Self-assembled monolayer material and use thereof
By introducing conjugated structures of intramolecular conformational lock structures or fused ring structures into self-assembled monolayer materials, the problems of insufficient material density and stability are solved, achieving efficient photoelectric conversion and improved stability.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SHENZHEN UNIVERSITY OF ADVANCED TECHNOLOGY
- Filing Date
- 2024-12-23
- Publication Date
- 2026-07-02
AI Technical Summary
Existing self-assembled monolayer materials have shortcomings in terms of density and stability, are easily affected by external factors, and have weak intermolecular interactions, which limits their application in scenarios with high stability requirements.
Introducing conjugated structures of intramolecular conformational lock structures or fused ring structures into self-assembled monolayer materials enhances intermolecular π-π interactions and coplanarity, and improves the compactness and stability of the material by forming strong interactions between the functional framework and the substrate.
It improves the film-forming properties and overall stability of self-assembled monolayer materials, enhances the carrier transport capacity and device efficiency of optoelectronic devices, and improves photoelectric conversion efficiency and stability.
Smart Images
Figure CN2024141590_02072026_PF_FP_ABST
Abstract
Description
A self-assembled monolayer material and its applications Technical Field
[0001] This invention relates to the field of new energy materials technology, specifically to a self-assembled monolayer material and its applications. Background Technology
[0002] Self-assembled monolayers (SAMs) are a technique that uses the spontaneous arrangement of molecules to form highly ordered monolayers on a substrate surface. This technique relies on the precise arrangement of organic molecules on a suitable substrate. These molecules typically possess specific functional groups and can form monolayers on the substrate surface through chemical bonds and weak intermolecular forces. Due to their high structural designability, controllable thickness, and excellent surface functionalization capabilities, self-assembled monolayers have become an important research focus in functional surface materials.
[0003] A typical self-assembled monolayer material consists of three parts: first, a functional framework that enables efficient carrier extraction, providing the necessary physical and chemical properties; second, linking groups that give the molecule the necessary degrees of freedom to adapt to the substrate surface; and finally, anchoring groups that can form strong covalent bonds with substrates such as conductive glass. Through the synergistic effect of these three parts, self-assembled monolayer materials can achieve precise control of surface properties at the molecular level, efficiently match with specific electrode materials, and optimize charge injection and transport efficiency.
[0004] However, the existing preparation process of self-assembled monolayers is easily affected by external factors such as humidity, temperature, and chemical reagents. Furthermore, the intermolecular interactions of self-assembled monolayers are insufficient, resulting in a loose molecular arrangement and inadequate monolayer density, thus reducing the overall stability and functionality of the material. In addition, the molecules in self-assembled monolayer materials are mainly connected by van der Waals forces, resulting in relatively weak adhesion to the substrate. This makes them prone to desorption or structural changes under long-term environmental exposure or mechanical stress, significantly limiting their application in scenarios requiring high stability.
[0005] In summary, existing self-assembled monolayer materials have significant shortcomings in terms of density and stability, and further improvements are urgently needed. Summary of the Invention
[0006] This invention introduces a heteroatom-containing conjugated structure with intramolecular conformational locking or fused ring structure into a self-assembled monolayer material with a functional framework, providing a self-assembled monolayer material and its applications.
[0007] Specifically, the present invention provides the following technical solutions:
[0008] In a first aspect, the present invention provides a self-assembled monolayer material comprising a functional framework, a linking group, and an anchoring group, wherein the linking group connects the functional framework and the anchoring group, and the linking group comprises an intramolecular conformational lock structure and / or a fused ring structure.
[0009] Preferably, the intramolecular conformational lock structure includes any one or more of the substituted or unsubstituted structural formulas shown in FIG1; wherein X is any one of O, S, Se, Te; Y is any one of F, Cl, O, S, C; R is any one of saturated or unsaturated cyclic, straight-chain, or branched carbon chain structures; d1 is the distance between X atom and Y atom, which is less than the sum of the van der Waals radii of X atom and Y atom.
[0010] Preferably, the torsion angle between the five-membered rings containing the X atom, or between the five-membered ring containing the X atom and the benzene ring containing the Y atom, is θ1, and its range is 0°≤θ1≤90°.
[0011] Preferably, the intramolecular conformational lock structure includes the substituted or unsubstituted structural formula shown in Figure 2; wherein, X is any one of O, S, Se, Te; Y is any one of F, Cl, O, S, C; Z is a H atom; R is any one of saturated or unsaturated cyclic, straight-chain, or branched carbon chain structures; d2 is the distance between Z atom and Y atom, which is less than the sum of the van der Waals radii of Z atom and Y atom.
