Discotic liquid crystal charge transfer complex, and preparation method and application thereof

Abstract

This invention relates to the field of liquid crystal materials technology, and particularly to a disc-shaped liquid crystal charge transfer composite, its preparation method, and its applications. The preparation method provided by this invention includes mixing 2-methyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene, 2,4,7-trinitro-9-fluorenone, and a solvent, then removing the solvent from the resulting mixture to obtain a disc-shaped liquid crystal charge transfer composite precursor. The precursor is then subjected to melt treatment, cooling, annealing, and quenching to obtain a disc-shaped liquid crystal charge transfer composite with a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a bicontinuous Gyroid phase. The cooling and annealing temperatures are 30-45°C. The disc-shaped liquid crystal charge transfer composite of this invention possesses a three-dimensional interpenetrating, continuous, and isotropic network structure, exhibiting excellent transport performance.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal materials technology, and in particular to a disk-shaped liquid crystal charge transfer composite, its preparation method, and its application. Background Technology

[0002] Since their discovery in the early 20th century, liquid crystal materials have been widely used in display technology, optoelectronic devices, sensors, and solar cells. As a material exhibiting both fluidity and order, liquid crystals possess unique physical and optical properties that have secured their important position in modern electronics and optoelectronics. The properties of liquid crystals are primarily influenced by their molecular structure, particularly their self-assembly behavior and the formation and transformation of liquid crystal phases. The arrangement of liquid crystal molecules directly affects their photoelectric properties, especially in applications requiring three-dimensional electron transport networks and high-efficiency photoelectric performance, where traditional liquid crystal materials face significant challenges.

[0003] Currently, research on liquid crystal materials mainly focuses on several common liquid crystal phases, including nematic, columnar, and lamellar phases. Nematic liquid crystals exhibit a certain directional molecular arrangement, but the molecules are spatially disordered, thus limiting their photoelectric properties. Columnar liquid crystals possess a degree of order in molecular packing, but their structure remains limited to two-dimensional or quasi-one-dimensional. Lamellar liquid crystals exhibit one-dimensional molecular order, but still cannot meet the requirements of three-dimensional structures. These traditional liquid crystal phases have significant shortcomings in terms of molecular packing integrity, electron transport efficiency, and photoelectric conversion performance, making them unsuitable for the requirements of modern electronic technology for efficient three-dimensional electron transport networks.

[0004] In recent years, bicontinuous phases, as structures formed by three-dimensional space segmented by triple-period minimal surfaces (TPMS), have demonstrated advantages such as high order, strong three-dimensional connectivity, and high symmetry, providing efficient three-dimensional channels for electron and light transport. They have been extensively studied in block copolymers, lyotropic liquid crystal systems, and mesoporous materials. However, in thermotropic liquid crystal systems, the formation of bicontinuous phases faces numerous challenges, including the mismatch between rigid and flexible molecular structures, limitations in microphase separation scale, and difficulties in regulating intermolecular interactions. Their occurrence frequency is far lower than in lyotropic liquid crystal systems. This is especially true in discoid liquid crystals like ethylene, where the formation of bicontinuous cubic phases is even more challenging. Discoid liquid crystal molecules typically consist of a planar rigid aromatic core and peripheral flexible side chains. Their self-assembly behavior is mainly dominated by π-π stacking and van der Waals interactions between alkyl chains, tending to form low-dimensional ordered structures such as nematic, columnar, or layered phases. While these low-dimensional structures exhibit certain performance advantages in specific directions, their three-dimensional transport capabilities are limited, making it impossible to effectively construct continuous, isotropic three-dimensional transport networks.

