Organic semiconductor material based on asymmetric fused heterocycle and preparation method and application thereof
By designing organic semiconductor materials based on asymmetric fused heterocyclic rings, the problems of interface energy level matching and carrier recombination in perovskite solar cells were solved, achieving higher energy conversion efficiency and stability, and promoting the improvement of perovskite solar cell performance.
Patent Information
- Application Number
- CN202610039429.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-13
- Publication Date
- 2026-05-12
AI Technical Summary
In existing perovskite solar cells, traditional doped hole transport materials suffer from poor interface energy level matching and insufficient electronic properties, resulting in limited device performance degradation and carrier recombination suppression, making it difficult to meet industrialization requirements.
By using organic semiconductor materials based on asymmetric fused heterocycles, and by introducing O and S heteroatoms to regulate the surface work function and interface dipoles, a more ordered and compact monolayer is formed, which promotes carrier transport and suppresses nonradiative recombination.
The energy conversion efficiency has been improved. The short-circuit photocurrent density of the battery device reaches 26.18 mA cm-2, the open-circuit voltage is 1.167 V, the fill factor is 0.8531, and the photoelectric conversion efficiency reaches 26.09%, breaking through the performance bottleneck of traditional materials.
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Figure CN122011030A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of perovskite solar cell technology, and relates to the preparation of organic semiconductor materials, particularly to the application of an organic semiconductor material based on asymmetric fused heterocycles in inverted perovskite solar cells. Background Technology
[0002] Perovskite solar cells, as the most promising next-generation photovoltaic technology, rely heavily on the synergistic improvement of device efficiency and long-term stability for commercialization. In the cell structure, the hole transport layer plays a decisive role in these performance indicators. Traditional doped hole transport materials, due to the tendency of additives to cause device performance degradation, are no longer sufficient to meet industrialization requirements. Therefore, self-assembled monolayer materials, by forming an ultrathin and dense molecular capping layer, achieve highly efficient hole extraction without doping, providing a novel solution to overcome the stability bottleneck.
[0003] Among numerous SAM materials, hole transport layers based on [4-(9H-carbazole-9-yl)butylphosphonic acid (4PACz)] have become an important benchmark in this field. The carbazole group in its molecular structure provides hole transport properties, while the butylphosphonic acid chain ensures anchoring and self-assembly capabilities. Batteries using 4PACz as the hole transport layer significantly outperform traditional materials in terms of efficiency and stability, establishing a performance benchmark for SAM materials. However, with further research, 4PACz has revealed two key limitations: First, the energy level matching between the electronic properties of its molecular framework and the advanced perovskite light-absorbing layer is still not optimal, resulting in interfacial energy loss and limiting further improvements in open-circuit voltage; second, the single carbazole electron-donating group and alkyl chain connection mode are significantly insufficient in terms of interfacial dipole modulation and defect passivation capabilities, leading to limited suppression of non-radiative recombination at the perovskite interface.
[0004] Therefore, there is an urgent need in this field for a novel hole transport material that, while inheriting the advantages of undoped and highly stable SAM materials, can fundamentally overcome the performance bottleneck of 4PACz. An ideal new material should possess more precise energy level matching to minimize interfacial losses, stronger intramolecular charge transfer characteristics to improve hole extraction efficiency, and superior interfacial passivation capabilities to suppress carrier recombination. The purpose of this invention is precisely to provide such a novel self-assembled monolayer hole transport material that surpasses the performance level of 4PACz. Through innovative molecular structure design, it achieves synergistic optimization of interfacial energy level modulation and defect passivation, pushing the performance of perovskite solar cells towards their theoretical limits. Summary of the Invention
[0005] To address the shortcomings of existing technologies, this invention provides an organic semiconductor material based on asymmetric fused heterocyclic rings. This self-assembled monolayer organic semiconductor material uses fused rings as functional groups, which promotes the formation of a more ordered and densely packed monolayer of SAM molecules. It reduces pinhole defects: better coverage effectively reduces exposed points on the substrate. Furthermore, the introduction of O and S heteroatoms effectively modulates the surface work function and interfacial dipoles, thereby promoting carrier transport and suppressing surface nonradiative recombination, resulting in a significant improvement in energy conversion efficiency. Simultaneously, this invention provides a method for preparing this material and its application in the fabrication of inverted perovskite solar cells.