[0012] Preferably, the torsion angle between the five-membered ring containing the X atom and the benzene ring containing the Y atom is θ2, which is in the range of 90°≤θ2≤180°.
[0013] Preferably, in the above-mentioned substituted structural formula, the substituent is located at the ortho and / or meta position of the X atom; the substituent is any one or more of H, F, Cl, Br, I, CN, NH2, OH, C1-C20 alkyl, and C1-C20 alkoxy.
[0014] In the aforementioned intramolecular conformational lock structure, the distances d1 and d2, and the torsion angles θ1 and θ2, are mathematical parameters describing the coplanarity of the molecular structure. Specifically, the distances d1 and d2 are key to proving that core interactions are formed between related elements to constitute a conformational lock, while the torsion angles θ1 and θ2 further characterize the coplanarity of the molecular conformation.
[0015] Preferably, the fused ring structure includes any one or more of the structural formulas shown in FIG3; wherein X1 is any one of S, Se, and Te; and X2 is any one of H, S, Se, Te, and N.
[0016] Preferably, the functional skeleton comprises any one or more of the following substituted or unsubstituted derivatives shown in FIG4: fluorene derivatives, carbazole derivatives, triphenylamine derivatives, diphenylamine derivatives, acridine derivatives, phenothiazine derivatives, phenoxazine derivatives, anthracene derivatives, anthraquinone derivatives, benzophenone derivatives, pentanol derivatives, naphthalenediimide derivatives, perylenediimide derivatives, tetraphenylethylene derivatives, triphenylethylene derivatives, benzene derivatives, triphenylborane derivatives, triphenylphosphine derivatives, perylene derivatives, benzophenone derivatives, and benzo[a]phenanthrene derivatives; in the substituted fluorene derivatives, carbazole derivatives, acridine derivatives, benzophenone derivatives, and phenothiazine derivatives, the substituents are located at positions 4 and / or 9; in the substituted triphenylamine derivatives and diphenylamine derivatives, the substituents are located at the para-N atom position.
[0017] Preferably, the linking group is directly connected to the functional skeleton by a covalent bond or connected by a covalent bond between spaced atoms; the linking group is directly connected to the anchoring group by a covalent bond or connected by a covalent bond between spaced atoms; the spaced atoms are any one or more of carbon atoms, oxygen atoms, nitrogen atoms, and sulfur atoms.
[0018] Preferably, the anchoring group includes any one or more of hydroxyl, carboxyl, phosphate, mercapto, amino, sulfonic acid, and borate groups.
[0019] In a second aspect, the present invention provides an application of a self-assembled monolayer material in the fabrication of optoelectronic devices, wherein the optoelectronic device uses the aforementioned self-assembled monolayer material as a hole transport layer, or uses the aforementioned self-assembled monolayer material to perform interface modification on the hole transport layer.
[0020] The beneficial effects of this invention are:
[0021] (1) The self-assembled monolayer material provided by this invention is composed of a functional framework, linking groups, and anchoring groups, wherein the linking groups are designed as conjugated structures with intramolecular conformational lock structures or fused ring structures. The heteroatoms in the conjugated structure can interact with the intermolecular carbon-hydrogen bonds, enhance molecular conjugation, strengthen the π-π interactions in molecular stacking, improve intermolecular forces and coplanarity, thereby improving the film-forming properties of the material and enhancing the overall compactness and stability.
[0022] (2) The self-assembled monolayer material provided by the present invention has high density and stability. The anchoring group therein can interact strongly with perovskite or metal oxide substrates. When the material is used as a hole transport layer material or for hole transport layer modification, the high density can enhance the carrier transport capability of the device, and the anchoring group can passivate perovskite defects, thereby improving the efficiency and stability of optoelectronic devices. Attached Figure Description
[0023] Figure 1 shows a structural formula of a conjugated structure containing heteroatoms with conformational lock in one embodiment;
[0024] Figure 2 shows a structural formula of a conjugated structure containing heteroatoms with conformational lock in one embodiment;
[0025] Figure 3 shows the structural formula of a conjugated structure containing heteroatoms with a fused ring in one embodiment;
[0026] Figure 4 shows the molecular structure of the functional host skeleton in one embodiment;
[0027] Figure 5 shows the molecular structure of the self-assembled monolayer material, where A is the functional framework, B is the linking group, and C is the anchoring group.
