Y-type non-fullerene acceptor electron transport material driven by coordination supramolecular interaction and preparation method and application thereof

Abstract

The application belongs to the technical field of perovskite photovoltaic materials, and particularly relates to Y-type non-fullerene acceptor electron transport materials driven by coordination supramolecular action and a preparation method and application thereof. The application adopts high-polarity phenylroline and crown ether to replace the benzothiadiazole core of Y6, and develops two Y-type NFAs, Y-Phen and Y-CE. The use of Y-Phen and Y-CE as ETLs of perovskite solar cells can obtain laboratory power conversion efficiencies of 25.03% and 25.61% respectively, wherein the use of Y-CE as ETL obtains an authenticated power conversion efficiency of 25.59%, which is significantly higher than the power conversion efficiency (23.58%) of the device using Y6 as ETL. At the same time, the degradation rate of the optimized device to PCE is less than 10% after 1440 hours, and the device has excellent performance in the preparation of perovskite solar cells.

Description

Technical Field

[0001] This invention belongs to the field of perovskite photovoltaic materials technology, specifically relating to Y-type non-fullerene acceptor electron transport materials driven by coordination supramolecular interactions, their preparation methods, and applications. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Invert perovskite photovoltaic technology has attracted widespread attention due to its negligible hysteresis and high matching degree in tandem cells, gradually demonstrating great potential in terms of efficiency and stability. With the continuous optimization of organic-inorganic hybrid perovskite thin-film light-absorbing layers, the factors limiting the improvement of efficiency and stability of invert perovskite solar cells have mainly focused on interfaces, especially the interfaces between the perovskite layer and the charge transport layer, and between the transport layer and the electrodes. These interface problems mainly include interface defects between the active layer and the transport layer, severe mass diffusion and ion migration, and interface energy level mismatch.

[0004] Currently, the electron transport layer of trans-perovskites mainly uses fullerene C60. However, fullerenes suffer from problems such as weak chemical interactions with perovskites, low energy state matching between the fullerene electron transport layer and the perovskite active layer, and molecular disorder within the fullerene electron transport layer. Developing novel electron transport materials to replace fullerenes is the optimal choice to fundamentally overcome these problems. Conventional Y-type non-fullerenes possess characteristics such as high mobility and tunable energy levels, showing potential to replace fullerenes. However, the intermolecular interactions between conventional Y-type non-fullerene acceptors and perovskites are dispersed, resulting in interfacial energy disorder and limiting their potential to replace fullerenes. Introducing coordinating supramolecular interaction groups can drive the ordered assembly and arrangement of Y-type molecules at the interface, which is an effective way to overcome the above difficulties. Summary of the Invention

[0005] To address the problems in the prior art, this invention provides a Y-type non-fullerene acceptor electron transport material driven by coordination supramolecular interaction, its preparation method, and its application.

[0006] The objective of this invention will be achieved through the following technical solutions:

[0007] In a first aspect, the present invention provides a Y-type receptor material having a structure shown in any one of Formulas I to II:

[0008]

[0009] R1 and R2 are independently one of straight-chain or branched-chain alkyl groups of C6 to C50; W, X, Y, and Z are independently one of hydrogen, fluorine, chlorine, bromine, and iodine.

[0010] Furthermore, R1 and R2 are independently one of C6 to C20 straight-chain or cross-chain alkyl groups.

[0011] Furthermore, the receptor material described above is selected from one of the following structures:

[0012]

[0013] Secondly, the present invention provides a method for preparing the above-mentioned Y-type receptor material, wherein the synthesis of the structure of Formula I includes the following steps:

[0014] (1) Compound M1 reacts with LiAlH4 to give intermediate M2;

[0015] (2) Intermediate M2 reacts with 1,10-phenanthroline-5,6-dione to give intermediate M3;

[0016] (3) Intermediate M3, DMF, and POCl3 react to obtain intermediate M4;

[0017] (4) The intermediate M4 and IC end group react to obtain the structure shown in Formula I;

[0018] The reaction process is as follows:

[0019]

[0020] R1 and R2 are independently one of straight-chain or branched-chain alkyl groups of C6 to C50; W, X, Y, and Z are independently one of hydrogen, fluorine, chlorine, bromine, and iodine.