[0006] This invention is achieved through the following technical solution:
[0007] In a first aspect, the present invention provides an organic semiconductor material based on an asymmetric fused heterocycle, the chemical structural formula of which is shown below:
[0008] .
[0009] Secondly, the present invention provides a method for preparing the above-mentioned organic semiconductor material based on asymmetric fused heterocycles, comprising the following steps:
[0010] (1) Using benzocarbazole compound AH as the starting material, it is coupled with 1,4-dibromobutane to generate compound 2 or 6;
[0011] (2) To cause compound 2 or 6 to undergo a coupling reaction with triethyl phosphite to generate compound 3 or 7;
[0012] (3) Cause compound 3 or 7 to undergo a hydrolysis reaction to generate the final product 4 or 8;
[0013] The initial raw material, benzo[a]carbazole compound AH, is selected from the following compounds:
[0014]
[0015] The synthetic routes for compounds 4 and 8 are shown below, respectively:
[0016] .
[0017] Furthermore, in step (1), compound AH is mixed evenly with 1,4-dibromobutane, tetrabutylammonium bromide, potassium hydroxide and water, and reacted at 50~80℃ for 5~8h to generate compound 2 or 6.
[0018] Furthermore, in step (1), the molar ratio of the compound AH, 1,4-dibromobutane, tetrabutylammonium bromide and potassium hydroxide is 1:18~21:0.01~0.12:10~12; the ratio of potassium hydroxide to water is 1g:0.1~1.2mL.
[0019] Furthermore, in step (2), under argon protection, compound 2 or 6 is dissolved in triethyl phosphite and reacted at 150-180 °C for 10-15 h to generate compound 3 or 7.
[0020] Furthermore, in step (2), the molar ratio of compound 2 or 6 to triethyl phosphite is 1:12~20.
[0021] Further, in step (3), under argon protection, compound 3 or 7 is dissolved in 1,4-dioxane with trimethylbromosilane and reacted at room temperature for 12-18 h. The solvent is removed by vacuum distillation. The obtained solid is added to methanol in water and the reaction continues for 2-5 h. The precipitated solid is filtered and dried to obtain compound 4 or 8.
[0022] Furthermore, in step (3), the molar ratio of compound 3 or 7 to trimethylbromosilane is 1:7~11;
[0023] Thirdly, the present invention provides the application of the above-mentioned organic semiconductor material based on asymmetric fused heterocycles in the fabrication of inverted perovskite solar cells.
[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0025] 1. The self-assembled monolayer organic semiconductor material of this invention uses fused rings as functional groups, which can promote the formation of a more ordered and densely packed monolayer of SAM molecules. This reduces pinhole defects: better coverage effectively reduces exposed points on the substrate. Furthermore, the introduction of S heteroatoms can effectively regulate the surface work function and interfacial dipoles, thereby promoting carrier transport, suppressing surface nonradiative recombination, and effectively improving energy conversion efficiency.
[0026] 2. The application of the self-assembled monolayer organic semiconductor material provided by this invention as a hole transport layer in perovskite solar cells shows that the short-circuit photocurrent density of the battery device reaches 26.18 mA cm⁻¹. -2 With an open-circuit voltage of 1.167 V, a fill factor (FF) of 0.8531, and a photoelectric conversion efficiency of 26.09%, it has practical significance for improving the efficiency of perovskite solar cells. Attached Figure Description
[0027] Figure 1 The NMR spectrum of the compound of formula 4 prepared in this invention;
[0028] Figure 2 The NMR spectrum of the compound of formula 8 prepared in this invention;
[0029] Figure 3 JV curves of inverted perovskite solar cells prepared by self-assembling monolayers using the compound of formula 4 prepared in this invention.