[0005] Therefore, developing a liquid crystal material that can achieve stable self-assembly in three-dimensional space and has efficient transmission performance has become a key research direction in the field of liquid crystal materials. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a disk-shaped liquid crystal charge transfer composite, its preparation method and application. The disk-shaped liquid crystal charge transfer composite of the present invention has a three-dimensional interpenetrating, continuous and isotropic network structure with excellent transport performance.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for preparing a disc-shaped liquid crystal charge transfer composite, comprising the following steps: After mixing the electron donor, electron acceptor and solvent, the solvent in the resulting mixture is removed to obtain a disk-shaped liquid crystal charge transfer complex precursor. The disk-shaped liquid crystal charge transfer composite precursor was sequentially subjected to melt treatment, cooling, annealing and quenching to obtain the disk-shaped liquid crystal charge transfer composite. The electron donor comprises 2-methyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene; The electron acceptor includes 2,4,7-trinitro-9-fluorenone; The disk-shaped liquid crystal charge transfer complex has a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a dual continuous Gyroid phase. The target temperature for cooling is 30~45℃, and the annealing temperature is 30~45℃.

[0008] Preferably, the molar ratio of the electron donor to the electron acceptor is (1~4):1.

[0009] Preferably, the mass ratio of the solvent to the total mass of the electron donor and electron acceptor is (5~10):1.

[0010] Preferably, the melting temperature is 10°C or higher than the clearing point of the disk-shaped liquid crystal charge transfer composite precursor, and the holding time of the melting is 30-60 minutes.

[0011] Preferably, the cooling rate is 2~10℃ / min.

[0012] Preferably, the annealing holding time is 24~36h.

[0013] The present invention also provides a disk-shaped liquid crystal charge transfer complex prepared by the preparation method described above, wherein the disk-shaped liquid crystal charge transfer complex has a three-dimensional interpenetrating, continuous and isotropic periodic network structure of a dual continuous Gyroid phase.

[0014] Preferably, the characteristic diffraction peaks of the XRD diffraction pattern of the disk-shaped liquid crystal charge transfer composite are (211), (220) and (321).

[0015] The present invention also provides the application of the disk-shaped liquid crystal charge transfer composite described in the above technical solution in optoelectronic devices, wherein the disk-shaped liquid crystal charge transfer composite serves as a carrier transport functional material in optoelectronic devices.

[0016] Preferably, the optoelectronic device includes an organic solar cell or an organic field-effect transistor.

[0017] This invention provides a method for preparing a disc-shaped liquid crystal charge transfer composite, comprising the following steps: After mixing the electron donor, electron acceptor and solvent, the solvent in the resulting mixture is removed to obtain a disk-shaped liquid crystal charge transfer complex precursor. The disk-shaped liquid crystal charge transfer composite precursor was sequentially subjected to melt treatment, cooling, annealing and quenching to obtain the disk-shaped liquid crystal charge transfer composite. The electron donor comprises 2-methyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene; The electron acceptor includes 2,4,7-trinitro-9-fluorenone; The disk-shaped liquid crystal charge transfer complex has a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a dual continuous Gyroid phase. The target temperature for cooling is 30~45℃, and the annealing temperature is 30~45℃.

[0018] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: 1) This invention breaks the structural constraints of nematic or columnar phase formation in disk-shaped liquid crystals, and can stably obtain a double continuous Gyroid (DG) phase structure in disk-shaped liquid crystal systems. This breaks through the traditional structural mode of disk-shaped liquid crystals being mainly limited to nematic, columnar, or layered phases. The main reason for this is that the electron donor and electron acceptor in this invention form a charge transfer complex, which introduces significant intermolecular dipole-dipole interactions and space-filling constraints. This breaks the original self-assembly mode of disk-shaped molecules dominated by simple π-π stacking, thus providing the necessary conditions for the formation of a three-dimensional interpenetrating, continuous, and isotropic network structure. 2) Significantly improved transport performance: The DG phase formed by the disk-shaped liquid crystal charge transfer composite of the present invention has a three-dimensional interpenetrating, continuous and isotropic network structure, which can construct continuous transport channels in the bulk phase of the material. Compared with the existing columnar liquid crystal system, which only has one-dimensional transport capability along the column axis, it has significant advantages in charge, energy or molecular transport. The main reason is that by controlling the side chain length and designing the thermally induced self-assembly path (controlling the side chain length is necessary for the appearance of a bicontinuous phase; and the appearance of a bicontinuous phase requires temperature variation to induce self-assembly behavior in the composite, thereby controlling the appearance of the bicontinuous phase), the system enters the stable region of the bicontinuous cubic phase in the liquid crystal phase region, rather than falling into a low-dimensional ordered phase state, thus improving the transport dimension from the structural intrinsics. 3) The preparation method described in this invention has the advantages of simple process, high reproducibility and strong structural controllability. The preparation method does not require complex multi-block molecular design or polymer synthesis steps. It can achieve the construction of complex three-dimensional phases simply by mixing electron donors and electron acceptors in a solvent and combining solvent removal and thermal induction treatment (melting, cooling, annealing and quenching). The main reason is that this invention adopts a small molecule charge transfer composite strategy. Its self-assembly process is mainly dominated by non-covalent interactions. The system has good tolerance to processing conditions and is suitable for large-scale preparation and process scale-up. 4) The annealing treatment in the preparation method of the present invention can improve the structural reliability of the disk-shaped liquid crystal charge transfer composite under practical application conditions, giving it good thermal stability and reversibility. The structure remains stable during multiple heating and cooling cycles and does not undergo irreversible decomposition; thus improving its thermal stability and reversibility.