[0021] Further, in step (1), specifically: the Y intermediate core M1 is dissolved in the ultra-dry solvent tetrahydrofuran and added to a double-necked round-bottom flask under nitrogen protection. Then, a tetrahydrofuran solution of reducing agent LiAlH4 is added, and stirring is continued for 5-10 min. The mixture is then refluxed in an oil bath for 12 hours. Heating is stopped, and the mixture is cooled to 0°C in an ice bath. Water of equal volume to tetrahydrofuran is slowly added to the reaction system, stirred evenly, and then extracted with ethyl acetate. The organic phase is dried with anhydrous sodium sulfate for 2-5 hours. The solvent is removed by rotary evaporation, and the unpurified intermediate M2 is used directly in the next step of the reaction.

[0022] Furthermore, in step (1), the molar ratio of M1 to LiAlH4 is 7 to 10:1.

[0023] Further, in step (2), specifically: M2 is dissolved in a 1:1 volume ratio mixture of anhydrous ethanol and acetic acid, and 1,10-phenanthroline-5,6-dione is added. The reaction is carried out at 100°C for 8–10 hours. After cooling to room temperature, the mixture is extracted with water and ethyl acetate. The organic phase is dried over anhydrous sodium sulfate for 2–5 hours. The solvent is removed by rotary evaporation, and the crude product is purified by column chromatography to obtain intermediate M3.

[0024] Furthermore, in step (2), the molar ratio of M2 to 1,10-phenanthroline-5,6-dione is 1:1 to 2.

[0025] Further, in step (3), specifically: under nitrogen protection, M3 is dissolved in 1,2-dichloroethane and cooled to 0°C. After stirring for 20 minutes, DMF and POCl3 are added. The mixture is refluxed for 12 hours. Then, the mixture is cooled to room temperature, and an aqueous sodium acetate solution is added. Stirring continues for 1 hour. The reaction system is extracted with dichloromethane, and the organic phase is dried with anhydrous sodium sulfate for 2–5 hours. The crude product is subjected to column chromatography to obtain intermediate M4.

[0026] Further, in step (3), DMF and POCl3 are added, and the ratio of M3, DMF and POCl3 is 0.157 mmol: 0.1-1 mL: 1-3 mmol.

[0027] Further, in step (4), specifically: M4 and IC end-group raw materials are dissolved in toluene. Then BF3·OEt2 and acetic anhydride are added, and the mixture is stirred at room temperature for 30-45 minutes. Methanol is added dropwise to the reaction solution while stirring, and a large amount of black precipitate solid is obtained, which is the compound with the structure shown in Formula I.

[0028] Furthermore, in step (4), the molar ratio of M4 to IC end groups is 1:2.2~3.

[0029] Furthermore, in step (4), the volume ratio of BF3·OEt2 to acetic anhydride is 2.5 to 3.5:1, preferably 3:1.

[0030] The synthesis of Formula II structure includes the following steps:

[0031] (1) Compounds M7 and M8 react to give intermediate M9;

[0032] (2) Intermediate M9, DMF, and POCl3 react to obtain intermediate M10;

[0033] (3) The intermediate M10 and IC end group react to obtain the structure shown in Formula II;

[0034] The reaction process is as follows:

[0035]

[0036] R1 and R2 are independently one of straight-chain or branched-chain alkyl groups of C6 to C50; W, X, Y, and Z are independently one of hydrogen, fluorine, chlorine, bromine, and iodine.

[0037] Further, in step (1), specifically: M7 is dissolved in anhydrous ethanol, then M8 is added, and the reaction is carried out at 110°C for 8–10 hours. Then, the mixture is cooled to room temperature. Extraction is performed with water and ethyl acetate. The organic phase is dried over anhydrous sodium sulfate. The solvent is removed by rotary evaporation, and the crude product is subjected to column chromatography to obtain intermediate M9.

[0038] Furthermore, in step (1), the molar ratio of M7 to M8 is 1:1 to 1.2.

