of the cathode interface layer. The cathode is preferably made of metal, more preferably copper. The thickness of the cathode is preferably 80 to 120 nm, more preferably 90 to 110 nm, and even more preferably 100 nm.

[0040] The present invention provides a method for preparing the above-mentioned perovskite solar cell module, comprising the following steps:

[0041] P1 scribing (first laser etching): laser scribing is performed on the anode surface to vaporize the anode material and form a groove line P1;

[0042] Preparation of hole transport layer: Two hole transport material solutions are coated on the laser-scribed anode surface and annealed separately to form a hole transport layer on the anode surface;

[0043] Preparation of the perovskite layer: A precursor of a photoactive material solution is applied to the surface of the hole transport layer, and the solution is continuously spin-coated in two steps, low speed and high speed. During the high-speed spin coating, an anti-solvent is added to the substrate. After annealing, a perovskite film is obtained, and a perovskite layer is formed on the surface of the hole transport layer.

[0044] Preparation of electron transport layer: coating the surface of the perovskite layer with an electron transport material solution, and then removing the solvent to form an electron transport layer on the surface of the perovskite layer;

[0045] Preparation of cathode interface layer: coating cathode interface material solution on the surface of electron transport layer, and forming cathode interface layer on the surface of electron transport layer after removing solvent;

[0046] P2 scribing (second laser etching): laser scribing is performed on the surface of the electron transport layer to vaporize the hole transport layer, perovskite layer, electron transport layer and cathode interface layer materials and form groove lines P2;

[0047] Cathode preparation: preparing a cathode on the surface of the cathode interface layer;

[0048] P3 scribing: Laser scribing is performed on the cathode surface to vaporize the hole transport layer, perovskite layer, electron transport layer, cathode interface layer, and cathode material to form a third dividing line, namely, groove line P3. Through the P1, P2, and P3 scribing lines, the entire film layer is divided into sub-cells connected in series, forming separate modules that block current conduction, thereby achieving the effect of increasing voltage and connecting cells in series, thus obtaining a perovskite solar cell module.

[0049] P4 edge cleaning: Laser P4 edge cleaning is performed to remove all film layers at the edge of the substrate to form an insulating area, which will serve as the packaging area for subsequent perovskite solar cell modules.

[0050] In the examples of the present invention, unless otherwise specified, the raw materials or reagents used are commercially available products well known to those skilled in the art or are prepared using methods well known to those skilled in the art.

[0051] When the material of the anode is ITO, it is preferred to obtain the anode by magnetron sputtering coating on the substrate, and then further prepare a hole transport layer on the anode. The substrate is preferably a sodium-calcium-based glass sheet. The present invention has no special requirements for the specific conditions adopted when magnetron sputtering coats the anode. By adopting the coating conditions well known to those skilled in the art, an anode having a thickness and transmittance that meet the requirements can be obtained. The first laser etching is performed on the anode to vaporize the anode material and form a first dividing line, i.e., the groove line P1, on the anode. The present invention has no special requirements for the specific conditions adopted when laser scribing. By adopting the laser scribing conditions well known to those skilled in the art, it is sufficient to scribe the ITO layer through without craters.

[0052] The solvents in the two material solutions of the hole transport layer are preferably deionized water and anhydrous ethanol; when the hole transport material is nickel oxide (NiO X ), the hole transport material solution is preferably NiO X deionized water solution; preferably NiO X The deionized water solution was filtered through a 0.45 μm aqueous polyethersulfone (PES) filter membrane before use. X The concentration is preferably 20 to 40 mg / mL, more preferably 30 mg / mL. XThe hole transport material solution is preferably coated by dynamic spin coating, with a spin coating speed of preferably 2000-4000 r / min, more preferably 3000 r / min; and a spin coating time of preferably 20-60 s, more preferably 30 s. X The hole transport layer is preferably annealed to remove the solvent; the annealing temperature is preferably 100-200°C, more preferably 150°C; the annealing time is preferably 10-20 minutes, more preferably 15 minutes. Annealing can remove the solvent in the wet film, thereby improving the stability of the perovskite solar cell. X After the hole transport layer, the NiO X The hole transport layer is coated with [2-(9H-carbazol-9-yl)ethyl]phosphoric acid (2PACz) hole transport material solution, and NiO is formed on the anode surface after removing the solvent. X / 2PACz hole transport layer. When the hole transport material is [2-(9H-carbazol-9-yl)ethyl]phosphoric acid (2PACz), the hole transport material solution is preferably an anhydrous ethanol solution of 2PACz; the anhydrous ethanol solution of 2PACz is preferably filtered through a 0.45μm polytetrafluoroethylene (PTFE) filter membrane before use. The concentration of 2PACz is preferably 0.3-1mg / mL, more preferably 0.5mg / mL. The coating method of the 2PACz hole transport material solution is preferably spin coating, and the spin coating speed is preferably 2000-4000r / min, more preferably 3000r / min; the spin coating time is preferably 30-60s, more preferably 40s. The method of removing the solvent from the 2PACz hole transport layer is preferably annealing treatment; the annealing temperature is preferably 80-150℃, more preferably 100℃; the annealing time is preferably 5-20min, more preferably 10min. Annealing treatment can remove the solvent in the wet film, which is beneficial to improving the stability of perovskite solar cell modules.