[0019] The disk-shaped liquid crystal charge-transfer composite prepared by the method described in this invention exhibits excellent application adaptability in the fields of optics, electronics, and functional materials. Its three-dimensional periodic network structure provides a structural basis for constructing isotropic photonic structures, continuous current-carrying channels, and multiphase transport networks, effectively overcoming the inherent limitations of existing liquid crystal materials in terms of orientation dependence and structural dimensions. This enables its successful application in high-efficiency optoelectronic functional materials. This effect stems from the synergistic effect of charge transfer, molecular structure design, and thermally induced self-assembly pathways in the overall technical solution of this invention.

[0020] In summary, by introducing a charge transfer recombination strategy, this invention achieves the controllable construction and stable regulation of a dual continuous Gyroid phase (dual continuous cubic phase) structure in a disk-shaped liquid crystal system. It outperforms existing technologies in terms of structural dimensions, transmission performance, and process feasibility, demonstrating significant technological advancement. Attached Figure Description

[0021] Figure 1 The image shows the polarized texture of the disk-shaped liquid crystal charge transfer composite described in Example 1. Figure 2 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite described in Example 1. Figure 3 The image shows the polarized texture of the disk-shaped liquid crystal charge transfer composite described in Example 2. Figure 4 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite described in Example 2. Figure 5 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite described in Example 3. Figure 6 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite described in Example 4. Figure 7 The image shows the polarized texture of the disk-shaped liquid crystal charge transfer composite described in Comparative Example 1. Figure 8 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite described in Comparative Example 1. Figure 9 The image shows the polarized texture of the disk-shaped liquid crystal charge transfer composite described in Comparative Example 2. Figure 10 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite described in Comparative Example 2. Figure 11 The image shows the polarized texture of the disk-shaped liquid crystal charge transfer composite described in Comparative Example 3. Figure 12 This is a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite described in Comparative Example 3. Detailed Implementation

[0022] This invention provides a method for preparing a disc-shaped liquid crystal charge transfer composite, comprising the following steps: After mixing the electron donor, electron acceptor and solvent, the solvent in the resulting mixture is removed to obtain a disk-shaped liquid crystal charge transfer complex precursor. The disk-shaped liquid crystal charge transfer composite precursor was sequentially subjected to melt treatment, cooling, annealing and quenching to obtain the disk-shaped liquid crystal charge transfer composite. The electron donor includes 2-methyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene (T5E1, molecular formula C... 44 H 62 O7); The electron acceptor includes 2,4,7-trinitro-9-fluorenone (TNF, molecular formula C... 17 H5N3O7); The disk-shaped liquid crystal charge transfer complex has a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a dual continuous Gyroid phase. The target temperature for cooling is 30~45℃, and the annealing temperature is 30~45℃.

[0023] In this invention, unless otherwise specified, all raw materials used in the preparation are commercially available products well known to those skilled in the art.

[0024] In this invention, an electron donor, an electron acceptor, and a solvent are mixed, and the solvent is removed from the resulting mixture to obtain a disk-shaped liquid crystal charge transfer complex precursor.