[0039] Further, in step (2), specifically: under nitrogen protection, M9 is dissolved in 1,2-dichloroethane and cooled to 0°C. After stirring for 20 minutes, DMF and POCl3 are added. The mixture is refluxed for 12 hours. Then, the mixture is cooled to room temperature, and an aqueous sodium acetate solution is added. Stirring continues for 1 hour. The reaction system is extracted with dichloromethane, and the organic phase is dried with anhydrous sodium sulfate for 2–5 hours. The crude product is subjected to column chromatography to obtain intermediate M10.

[0040] Furthermore, in step (3), the ratio of M9, DMF and POCl3 is 0.157 mmol: 0.1-1 mL: 1-3 mmol.

[0041] Further, in step (4), specifically: M10 and IC end-group raw materials are dissolved in toluene. Then BF3·OEt2 and acetic anhydride are added, and the mixture is stirred at room temperature for 30-45 minutes. Methanol is added dropwise to the reaction solution while stirring, and a large amount of black precipitate solid is obtained, which is the compound with the structure shown in Formula II.

[0042] Furthermore, in step (4), the molar ratio of M10 to IC end groups is 1:2.2~3.

[0043] Furthermore, in step (4), the volume ratio of BF3·OEt2 to acetic anhydride is 2.5 to 3.5:1, preferably 3:1.

[0044] Thirdly, the present invention provides the application of the above-mentioned Y-type acceptor material in the fabrication of perovskite solar cells.

[0045] Fourthly, the present invention provides a perovskite solar cell, comprising a substrate, a bottom electrode, a hole transport layer, a perovskite photovoltaic active layer, an electron transport layer, and a top electrode;

[0046] The electron transport layer includes the aforementioned Y-type acceptor material.

[0047] Fifthly, the present invention provides a method for preparing the above-mentioned perovskite solar cell, comprising sequentially disposing of the bottom electrode, hole transport layer, perovskite photovoltaic active layer, electron transport layer, and top electrode on a substrate.

[0048] Further, the preparation method includes: providing a substrate; forming a bottom electrode layer on one side surface of the substrate, forming a hole transport layer on the side surface of the bottom electrode layer opposite to the substrate, forming a perovskite photovoltaic active layer on the side surface of the hole transport layer opposite to the substrate, and forming an electron transport layer on the side surface of the perovskite photovoltaic active layer opposite to the substrate.

[0049] Furthermore, in the electron transport layer, the Y-type acceptor material is dissolved in a solvent and spin-coated onto the perovskite photovoltaic active layer, and the concentration of the Y-type acceptor material is 2-20 mg / mL, preferably 10 mg / mL.

[0050] The beneficial effects of the technical solution of this invention are mainly reflected in:

[0051] Currently, fullerene derivatives are widely used in high-efficiency electron transport layers (ETLs) in perovskite photovoltaics, but challenges remain in mitigating interfacial recombination losses and ensuring stable film morphology. Non-fullerene acceptors (NFAs), commonly used in organic photovoltaics, are a promising alternative to fullerene-based electron transport materials. However, the suboptimal performance of NFA-based perovskite photovoltaic devices requires customization through molecular engineering. Based on this, this invention employs o-phenanthroline and crown ether to replace the benzothiadiazole core of Y6, developing two Y-type NFAs, Y-Phen and Y-CE. These modifications promote the ordered assembly of molecules on the perovskite surface through supramolecular interactions, thereby optimizing interfacial energy arrangement, promoting efficient charge transport, improving molecular stacking, and effectively enhancing carrier dynamics. Laboratory power conversion efficiencies of 25.03% and 25.61% were achieved using Y-Phen and Y-CE as ETLs in perovskite solar cells, respectively, with the device using Y-CE as the ETL achieving a certified power conversion efficiency of 25.59%. These results are all significantly higher than the power conversion efficiency (23.58%) of the device when Y6 is used as the ETL. Furthermore, the optimized device exhibits a PCE degradation rate of less than 10% after 1440 hours, demonstrating excellent performance in the fabrication of perovskite solar cells. Attached Figure Description

[0052] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0053] Figure 1The hydrogen NMR spectrum of the Y-Phen molecule in Example 1 of this invention;

[0054] Figure 2 The 1H NMR spectrum of the Y-CE molecule in Example 1 of this invention;

[0055] Figure 3 Thermogravimetric analysis spectra of Y-Phen, Y-CE, and the comparative molecule Y6 in Example 1 of this invention;

[0056] Figure 4 The UV-Vis-NIR absorption curves of Y-Phen, Y-CE, and the comparative molecule Y6 in Example 1 of this invention are shown.