[0028] Figure 6 shows the synthesis reaction formula of BY-1, a self-assembled monolayer material in one embodiment;
[0029] Figure 7 shows the synthesis reaction formula of BY-2, a self-assembled monolayer material in one embodiment;
[0030] Figure 8 is a schematic diagram of a perovskite solar cell structure in one embodiment;
[0031] Figure 9 is a current density-voltage curve of a perovskite solar cell in one embodiment;
[0032] Figure 10 is a graph showing the stability of the photoelectric conversion efficiency of a perovskite solar cell in one embodiment.
[0033] Figure 11 is a schematic diagram of a perovskite solar cell structure in one embodiment. Detailed Implementation
[0034] The technical solution of this patent will be further described in detail below with reference to specific embodiments. It should be noted that the following detailed descriptions are exemplary 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.
[0035] As shown in Figure 5, the present invention provides a self-assembled monolayer material comprising a functional framework A (circular), a linking group B (rectangular), and an anchoring group C (arrow), wherein the linking group is a heteroatom-containing conjugated structure with an intramolecular conformational lock structure or a fused ring structure, and the anchoring group can interact with a perovskite or metal oxide substrate.
[0036] Example 1: Synthesis and characterization of self-assembled monolayer material BY-1
[0037] (1) As shown in Figure 6, compound 1, compound 2, Pd(PPh3)4, and potassium carbonate were placed in a dry Schlenk reaction flask, with addition amounts of 1 eq, 1 eq, 0.05 eq, and 2.5 eq, respectively. The reaction flask was evacuated and then purged with nitrogen gas, repeated three times to ensure an inert atmosphere. A mixed solvent of tetrahydrofuran and water at a volume ratio of 7:1 was then added, and the mixture was stirred in an oil bath at 80°C for 3 hours until equilibrium was reached. After the reaction cooled to room temperature, the palladium catalyst was removed by silica gel chromatography, the reaction solution was washed with water, and extracted with ethyl acetate to obtain a yellow solid crude product. The crude product was used directly in the next reaction without purification.
[0038] (2) The crude product was dissolved in a mixture of tetrahydrofuran and methanol at a volume ratio of 5:1, and 10 eq of potassium hydroxide was added. The mixture was stirred at 75°C for 12 h. After the reaction was completed, the mixture was acidified to a weakly acidic state with 1M hydrochloric acid solution and extracted with dichloromethane. The organic phase was collected and the solvent was removed by rotary evaporation. The mixture was then purified by silica gel column chromatography and finally dried under vacuum to obtain the self-assembled monolayer material BY-1.
[0039] Results: The self-assembled monolayer material BY-1 was an orange-red solid with the chemical formula C. 31 H 25 NO4S, yield 72%. BY-1 molecules crystallize easily, forming triclinic crystals with space group [missing information]. α = 85.211°(2), β = 76.945°(2), γ = 70.398°(2), and the unit cell volume is
[0040] Product BY-1 1 The H nuclear magnetic resonance spectrum signal is... 1 H NMR (400MHz, Chloroform-d, δ (ppm)): δ8.15-8.09 (m, 2H), 7.72 (d, J = 8.4Hz, 2H), 7.49-7.39 (m, 3H), 7.21 (d, J=3.8Hz, 1H), 7.11 (d, J=8.8Hz, 4H), 6.95 (d, J=8.4Hz, 2H), 6.92-6.82 (m, 4H), 3.83 (s, 6H).
[0041] Example 2: Synthesis and Characterization of Self-Assembled Monolayer Material BY-2
[0042] As shown in Figure 7, the synthesis steps of the self-assembled monolayer material BY-2 are basically the same as those of BY-1, except that compounds 3 and 4 are used as reactants.
[0043] Results: The self-assembled monolayer material BY-2 was an orange-red solid with a mass of 116 mg and a yield of 63%. BY-2 possesses an intramolecular conformational lock structure, its molecules cannot crystallize, it has strong self-film-forming properties, and it is easy to uniformly coat and form a dense film.
[0044] Product BY-2 1 The H nuclear magnetic resonance spectrum signal is... 1 H NMR (400MHz, Chloroform-d, δ (ppm)): δ7.8 (d, J=4.2Hz, 1H), 7.8-7.7 (m, 1H), 7.2 (d, J=4.0Hz, 1H), 7.0 (dd, J=11.8, 8.8Hz, 4H), 6.8 (dd, J=14.7, 9.0Hz, 4H), 6.7 (dd, J=12.6, 7.0Hz, 1H), 4.4 (d, J=12.8Hz, 4H), 3.8 (s, 5H), 3.7 (s, 1H).