[0030] Figure 4 JV curves of inverted perovskite solar cells prepared by self-assembling monolayers using the compound of formula 8 prepared in this invention. Detailed Implementation
[0031] The present invention will now be described in detail with reference to specific embodiments.
[0032] Example 1: Preparation of Compound 4
[0033]
[0034] The synthesis route is as follows:
[0035]
[0036] (1) Synthesis of compound 2:
[0037] Compound 1 (3 g, 9.27 mmol), 1,4-dibromobutane (21.5 mL, 177.24 mmol), tetrabutylammonium bromide (60 mg, 0.18 mmol), potassium hydroxide (5.5 g, 98.21 mmol), and water (5.5 mL) were added sequentially to a 100 mL two-necked flask. The mixture was heated to 70 °C and refluxed for 6 h. After the reaction solution cooled to room temperature, dichloromethane and water were added for extraction. The organic phase was distilled under reduced pressure. The crude product was subjected to column chromatography (eluent: petroleum ether / dichloromethane = 50 / 1~10 / 1) to give 3.8 g of a white solid, with a yield of 89.6%.
[0038] (2) Synthesis of compound 3:
[0039] Under argon protection, compound 2 (3.4 g, 7.43 mmol) and triethyl phosphite (25 mL, 144.89 mmol) were added sequentially to a 100 mL two-necked flask. The reaction mixture was heated to 165 °C and reacted for 12 h. After the reaction mixture cooled to room temperature, excess triethyl phosphite was distilled off under reduced pressure. The crude product was subjected to column chromatography (eluting agent: petroleum ether / dichloromethane = 10 / 1~1 / 4) to give 3.4 g of a white solid, with a yield of 88.77%.
[0040] (3) Synthesis of Equation 4:
[0041] Under argon protection, compound 3 (3.4 g, 6.59 mmol), trimethylbromosilane (7 ml, 53.98 mmol), and 15 mL of 1,4-dioxane were added sequentially to a 100 mL two-necked flask. The mixture was reacted at room temperature for 18 h. The solvent was removed by vacuum distillation, and the resulting solid was added sequentially to 15 mL of methanol and 30 mL of deionized water. The mixture was stirred for another 3 h to precipitate a solid. The solid was filtered and washed with water to give 2.7 g of a white product, with a yield of 89.1%.
[0042] The structural characterization data of compound 4 are as follows:
[0043] 1 H NMR (400 MHz, DMSO) δ 9.26 (d, J = 8.4 Hz, 1H), 9.11 – 9.03 (m,2H), 8.74 (d, J = 8.1 Hz, 1H), 8.32 (dd, J = 8.0, 1.2 Hz, 1H), 7.93 (d, J =8.3 Hz, 1H), 7.88 – 7.80 (m, 1H), 7.73 (dddd, J = 11.3, 8.4, 6.9, 1.3 Hz,2H), 7.62 (t, J = 7.5 Hz, 1H), 7.57 (t, J = 7.7 Hz, 1H), 7.44 (t, J = 7.5 Hz,1H), 4.90 (t, J = 7.6 Hz, 2H), 2.02 (p, J = 7.8 Hz, 2H), 1.86 – 1.69 (m, 2H), 1.69 – 1.54 (m, 2H).
[0044] Example 2: Preparation of Compound 8
[0045]
[0046] The synthesis route is as follows:
[0047]
[0048] (1) Synthesis of compound 6:
[0049] Compound 5 (3 g, 9.27 mmol), 1,4-dibromobutane (21.5 mL, 177.24 mmol), tetrabutylammonium bromide (60 mg, 0.18 mmol), potassium hydroxide (5.5 g, 98.21 mmol), and water (5.5 mL) were added sequentially to a 100 mL two-necked flask. The mixture was heated to 70 °C and refluxed for 6 h. After the reaction mixture cooled to room temperature, dichloromethane and water were added for extraction. The organic phase was distilled under reduced pressure. The crude product was subjected to column chromatography (eluent: petroleum ether / dichloromethane = 50 / 1~10 / 1) to give 3.8 g of a white solid, with a yield of 89.6%.