[0057] Figure 5 The electron mobility analysis curves of Y-Phen, Y-CE and the comparative molecule Y6 in Example 1 of this invention are shown.

[0058] Figure 6 This is a structural diagram of the perovskite solar cell prepared in Example 2 of the present invention;

[0059] Figure 7 The current-voltage curves of perovskite solar cells in Example 3 of the present invention, which respectively use Y-Phen, Y-CE and the comparative molecule Y6 as electron transport layers;

[0060] Figure 8 This is the certification report for the perovskite solar cell used by ETL in Embodiment 3 of the present invention;

[0061] Figure 9 The storage stability of the perovskite solar cell described in Example 3 of this invention at 65 degrees Celsius;

[0062] Figure 10 This refers to the stability of the perovskite solar cell described in Example 3 of the present invention under the maximum power output condition of 45 degrees. Detailed Implementation

[0063] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0064] Where specific experimental steps or conditions are not specified in the embodiments, they can be performed according to the conventional experimental steps or conditions described in the literature in this field. All raw materials or instruments used are commercially available conventional products, including but not limited to those used in the embodiments of this application.

[0065] In this embodiment, the Y6 molecule used was obtained through purchase, and its structural formula is as follows:

[0066]

[0067] Example 1: Preparation of non-fullerene acceptor (NFAs) Y-Phen and Y-CE materials

[0068] The synthetic route for Y-Phen is as follows:

[0069]

[0070] Synthesis of compound M2 (11,12-bis(2-octyldodecyl)-3,8-cuicoalkyl-11,12-dihydrothieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-5,6-diamine, hereinafter referred to as M2): The intermediate core Y is M1 (12,13-bis(2-octyldodecyl)-3,9-cuicoalkyl-12,13-dihydro-[1,2,5]... Thiadiazolo[3,4-e]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole (hereinafter referred to as M1) was dissolved in ultra-dry solvent tetrahydrofuran and added to a two-necked round-bottom flask under nitrogen protection. Then, a tetrahydrofuran solution of reducing agent LiAlH4 was added, with a molar ratio of M1 to LiAlH4 of 8.5:1. The mixture was stirred for 7.5 min, and then refluxed in an oil bath for 12 h. Heating was stopped, and the mixture was cooled to 0 °C in an ice bath. An equal volume of water to tetrahydrofuran was slowly added to the reaction system, and the mixture was stirred until homogeneous. The mixture was then extracted with ethyl acetate. The organic phase was dried over anhydrous sodium sulfate for 3.5 h. The solvent was removed by rotary evaporation to obtain intermediate M2, which was used directly in the next reaction without purification.

[0071] Synthesis of compound M3 (10,11-bis(2-octyldodecyl)-7,14-tetradecyl-10,11-dihydrodipyridino[3,2-a:2',3'-c]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[3,2-h]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[2,3-j]benzopyrazine, hereinafter M3): M2 was dissolved in a 1:1 volume ratio of anhydrous ethanol and acetic acid, and 1,10-phenanthroline-5,6-dione was added. The molar ratio of M2 to 1,10-phenanthroline-5,6-dione was 1:1.5. The reaction was carried out at 100 °C for 9.5 h. After cooling to room temperature, the mixture was extracted with water and ethyl acetate. The organic phase was dried with anhydrous sodium sulfate for 3.5 hours. The solvent was removed by rotary evaporation, and the crude product was purified by column chromatography to obtain intermediate M3.