[0045] Example 3: Application of self-assembled monolayer materials BY-1 and BY-2
[0046] Self-assembled monolayer materials BY-1 and BY-2 were dissolved in ethanol to prepare precursor solutions with a concentration of 0.5-1 mg / mL. 50-100 μL of the precursor solution was then uniformly spin-coated onto a surface with an area of 2.25-6 cm². 2 On an indium tin oxide (ITO) glass substrate, a spin-coating speed of 3000 rpm and a spin-coating time of 30 s were set. After spin-coating, the sample was annealed at 100 °C for 10 min to form a hole transport layer on the ITO glass substrate. Then, a perovskite solar cell was fabricated according to the structure shown in Figure 8, which, from bottom to top, consists of a substrate, a transparent oxide electrode, a hole transport layer, a photoactive layer, an electron transport layer, a hole blocking layer, and a metal electrode.
[0047] Results: Figure 9 shows the current density-voltage curve of the perovskite solar cell, and Table 1 shows the photovoltaic data of perovskite solar cell devices based on different self-assembled monolayer materials.
[0048] Table 1. Photovoltaic data of perovskite solar cell devices based on different SAMs
[0049] It can be seen that the photoelectric conversion efficiency of perovskite solar cells using BY-1 and BY-2 as hole transport layers reached 25.09% and 26.04%, respectively, which were significantly higher than the control group using MeO-2PACz and Me-4PACz. This indicates that BY-1 and BY-2 materials have a stronger ability to promote the conversion of light energy into electrical energy.
[0050] Furthermore, the open-circuit voltage of perovskite solar cells based on the self-assembled monolayer materials BY-1 and BY-2 was significantly higher than that of the MeO-2PACz and Me-4PACz control groups, indicating that BY-1 and BY-2 materials can effectively reduce voltage loss, thereby improving the overall efficiency of the cells. Simultaneously, the BY-1 and BY-2 groups exhibited higher short-circuit current densities, demonstrating superior photocurrent generation capabilities and enhancing the cell's output power. Meanwhile, the increased fill factor further demonstrates that perovskite solar cells based on BY-1 and BY-2 can achieve higher power output.
[0051] Figure 10 shows the results of maximum power point stability tests on perovskite solar cells of different material groups under a solar simulator. It can be seen that after 500 hours of continuous illumination, the photoelectric conversion efficiency of perovskite solar cells based on MeO-2PACz and Me-4PACz significantly decreased, while the perovskite cells based on BY-1 and BY-2 remained stable without significant degradation. This indicates that BY-1 and BY-2 exhibit superior light stability compared to traditional MeO-2PACz and Me-4PACz materials.
[0052] What needs to be understood is:
[0053] Firstly, the above embodiments, using BY-1 and BY-2 as examples, introduce the structure and synthesis method of self-assembled monolayer materials. However, the technical solution provided by this invention has broad applicability. In practical applications, any one or more of the substituted or unsubstituted structural formulas shown in Figure 1 or Figure 2 can be used as intramolecular conformational locking structures, or any one or more of the structural formulas shown in Figure 3 can be used as fused ring structures to form connecting groups based on intramolecular conformational locking structures and / or fused ring structures, thereby synthesizing self-assembled monolayer materials, improving the film-forming properties of the material, and enhancing the overall density and stability. Alternatively, any one or more of the substituted or unsubstituted structural formulas shown in Figure 4 can be used as functional frameworks; any one or more of hydroxyl, carboxyl, phosphate, mercapto, amino, sulfonic acid, and boric acid groups can be used as anchoring groups; different connection methods can be used to connect the connecting groups and anchoring groups, and the connecting groups and functional frameworks, thereby synthesizing self-assembled monolayer materials, improving the efficiency and stability of optoelectronic devices obtained based on the material. These should not be considered limitations of this application.
[0054] Secondly, the above embodiments use perovskite solar cells as an example to introduce the application of self-assembled monolayer materials in optoelectronic devices. In practical applications, the self-assembled monolayer materials provided in this application can also be used in other optoelectronic device structures, such as organic solar cells, quantum dot solar cells and other single-junction thin-film solar cells; organic / perovskite tandem solar cells, all-perovskite tandem solar cells, perovskite / crystalline silicon tandem solar cells and other tandem solar cells; or perovskite light-emitting diodes, etc. This should not be construed as a limitation of this application.
[0055] Third, the above embodiments use self-assembled monolayer materials as hole transport layer materials in solar cells as an example to introduce the application of self-assembled monolayer materials in optoelectronic devices. In practical applications, the self-assembled monolayer materials provided in this application can also be used for interface modification on the basis of the original hole transport layer. This should not be construed as a limitation of this application.