[0053] The photoactive materials used to prepare the perovskite layer were purchased from Liaoning Youxuan New Energy Technology Co., Ltd. in China. The concentration of the photoactive material solution in the photoactive material solution is preferably 1 to 2 M, more preferably 1.6 M. The solvent in the photoactive material solution is a mixed solvent of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), and the volume ratio of DMF / DMSO is preferably 3 to 5:1, more preferably 4:1, which can ensure that the photoactive material is fully dissolved. The photoactive material solution of the present invention does not require the use of additives. The coating method of the photoactive material solution is preferably spin coating, and the solution containing the photoactive material is coated on the substrate and spin-coated in two consecutive steps. The first step spin coating speed is preferably 800 to 1200 r / min, more preferably 1000 r / min, and the spin coating time is preferably 5 to 15 s, more preferably 10 s. The second step spin coating speed is preferably 4000 to 6000 r / min, more preferably 5000 r / min, and the spin coating time is preferably 20 to 40 s, more preferably 30 s. The anti-solvent chlorobenzene (CB) is rapidly dripped onto the substrate 5 to 10 seconds before the end of the second high-speed spin coating step, preferably 8 seconds. The temperature for the annealing treatment of the perovskite layer thin film is preferably 80 to 120°C, more preferably 100°C, and the annealing time is preferably 10 to 40 minutes, more preferably 30 minutes. The annealing treatment can remove the solvent in the wet film, thereby forming a perovskite layer on the surface of the hole transport layer; and the annealing treatment can change the morphology and crystallinity of the perovskite layer, forming a channel that is conducive to charge transport and obtaining a cubic crystallized perovskite layer thin film, thereby improving the energy conversion efficiency of the perovskite solar cell module.

[0054] The above-mentioned method for preparing the perovskite layer is to add anti-solvent by solution spin coating and thermally anneal to form crystals. The same formula can be used for solution spin coating, quickly transferred to a vacuum negative pressure box, and thermally annealed to form crystals after rapid vacuuming (in order to remove excess precursor solution, the prepared wet film is transferred to a vacuum negative pressure box that can reach 200Pa within 2s. By controlling the vacuum treatment time to accelerate the evaporation of the solvent, the wet film quickly reaches an oversaturated state, and the perovskite nucleation process is promoted. When the color of the wet film gradually changes from transparent to dark yellow, it is transferred to a heating plate under atmospheric conditions, and its annealing time at 100°C is adjusted to prepare a densely crystalline perovskite film).

[0055] The solvent of the electron transport material solution is preferably chlorobenzene. The electron transport material is PC 61 BM (purchased from Liaoning Youxuan New Energy Technology Co., Ltd., China), the electron transport material solution is preferably PC 61 BM solution, specifically PC 61 BM was dissolved in chlorobenzene; PC 61The concentration of the BM solution is preferably 10 to 45 mg / mL, preferably 20 mg / mL. The coating method of the electron transport material solution is preferably spin coating, and the spin coating speed is preferably 800 to 2000 r / min, more preferably 1200 r / min. The present invention has no special requirements for the spin coating time, as long as the solvent in the wet film obtained after spin coating is removed to obtain an electron transport layer with the required thickness.

[0056] The solvent of the cathode interface material solution is preferably methanol. When the cathode interface material is DCNQA-PyBr, the cathode interface material solution is preferably a DCNQA-PyBr solution, specifically obtained by dissolving DCNQA-PyBr in methanol; the concentration of the DCNQA-PyBr solution is preferably 2 to 12 mg / mL, more preferably 7.5 mg / mL. The coating method of the cathode interface material solution is preferably spin coating, and the spin coating speed is preferably 2000 to 3000 r / min, more preferably 2500 r / min; the present invention has no special requirements for the spin coating time, as long as the solvent in the wet film obtained after spin coating is removed to obtain a cathode interface layer with a thickness that meets the requirements. The present invention preferably removes the solvent in the wet film by negative pressure vacuum treatment.