[0072] Synthesis of compound M4 (10,11-bis(2-octyldodecyl)-7,14-tetradecyl-10,11-dihydrodipyridino[3,2-a:2',3'-c]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[3,2-h]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[2,3-j]benzopyrazine-8,13-dicarboxaldehyde, hereinafter referred to as M4): Under nitrogen protection, M3 was dissolved in 1,2-dichloroethane and cooled to 0°C. After stirring for 20 minutes, DMF and POCl3 were added. The ratio of M3, DMF, and POCl3 was 0.157 mmol: 0.55 mL: 2 mmol. The reaction was refluxed for 12 hours. Then, the mixture was cooled to room temperature, and an aqueous solution of sodium acetate was added. The mixture was stirred for another hour. The reaction system was extracted with dichloromethane, and the organic phase was dried with anhydrous sodium sulfate for 2–5 hours. The crude product was subjected to column chromatography to obtain intermediate M4.

[0073] Synthesis of compound Y-Phen: M4 and IC-terminated starting materials were dissolved in toluene in a ratio of 1:2.6. Then, BF3·OEt2 and acetic anhydride (volume ratio 3:1) were added, and the mixture was stirred at room temperature for 38 minutes. Methanol was then added dropwise while stirring to obtain a large amount of black precipitate solid Y-Phen. The 1H NMR spectrum of the Y-Phen molecule is shown below. Figure 1 As shown.

[0074] The synthetic route for Y-CE is as follows:

[0075]

[0076] Synthesis of compound M9 (26,27-bis(2-hexyldecyl)-3,23-eicosyl-6a,8,9,11,12,14,15,17,18,19a,26,27-dodecano-[1,4,7,10,13]pentoxacyclopentadecano[2,3-i]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[3,2-a]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[2,3-c]benzopyrazine, hereinafter referred to as M9): M7 (11,12-bis(2-hexyldecyl) M7 (2,3,5,6,8,9,11,12-dihydrothieno[2”,3”:4’,5’]thieno[2’,3’:4,5]pyrrolo[3,2-g]thieno[2’,3’:4,5]thieno[3,2-b]indole-5,6-dione, hereinafter referred to as M7) was dissolved in anhydrous ethanol, and then M8 (2,3,5,6,8,9,11,12,13a,17a-decahydrobenzo[b][1,4,7,10,13]pentoxane-15,16-diamine, hereinafter referred to as M8) was added. The molar ratio of M7 to M8 was 1:1.1. The reaction was carried out at 110 °C for 9 hours. Then, the mixture was cooled to room temperature. The mixture was extracted with water and ethyl acetate. The organic phase was dried over anhydrous sodium sulfate. The solvent was removed by rotary evaporation, and the crude product was subjected to column chromatography to give intermediate M9.

[0077] M10(26,27-bis(2-hexyldecyl)-3,23-eicosyl-6a,8,9,11,12,14,15,17,18,19a,26,27-dodecano-[1,4,7,10,13]pentoxanepentadecano[2,3-i]thieno[2”,3”:4',5']thieno[2',3':4,5]pyrrolo[3,2-a]thieno[2”,3”:4',5']thieno Synthesis of [2',3':4,5]pyrrolo[2,3-c]benzopyrazine-2,24-dicarboxaldehyde (hereinafter referred to as M10): Under nitrogen protection, M9 was dissolved in 1,2-dichloroethane and cooled to 0°C. After stirring for 20 minutes, DMF and POCl3 were added. The ratio of M3, DMF, and POCl3, and the ratio of M9, DMF, and POCl3 were 0.157 mmol:0.55 mL:2 mmol. The mixture was refluxed for 12 hours. Then, the mixture was cooled to room temperature, and an aqueous sodium acetate solution was added. The mixture was stirred for another hour. The reaction mixture was extracted with dichloromethane, and the organic phase was dried over anhydrous sodium sulfate for 3.5 hours. The crude product was purified by column chromatography to obtain intermediate M10.