[0050] The structural characterization data of compound 6 are as follows:
[0051] 1 H NMR (400 MHz, DMSO) δ 8.87 (d, J = 56.7 Hz, 2H), 8.52 – 7.95 (m,6H), 7.57 (s, 4H), 4.93 (s, 2H), 3.57 (s, 2H), 2.03 (s, 4H).
[0052] (2) Synthesis of compound 7:
[0053] Under argon protection, compound 6 (3.4 g, 7.43 mmol) and triethyl phosphite (25 mL, 144.89 mmol) were added sequentially to a 100 mL two-necked flask. The reaction mixture was heated to 165 °C and reacted for 12 h. After the reaction mixture cooled to room temperature, excess triethyl phosphite was distilled off under reduced pressure. The crude product was subjected to column chromatography (eluting agent: petroleum ether / dichloromethane = 10 / 1~1 / 4) to give 3.4 g of a white solid, yield 88.77%.
[0054] (3) Synthesis of Equation 8:
[0055] Under argon protection, compound 7 (3.4 g, 6.59 mmol), trimethylbromosilane (7 ml, 53.98 mmol), and 15 mL of 1,4-dioxane were added sequentially to a 100 mL two-necked flask. The mixture was reacted at room temperature for 18 h. The solvent was removed by vacuum distillation, and the resulting solid was added sequentially to 15 mL of methanol and 30 mL of deionized water. The mixture was stirred for another 3 h to precipitate a solid. The solid was filtered and washed with water to give 2.7 g of a white product, with a yield of 89.1%.
[0056] The structural characterization data of compound Formula 8 are as follows:
[0057] 1H NMR (400 MHz, DMSO) δ 8.93 (d, J = 8.4 Hz, 1H), 8.87 (d, J = 8.8Hz, 1H), 8.32 (d, J = 8.0 Hz, 1H), 8.11 (d, J = 8.4 Hz, 2H), 8.00 (d, J = 9.0Hz, 1H), 7.83 (d, J = 8.0 Hz, 1H), 7.74 (dd, J = 8.3, 4.8 Hz, 2H), 7.62 –7.48 (m, 3H), 5.08 (t, J = 7.1 Hz, 2H), 2.09 (t, J = 7.7 Hz, 2H), 1.58 (ddd,J = 37.0, 16.4, 7.9 Hz, 4H).
[0058] Example 3
[0059] The nuclear magnetic resonance spectrum of compound 4, a self-assembled monolayer hole transport material prepared in Example 1, is shown below. Figure 1 As shown. This embodiment provides a perovskite solar cell prepared using compound formula 4 prepared in Example 1, according to the literature: M. Liu; L. Bi; W. Jiang; et al. Adv. Mater. 2023, 2304415. The test light source was AM 1.5 (solar simulator-Oriel 91160-1000, 300W), and data acquisition was performed using a Keithley 2400 digital source meter. The test results are shown in […]. Figure 3 The short-circuit photocurrent density of the battery device reached 26.12 mA cm⁻¹. -2 The open-circuit voltage is 1.17 V, the fill factor (FF) is 0.8502, and the photoelectric conversion efficiency reaches 25.99%.
[0060] Example 4
[0061] The nuclear magnetic resonance spectrum of compound 8, a self-assembled monolayer hole transport material prepared in Example 2, is shown below. Figure 2 As shown. This embodiment provides a perovskite solar cell prepared using compound formula 8 prepared in Example 2, according to the literature: M. Liu; L. Bi; W. Jiang; et al. Adv. Mater. 2023, 2304415. Test light source: AM 1.5 (solar simulator-Oriel 91160-1000, 300W), data acquisition used a Keithley 2400 digital source meter. Test results are shown in […]. Figure 4The short-circuit photocurrent density of the battery device reached 26.18 mA cm⁻¹. -2 The open-circuit voltage is 1.167 V, the fill factor (FF) is 0.8531, and the photoelectric conversion efficiency reaches 26.09%.