[0057] When the cathode is made of metal, it is preferred to deposit the cathode on the surface of the cathode interface layer; the metal raw material used for the deposited cathode is a commercially available commodity well known to those skilled in the art. The present invention has no particular limitation on the form of the metal raw material, which may be metal powder, metal strip, metal sheet or metal block. The deposition speed is preferably More preferably More preferably The vacuum degree of evaporation is preferably (1.7 to 1.9) × 10 -4 Pa, more preferably 1.8×10 -4 Pa; the evaporation current is preferably 32 to 40 A, more preferably 34 to 37 A; the evaporation voltage is preferably 2 to 4 V, more preferably 3.5 to 4 V; the evaporation time is based on ensuring that the thickness of the cathode meets the requirements.

[0058] The perovskite solar cell module consists of 6 sub-cells connected in series, with a total active area of ​​12.44cm 2 .

[0059] The specific implementation of the present invention is described in detail below with reference to specific examples. The DCNQA-PyBr involved in the examples was prepared with reference to the literature (J. Mater. Chem. A, 2016, 4, 2169-2177), specifically comprising the following steps:

[0060] QA-PyBr (1.74 g, 2.50 mmol), malononitrile (0.33 g, 5.00 mmol) and 300 mL of dry CH2Cl2 were placed in a 500 mL three-necked flask, and TiCl4 (14.25 g, 75.0 mmol) was added dropwise to the three-necked flask in an ice-water bath at 0°C. After the addition was complete, the mixture was stirred for 10 minutes, and then dry pyridine (31.60 g, 400.0 mmol) was added dropwise. After the addition was complete, the temperature was naturally raised to room temperature (25°C) and the reaction was carried out for 24 hours. After the reaction was completed, all solvents in the obtained product system were dried, and the residue was separated by 200-300 mesh silica gel column chromatography using dichloromethane as eluent to obtain a dark green solid DCNQA-Br (1.34 g, 68%).

[0061] DCNQA-Br (1.98 g, 2.50 mmol) and 100 mL of pyridine were placed in a 250 mL three-necked flask and heated under reflux overnight. A precipitate gradually formed in the system. After cooling to room temperature, the mixture was filtered. The filter cake was washed with 100 mL of CH2Cl2 and dried to obtain a dark green solid, DCNQA-PyBr (2.15 g, 81%). Elemental analysis of the prepared product confirmed that the product was DCNQA-PyBr.

[0062] The structural formula of QA-PyBr is shown in Formula II:

[0063]

[0064] Example 1: Preparation of ITO / NiO X / 2PACz / Cs 0.15 FA 0.85 PbI3 / PC 61 BM / DCNQA-PyBr / Cu perovskite solar cell module, the steps are as follows:

[0065] An ITO with a thickness of 135 nm is obtained by magnetron sputtering on a glass substrate as an anode. A first laser etching is performed on the surface of the ITO anode to vaporize the ITO material and form a first separation line, ie, a groove line P1, on the anode.

[0066] NiO X Dispersed in deionized water solvent with a concentration of 30 mg / ml. Filtered with a 0.45 μm PES filter membrane, then dynamically spin-coated on the anode surface at a speed of 3000 r / min for 30 seconds, annealed at 150 ° C for 15 minutes, and formed a 35 nm thick NiO layer on the anode surface. X Hole transport layer, ITO / NiO XDevice; 2PACz was dissolved in anhydrous ethanol solvent at a concentration of 0.5 mg / ml. Filtered with a 0.45 μm PTFE filter membrane, and then spin-coated on NiO at a speed of 3000 r / min for 40 seconds. X The hole transport layer surface was annealed at 100℃ for 10min. X A 2PACz hole transport layer with a thickness of 7 nm was formed on the surface of the hole transport layer to obtain ITO / NiO X / 2PACz device, and then transferred to the glove box;