[0078] Synthesis of compound Y-CE: M10 and IC-terminated starting materials were dissolved in toluene in a ratio of 1:2.6. Then, BF3·OEt2 and acetic anhydride (volume ratio 3:1) were added, and the mixture was stirred at room temperature for 38 minutes. Methanol was then added dropwise while stirring, yielding a large amount of black precipitate, which is compound Y-CE with the structure shown in Formula II. The 1H NMR spectrum of the Y-CE molecule is shown below. Figure 2 As shown.

[0079] The properties of the synthesized Y-Phen and Y-CE were compared with those of the comparative molecule Y6. The thermogravimetric analysis spectra and UV-Vis-NIR absorption curves are shown below. Figure 3 and Figure 4 As shown, the electron mobility analysis curve is as follows: Figure 5 As shown above, Y-Phen, Y-CE, and Y6 all exhibit good thermal stability, exceeding 200℃; Y-Phen, Y-CE, and Y6 all demonstrate significant near-infrared absorption properties; among them, the electron mobility of Y-Phen and Y-CE films is higher than that of Y6 molecules.

[0080] Example 2: Fabrication of Y-Phen and Y-CE as perovskite solar cell devices for ETL

[0081] The Y-Phen and Y-CE materials prepared in Example 1 were used as perovskite solar cell devices for ETL, and the specific preparation methods are as follows:

[0082] Pre-patterned ITO glass substrates were ultrasonically cleaned with a cleaning agent, deionized water, acetone, and isopropanol for 15 minutes each time. Subsequently, the cleaned ITO glass substrates were dried in an oven at 80°C for 24 hours and treated with O2 plasma for 30 minutes before use. Then, Cb2Naph SAM (1.5 mg / mL) was spin-coated onto the ITO glass substrate at 3000 rpm for 30 seconds, followed by annealing at 100°C for 10 minutes. A 1.4 M perovskite precursor solution was prepared by dissolving FAI, PbI2, and CsI in a DMF:DMSO solvent (volume ratio 4:1), with the formulation being FAI... 0.95 Cs 0.05PbI3 (FAI, PbI2, CsI molar ratio 0.95:0.05:3). 30 minutes before film deposition, 32.27 mg PbI2, 11.67 mg PbCl2, 9.38 mg MACl, and 1 mg pF-PEAI were added to 1 mL of this solution. 40 μL of the perovskite precursor solution was spin-coated at 5000 rpm for 50 seconds. Five seconds before the end of the process, 180 μL of chlorobenzene antisolvent was added to the center of the wetted film. The film was then annealed at 100 °C for 30 minutes. Subsequently, a PI solution (0.3 mg / mL, dissolved in IPA) was spin-coated onto the prepared perovskite at 3000 rpm for 30 seconds, and annealed at 100 °C for 10 minutes. NFAs (Y-Phen or Y-CE) were weighed under ambient conditions and dissolved in chlorobenzene solvent (NFAs concentration 10 mg / mL). The solution was stirred at 60°C for 30 minutes in an N2-filled glove box. The resulting solution was cooled to room temperature and spin-coated onto a perovskite film at 3000 rpm for 30 seconds. All spin-coating processes were performed in an N2-filled glove box with O2 and H2O concentrations below 5 ppm and the temperature controlled at approximately 20°C. Finally, the film was viewed through a metal mask (pore area 0.04 cm²). 2 In a high vacuum chamber (<2×10) -6 A 6 nm layer of BCP and a 100 nm layer of Ag are thermally evaporated in a perovskite (TOR) layer. Then, a 100 nm layer of MgF2 is thermally evaporated on the glass side of the device as an anti-reflection layer, thus obtaining a perovskite solar cell. Its structural diagram is shown below. Figure 6 As shown.

[0083] Comparative Example 1: Y6 as a perovskite solar cell device for ETL

[0084] Y6 was used to prepare perovskite solar cell devices for ETL. The preparation method was the same as in Example 2, except that NFAs were Y6 materials and the concentration of Y6 was 10 mg / mL.

[0085] Experiment Example 1: Performance Verification

[0086] In a nitrogen-filled glove box, an AAA-grade solar simulator (AM 1.5G, 100mW·cm⁻¹) was used. -2 The organic solar cells fabricated under irradiation were tested under optimal device conditions (test area 0.0289 cm²). 2 Voltage-current curves were tested, and the measured parameters are shown in Table 1. The current-voltage curves are as follows: Figure 7 As shown.