[0062] It should be further noted that the preparation methods of Examples 1 and 2 of this invention do not cover all the choices of reactant dosages and process conditions. In addition to the dosages and reaction conditions provided in the above examples, in step (1), the molar ratio of compound AH, 1,4-dibromobutane, tetrabutylammonium bromide, and potassium hydroxide can be selected within the range of 1:18~21:0.01~0.12:10~12, the ratio of potassium hydroxide to water can be selected within the range of 1g:0.1~1.2mL, and the reaction temperature and reaction time can be selected within the range of 50~80℃ and 5~8h. In step (2), the molar ratio of compound 2 or 6 to triethyl phosphite can be selected within the range of 1:12~20, and the reaction temperature and reaction time can be selected within the range of 150~180℃ and 10~15h. In step (3), the molar ratio of compound 3 or 7 to trimethylbromosilane can be selected within the range of 1:7 to 11, the reaction time at room temperature can be selected within the range of 12 to 18 h, and the continued reaction of the resulting solid with methanol and water can be selected within the range of 2 to 5 h. It is clear that the above description of the embodiments is only for illustrating the technical concept and features of the present invention, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. Those skilled in the art can obviously easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative effort. Therefore, the above embodiments cannot be used to limit the scope of protection of the present invention. All improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be covered within the scope of protection of the present invention.
Claims
1. An organic semiconductor material based on asymmetric fused heterocycles, characterized in that, The chemical structural formula is shown in formula (4) or formula (8) below: 。 2. The method for preparing an organic semiconductor material based on asymmetric fused heterocycles as described in claim 1, characterized in that, Includes the following steps: (1) Using benzocarbazole compound AH as the starting material, it is coupled with 1,4-dibromobutane to generate compound 2 or 6; (2) To cause compound 2 or 6 to undergo a coupling reaction with triethyl phosphite to generate compound 3 or 7; (3) Cause compound 3 or 7 to undergo a hydrolysis reaction to generate the final product compound 4 or 8; The initial raw material, benzo[a]carbazole compound AH, is selected from one of the following compounds: The synthetic routes for compounds 4 and 8 are shown below, respectively: 。 3. The method for preparing an organic semiconductor material based on asymmetric fused heterocycles according to claim 2, characterized in that: Step (1) involves mixing compound AH with 1,4-dibromobutane, tetrabutylammonium bromide, potassium hydroxide, and water until homogeneous, and reacting at 50-80°C for 5-8 hours to generate compound 2 or 6.
4. The method for preparing an organic semiconductor material based on asymmetric fused heterocycles according to claim 3, characterized in that: In step (1), the molar ratio of compound AH, 1,4-dibromobutane, tetrabutylammonium bromide and potassium hydroxide is 1:18~21:0.01~0.12:10~12; the ratio of potassium hydroxide to water is 1g:0.1~1.2mL.
5. The method for preparing an organic semiconductor material based on asymmetric fused heterocycles according to claim 2, characterized in that: Step (2) involves dissolving compound 2 or 6 in triethyl phosphite under argon protection and reacting at 150-180 °C for 10-15 h to generate compound 3 or 7.
6. The method for preparing an organic semiconductor material based on asymmetric fused heterocycles according to claim 5, characterized in that: In step (2), the molar ratio of compound 2 or 6 to triethyl phosphite is 1:12~20.
7. The method for preparing an organic semiconductor material based on asymmetric fused heterocycles according to claim 2, characterized in that: Step (3) involves dissolving compound 3 or 7 with trimethylbromosilane in 1,4-dioxane under argon protection and reacting at room temperature for 12-18 h. The solvent is removed by vacuum distillation, and the resulting solid is added to methanol in water. The reaction continues for 2-5 h, and the precipitated solid is filtered and dried to obtain compound 4 or 8.
8. The method for preparing an organic semiconductor material based on an asymmetric fused heterocycle according to claim 7, characterized in that: In step (3), the molar ratio of compound 3 or 7 to trimethylbromosilane is 1:7~11.
9. The application of the organic semiconductor material based on asymmetric fused heterocycles as described in claim 1 in the fabrication of inverted perovskite solar cells.