[0067] CsI, MACl, FAI, PbI2 and PbCl2 were mixed with a DMF / DMSO mixed solvent to obtain a perovskite precursor solution. The chemical molar ratio of CsI, MACl, FAI, PbI2 and PbCl2 in the perovskite precursor solution was 0.15:0.025:0.85:0.975:0.025; the volume ratio of solvent DMF to solvent DMSO was 4:1; the concentration of the perovskite precursor solution was 1.6M. The perovskite precursor solution was added dropwise to NiO X / 2PACz hole transport layer, by continuous two-step spin coating (slow speed step spin coating speed 1000r / min, time 10s and high speed step spin coating 5000r / min, time 30s), 8s before the end of the high speed spin coating step, the anti-solvent chlorobenzene was quickly added to the substrate, followed by annealing at 100℃ for 30min. X A perovskite layer with a thickness of 550 nm is formed on the surface of the ITO / NiO hole transport layer. X / 2PACz / Cs 0.15 FA 0.85 PbI3 devices;

[0068] PC 61 BM was dissolved in chlorobenzene to obtain PC at a concentration of 20 mg / ml. 61 The BM solution was filtered with a 0.45 μm hydrophobic PTFE filter membrane and then spin-coated on the surface of the perovskite layer at a speed of 1200 r / min to form a PC with a thickness of 45 nm on the surface of the perovskite layer. 61 BM electron transport layer, ITO / NiO X / 2PACz / Cs 0.15 FA 0.85 PbI3 / PC 61 BM devices;

[0069] A 7.5 mg / mL DCNQA-PyBr methanol solution was used as the cathode interface material solution. The cathode interface material solution was stirred at a speed of 2500 r / min on a Cs 0.15 FA0.85 The surface of the PbI3 perovskite active layer was spin-coated for 40 seconds, and then the solvent was removed by vacuum treatment under negative pressure to form a DCNQA-PyBr cathode interface layer with a thickness of 30 nm on the surface of the PBDB-T:ITIC active layer to obtain ITO / NiO X / 2PACz / Cs 0.15 FA 0.85 PbI3 / PC 61 BM / DCNQA-PyBr devices;

[0070] Perform a second laser etching on the surface of the electron transport layer, using laser scribing to vaporize the hole transport layer, perovskite layer, electron transport layer and cathode interface layer materials to form a second separation line, i.e., groove line P2;

[0071] ITO / NiO X / 2PACz / Cs 0.15 FA 0.85 PbI3 / PC 61 The BM / DCNQA-PyBr device is placed in the evaporation chamber. A Cu metal layer with a thickness of 100 nm was deposited on the surface of the DCNQA-PyBr cathode interface layer as the cathode (the vacuum degree during vacuum deposition was 1.8×10 -4 Pa, current is 35A, voltage is 3.6V);

[0072] The cathode surface is laser etched for the third time, and the hole transport layer, perovskite layer, electron transport layer, cathode interface layer and cathode material are vaporized by laser scribing to form the third dividing line, namely the groove line P3; the entire film layer is divided into sub-cells connected in series, thus forming a separate module that blocks current conduction, thereby achieving the effect of increasing voltage and connecting cells in series. Finally, ITO / NiO X / 2PACz / Cs 0.15 FA 0.85 PbI3 / PC 61 BM / DCNQA-PyBr / Cu perovskite solar cell module ( Figure 3 The perovskite solar cell module is composed of 6 sub-cells connected in series, with a total effective area of ​​12.44cm 2 .

[0073] The performance test of the perovskite solar cell module prepared in this embodiment was carried out, and the results are as follows: Figure 2 shown. Figure 2 The open circuit voltage of the perovskite solar cell module is 6.58 V and the short circuit current density is 3.93 mA / cm 2, the filling factor is 0.683, and the energy conversion efficiency of the perovskite solar cell assembly is calculated to be 17.67%.

[0074] (1) Short-circuit current density (J SC );

[0075] Under light conditions, the current density when the device is in a short circuit (voltage is 0) is the short-circuit current density, unit is mA / cm 2 ). J SC It is mainly related to the absorption of light by the perovskite layer. The larger the absorption spectrum range, the higher the J SC The larger the J is, the more it is affected by the quality and thickness of the perovskite film. Therefore, broadening the absorption spectrum of the perovskite layer, improving the film quality, and optimizing the optimal thickness are the key to increasing J SC effective method.

[0076] (2) Open circuit voltage (V OC );

[0077] Under light conditions, the voltage when the device is in an open circuit (current is 0) is the open circuit voltage, and the unit is volts (V). OC It is mainly determined by the band gap of the perovskite material itself and the energy level difference between it and the transport layer. Therefore, adjusting the band gap of the perovskite layer and reducing the energy level difference between it and the transport layer is the key to increasing V OC effective method.

[0078] (3) Fill factor (FF);

[0079] FF is the maximum output power of the device (P mpp ) under the current (J mpp ) and voltage (V mpp ) and J SC With V OC The ratio of products.