[0087] Table 1

[0088] ETL layer Open-circuit voltage Voc (V) Fill factor FF (%) <![CDATA[Short-circuit current density (mA cm -2 )]]> Light conversion efficiency (%) Y6 1.146 81.09 25.38 23.58 Y-Phen 1.168 84.27 25.42 25.03 Y-CE 1.176 85.41 25.50 25.61

[0089] As shown in Table 1, laboratory power conversion efficiencies of 25.03% and 25.61% can be achieved using Y-Phen and Y-CE as ETLs for perovskite solar cells, respectively. The device using Y-CE as the ETL achieved a certified power conversion efficiency of 25.59%. These results are significantly higher than the power conversion efficiency (23.58%) achieved using Y6 as the ETL.

[0090] Furthermore, the optimized devices using Y-Phen or Y-CE as the electron transport layer, when continuously heated and stored in a nitrogen-atmosphere glove box at 65°C, exhibited a PCE degradation of less than 10% after 1440 hours, demonstrating excellent performance in the fabrication of perovskite solar cells. However, the devices using Y6 as the electron transport layer showed a PCE degradation exceeding 20%.

[0091] The Y-CE prepared above was sent to a third party for efficiency verification as an ETL perovskite solar cell device, and a certified power conversion efficiency of 25.59% was obtained. Figure 8 ).

[0092] Y6, Y-Phen, and Y-CE, as perovskite solar cell devices fabricated by ETL, were used to track the efficiency trends of the devices under storage conditions of 65°C in an N2 glove box or under maximum power output conditions at 45°C and one solar intensity. The results show that under storage conditions of 65°C (… Figure 9 Or, under the condition of maximum power output at 45°C and one solar intensity ( Figure 10 The device stability of Y-Phen and Y-CE is better than that of Y6.

[0093] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A Y-type receptor material, characterized in that, It has the structure shown in Equation I: Formula I; R1 and R2 are independently one of C6 to C20 straight-chain or cross-chain alkyl groups; W, X, Y, and Z are independently one of hydrogen, fluorine, chlorine, bromine, and iodine.

2. The Y-type receptor material as described in claim 1, characterized in that, Selected from the following structures: 。 3. The method for preparing the Y-type receptor material according to claim 1, characterized in that, include: (1) Compounds M7 and M8 react to give intermediate M9; (2) Intermediate M9, DMF, and POCl3 react to obtain intermediate M10; (3) The intermediate M10 reacts with the IC end group to obtain the structure shown in Formula I; The reaction process is as follows: ； R1, R2, W, X, Y, and Z are as defined in claim 1.

4. The application of the Y-type acceptor material according to claim 1 in the fabrication of perovskite solar cells.

5. A perovskite solar cell, comprising a substrate, a bottom electrode, a hole transport layer, a perovskite photovoltaic active layer, an electron transport layer, and a top electrode; in, The electron transport layer comprises the Y-type acceptor material according to any one of claims 1-2.

6. A method for preparing the perovskite solar cell according to claim 5, characterized in that, include: The bottom electrode, hole transport layer, perovskite photovoltaic active layer, electron transport layer, and top electrode are sequentially disposed on the substrate.

7. The preparation method according to claim 6, characterized in that, include: Provide a base; A bottom electrode layer is formed on one side surface of the substrate, a hole transport layer is formed on the side surface of the bottom electrode layer opposite to the substrate, a perovskite photovoltaic active layer is formed on the side surface of the hole transport layer opposite to the substrate, and an electron transport layer is formed on the side surface of the perovskite photovoltaic active layer opposite to the substrate.

8. The preparation method according to claim 7, characterized in that, In the electron transport layer, the Y-type acceptor material is dissolved in a solvent and spin-coated onto the perovskite photovoltaic active layer, and the concentration of the Y-type acceptor material is 2~20 mg / mL.

9. The preparation method according to claim 8, characterized in that, The concentration of the Y-type receptor material is 10 mg / mL.

Images