[0025] In this invention, the molar ratio of the electron donor to the electron acceptor is preferably (1~4):1, more preferably 1:1, 2:1, 3:1 or 4:1. In an embodiment of this invention, the molar ratio of the electron donor to the electron acceptor can be 1:1.

[0026] In this invention, the 2-methyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene has a strong electron-donating ability. Benzophenanthrene, as an extended polycyclic aromatic π-conjugated system, has a certain electron delocalization ability and a high HOMO energy level, exhibiting an electron-donating tendency. The strong resonance electron-donating effect of the five pentoxy groups significantly increases the electron density of the overall π system, thus exhibiting a strong electron donor overall. The 2,4,7-trinitro-9-fluorenone has strong electron-attracting properties. The three strong electron-withdrawing nitro groups (–NO2) significantly reduce the electron density of its π system and significantly decrease the LUMO energy level, thus exhibiting a strong electron-attracting property. The advantage of using both in synergy is that, compared to general donor-acceptor systems, 2-methyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene, due to its high HOMO and highly delocalized π system resulting from polyalkoxy substitution, has a significantly stronger electron-donating ability than common simple aromatic donors (such as monoalkoxybenzenes or carbazole derivatives). Meanwhile, 2,4,7-trinitro-9-fluorenone, thanks to the superposition effect of its three nitro groups, has a significantly lower LUMO than most conventional acceptors (such as ketones or mononitro aromatics), thus forming a larger HOMO–LUMO energy level difference. This results in more prominent energy level matching and structural synergy, driving more efficient charge transfer. At the same time, the π–π interaction between the rigid planar structure of benzophenanthrene and the fluorenone skeleton makes it easier to form an ordered alternating stack. Compared to loosely structured or twisted D–A systems, this complex usually has advantages in charge separation stability, carrier migration path continuity, and spectral response range extension, making it exhibit higher efficiency and tunability in photoelectric conversion and organic electronic materials.

[0027] In this invention, the solvent preferably includes one or more of dichloromethane, ethanol, methanol, and ethyl acetate. When the solvent is two or more of the above-mentioned specific selections, this invention does not impose any special limitation on the ratio of the above-mentioned specific substances, and they can be mixed in any ratio. In an embodiment of this invention, the solvent can be dichloromethane.

[0028] In this invention, the mass ratio of the solvent to the total mass of the electron donor and electron acceptor is preferably (5-10):1, more preferably 5:1, 6:1, 7:1, 8:1, 9:1, or 10:1. In an embodiment of this invention, the mass ratio of the solvent to the total mass of the electron donor and electron acceptor can be 8:1.

[0029] In this invention, the mixing is preferably carried out under stirring conditions. This invention does not impose any special limitations on the stirring process, and any process well known to those skilled in the art can be used.

[0030] In this invention, the solvent removal method from the obtained mixture is preferably heating, and the heating temperature is preferably higher than the boiling point of the organic solvent; the heating time is preferably ≥24 hours; the heating time is sufficient to ensure that the solvent evaporates completely. In an embodiment of this invention, the heating temperature can be 70°C.

[0031] After obtaining the disk-shaped liquid crystal charge transfer composite precursor, the present invention sequentially performs melting treatment, cooling, annealing and quenching on the disk-shaped liquid crystal charge transfer composite precursor to obtain the disk-shaped liquid crystal charge transfer composite.

[0032] In this invention, the melting temperature is preferably 10°C higher than the clearing point of the disk-shaped liquid crystal charge transfer composite precursor, more preferably 10°C higher than the clearing point of the disk-shaped liquid crystal charge transfer composite precursor; the holding time of the melting treatment is preferably 30-60 min, more preferably 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, or 60 min. In an embodiment of this invention, the melting temperature can be 110°C and the time can be 30 min.

[0033] In this invention, the purpose of the melt treatment is to completely melt the mixture of electron donor and electron acceptor into an isotropic state, eliminating the original crystalline or phase-separated structure at the molecular scale, achieving uniform molecular-level mixing and random orientation, thereby breaking the energy level and orientation limitations caused by localized ordered stacking. Donor and acceptor molecules can fully contact and rearrange themselves, significantly improving the interfacial contact probability and charge transfer coupling efficiency. Subsequently, during cooling or further processing, it is easier to form a uniform and controllable D-A microstructure, suppressing macroscopic phase separation and improving overall structural consistency.