[0056] Fourth, the above embodiments use the structure of substrate / transparent oxide electrode / hole transport layer / photoactive layer / electron transport layer / hole blocking layer / metal electrode as an example to introduce the application of self-assembled monolayer materials in optoelectronic devices. In practical applications, they can also be used in other battery structures shown in Figure 11: 1) substrate / SAM / perovskite / electron transport layer / electron; 2) substrate / electron transport layer / perovskite / SAM / electron; 3) substrate / SAM / organic light-absorbing layer / electron transport layer / electron; 4) substrate / electron transport layer / organic light-absorbing layer / SAM / electron; 5) substrate / hole transport layer / SAM / perovskite / electron transport layer / electron; 6) substrate / hole transport layer / SAM / organic light-absorbing layer / electron transport layer / electron. This should not be construed as a limitation of this application.
[0057] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.
Claims
1. A self-assembled monolayer material, characterized in that, It includes a functional skeleton, a linking group, and an anchoring group, wherein the linking group connects the functional skeleton and the anchoring group, and the linking group includes an intramolecular conformational lock structure and / or a fused ring structure.
2. The SAM material of claim 1, wherein The intramolecular conformational lock structure includes any one or more of the following structural formulas, which are substituted or unsubstituted: Where X is any one of O, S, Se, and Te; Y can be any one of F, Cl, O, S, and C; R is any one of saturated or unsaturated cyclic, straight-chain or branched carbon chain structures; d1 is the distance between atom X and atom Y, which is less than the sum of the van der Waals radii of atom X and atom Y.
3. The SAM material of claim 2, wherein The twist angle between the five-membered rings containing atom X, or between the five-membered ring containing atom X and the benzene ring containing atom Y, is θ1, and its range is 0°≤θ1≤90°.
4. The SAM material of claim 1, wherein The intramolecular conformational lock structure includes a substituted or unsubstituted structure formula as follows: Where X is any one of O, S, Se, and Te; Y can be any one of F, Cl, O, S, and C; Z represents an H atom; R is any one of saturated or unsaturated cyclic, straight-chain or branched carbon chain structures; d2 is the distance between the Z atom and the Y atom, which is less than the sum of the van der Waals radii of the Z atom and the Y atom.
5. The SAM material of claim 4, wherein The twist angle between the five-membered ring containing atom X and the benzene ring containing atom Y is θ2, which has a range of 90°≤θ2≤180°.
6. The SAM material according to any one of claims 2 to 5, wherein In the substituted structural formula, the substituent is located at the ortho and / or meta position of the X atom; the substituent is any one or more of H, F, Cl, Br, I, CN, NH2, OH, C1-C20 alkyl, and C1-C20 alkoxy.
7. The SAM material of any one of claims 1-5, wherein, The fused ring structure includes any one or more of the following structural formulas: Where X1 is any one of S, Se, and Te; X2 is any one of H, S, Se, Te, and N.
8. The SAM material of claim 7, wherein, The functional framework includes any one or more of the following: substituted or unsubstituted fluorene derivatives, carbazole derivatives, triphenylamine derivatives, diphenylamine derivatives, acridine derivatives, phenothiazine derivatives, phenotoxazine derivatives, anthracene derivatives, anthraquinone derivatives, fentanyl ketone derivatives, piracene derivatives, naphthalene diimide derivatives, piracene diimide derivatives, tetraphenylethylene derivatives, triphenylethylene derivatives, benzene derivatives, triphenylborane derivatives, triphenylphosphine derivatives, perylene derivatives, benzophenone derivatives, and benzo[a]phenanthrene derivatives; In the substituted fluorene derivatives, carbazole derivatives, acridine derivatives, thionone derivatives, benzophenone derivatives, and phenothiazine derivatives, the substituents are located at positions 4 and / or 9. In the substituted triphenylamine derivatives and diphenylamine derivatives, the substituents are located at the N atom para position.
9. The SAM material of claim 8, wherein The linking group is directly connected to the functional skeleton by a covalent bond or connected by a covalent bond between spaced atoms; the linking group is directly connected to the anchoring group by a covalent bond or connected by a covalent bond between spaced atoms; the spaced atoms are any one or more of carbon atoms, oxygen atoms, nitrogen atoms, and sulfur atoms.
10. The SAM material of claim 8, wherein The anchoring group includes any one or more of the following: hydroxyl, carboxyl, phosphate, mercapto, amino, sulfonic acid, and borate.
11. Use of a self-assembled monolayer material in the manufacture of an optoelectronic device, characterized in that The optoelectronic device uses the self-assembled monolayer material as the hole transport layer according to any one of claims 1-10, or uses the self-assembled monolayer material as the interface material of any one of claims 1-10 to modify the hole transport layer.