[0080]

[0081] Reducing the series resistance of the device, increasing the parallel resistance, and improving the contact between layers can all increase FF.

[0082] (4) Power conversion efficiency (PCE);

[0083] PCE is the maximum output power of the device (P mpp ) and the incident light intensity (P light ) ratio is the most intuitive parameter to characterize device performance, which is expressed by J SC 、V OC , FF jointly decided.

[0084]

[0085] In summary, the present invention prepares the cathode interface layer based on DCNQA-PyBr and applies it to perovskite (such as Cs 0.15 FA 0.85 In a PbI3 system) solar cell module, the thickness of the DCNQA-PyBr cathode interface layer can be widened to 30 nm, which can ensure that the organic solar cell has a high energy conversion efficiency and can meet the industrial production requirement of an energy conversion efficiency greater than 15%. The higher thickness also reduces pinholes and defects in the cathode interface layer, making it easier to process.

[0086] The above are only preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several variations and improvements can be made without departing from the concept of the present invention. These should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A method for preparing a perovskite solar cell module, characterized in that: The following steps are involved: P1 scribing: Laser scribing is performed on the anode surface to vaporize the anode material and form a groove line P1; Preparation of hole transport layer: Two hole transport material solutions are coated on the laser-scribed anode surface and annealed separately to form a hole transport layer on the anode surface; Preparation of the perovskite layer: A precursor of a photoactive material solution is applied to the surface of the hole transport layer, and the solution is continuously spin-coated in two steps, low speed and high speed. During the high-speed spin coating, an anti-solvent is added to the substrate. After annealing, a perovskite film is obtained, and a perovskite layer is formed on the surface of the hole transport layer. The photoactive material used to prepare the perovskite layer is a metal halide perovskite, which is a cubic crystal material with a molecular formula of ABX3, wherein A is Cs + and FA + ; B is Pb 2+ , X is I - The specific chemical formula of the perovskite layer material is Cs 0.15 FA 0.85 PbI3; Preparation of electron transport layer: coating the surface of the perovskite layer with an electron transport material solution, and then removing the solvent to form an electron transport layer on the surface of the perovskite layer; Preparation of cathode interface layer: coating cathode interface material solution on the surface of electron transport layer, and forming cathode interface layer on the surface of electron transport layer after removing solvent; P2 scribing: Laser scribing is performed on the surface of the electron transport layer to vaporize the hole transport layer, perovskite layer, electron transport layer, and cathode interface layer materials and form groove lines P2; Cathode preparation: preparing a cathode on the surface of the cathode interface layer; P3 scribing: Laser scribing is performed on the cathode surface to vaporize the hole transport layer, perovskite layer, electron transport layer, cathode interface layer, and cathode material to form groove lines P3; the entire film layer is divided into sub-cells connected in series to form separate modules that block current conduction, thereby increasing the voltage and connecting the cells in series to obtain a perovskite solar cell module; P4 edge cleaning: Laser P4 edge cleaning is performed to remove all film layers at the edge of the substrate to form an insulating area, which will serve as the packaging area for subsequent perovskite solar cell modules.

2. The preparation method according to claim 1, characterized in that The material of the anode is indium tin oxide, and the material of the cathode is metal.

3. The preparation method according to claim 1, characterized in that The hole transport material used to prepare the hole transport layer is NiO X and 2PACz.

4. The preparation method according to claim 1, characterized in that The photoactive material is a cubic crystal CsI formed by crystallization of a mixture of CsI, MACl, FAI, PbI2 and PbCl2. 0.15 FA 0.85 The chemical molar ratio of PbI3, CsI, MACl, FAI, PbI2 and PbCl2 is 0.15:0.025:0.85:0.975:0.

025.

5. The preparation method according to claim 1, characterized in that When the cathode interface material used to prepare the cathode interface layer is a quinacridone derivative, the cathode interface material solution is a quinacridone derivative solution; the concentration of the quinacridone derivative solution is 7.5 mg / mL.

6. A perovskite solar cell module prepared according to the preparation method of claims 1 to 5, characterized in that: The invention comprises an anode, a hole transport layer, a perovskite layer, an electron transport layer, a cathode interface layer and a cathode which are stacked in sequence.

7. The perovskite solar cell assembly according to claim 6, characterized in that: The cathode interface material used to prepare the cathode interface layer is a quinacridone derivative, and the quinacridone derivative has a structure shown in Formula I: Formula I:

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