[0034] In this invention, the cooling rate is preferably 2~10℃ / min, more preferably 2℃ / min, 3℃ / min, 4℃ / min, 5℃ / min, 6℃ / min, 7℃ / min, 8℃ / min, 9℃ / min, or 10℃ / min; the target temperature for cooling is 30~45℃, preferably 30℃, 35℃, 40℃, or 45℃. In embodiments of this invention, the cooling rate can be 2℃ / min or 10℃ / min, and the target temperature for cooling can be 45℃ or 35℃.

[0035] In this invention, the cooling rate within the above-mentioned range serves to control the dynamic process of the system's transformation from an isotropic molten state to an ordered structure, thereby achieving a balance between crystallization and phase separation of donor-acceptor molecules. Controlled cooling facilitates sufficient molecular diffusion and rearrangement, promotes the formation of ordered π-π stacking and a stable charge-transfer composite structure, and inhibits excessive crystallization and macroscopic phase separation, while preserving a relatively uniform microscopic mixed morphology.

[0036] In this invention, the annealing temperature is preferably 30~45℃, more preferably 30℃, 35℃, 40℃ or 45℃; the holding time is preferably 24~36h, more preferably 24h, 28h, 32h or 36h. In an embodiment of this invention, the annealing temperature can be 45℃ or 35℃, and the holding time can be 24h.

[0037] In this invention, controlling the annealing conditions within the aforementioned range provides the donor-acceptor molecules with adequate thermal energy for slow and sufficient secondary rearrangement and structural relaxation without damaging the existing microstructure. This activates local molecular motion, repairs defects and disordered regions generated during rapid cooling, and avoids excessive crystallization or macroscopic phase separation caused by high temperatures. The longer holding time ensures that this rearrangement process reaches a quasi-equilibrium state, making the D-A interface clearer and more stable, and the π-π stacking more regular, thereby forming a continuous charge transport channel with low trap density.

[0038] In this invention, the target temperature for quenching and shaping is preferably room temperature (20°C). The quenching and shaping method is preferably achieved by setting the temperature on a hot plate.

[0039] In this invention, the function of quenching and shaping is to fix the microstructure and phase state formed in the system during high temperature or annealing by rapidly cooling down, thereby inhibiting further diffusion, rearrangement or phase separation of molecules, and thus stabilizing the established donor-acceptor interface and charge transfer structure.

[0040] The present invention also provides a disk-shaped liquid crystal charge transfer complex prepared by the preparation method described above, wherein the disk-shaped liquid crystal charge transfer complex has a three-dimensional interpenetrating, continuous and isotropic periodic network structure of a dual continuous Gyroid phase.

[0041] In this invention, the disk-shaped liquid crystal charge transfer composite has a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a bicontinuous Gyroid phase. In this invention, the characteristic diffraction peaks of the XRD diffraction pattern of the disk-shaped liquid crystal charge transfer composite are preferably (211), (220), and (321); the ratio between the interplanar spacings (d-values) of (211), (220), and (321) is preferably... The wide-angle region of the disk-shaped liquid crystal charge transfer complex also preferably contains diffraction peaks (d≈3.42~3.46Å) of intermolecular π-π stacking.

[0042] In this invention, the structural formula of the disk-shaped liquid crystal charge transfer composite is: .

[0043] The present invention also provides the application of the disk-shaped liquid crystal charge transfer composite described in the above technical solution or the disk-shaped liquid crystal charge transfer composite prepared by the preparation method described in the above technical solution in optoelectronic devices, wherein the disk-shaped liquid crystal charge transfer composite serves as a carrier transport functional material in optoelectronic devices.

[0044] In this invention, the optoelectronic device preferably includes an organic solar cell or an organic field-effect transistor.

[0045] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0046] XRD parameters in the examples: Formula for calculating the interplanar spacing of the double Gyroid phase (DG): Where: d hkl α is the interplanar spacing between corresponding crystal planes (h, k, l); α is the unit cell constant (lattice constant of cubic crystals); h, k, and l are Miller indices. The XRD diffraction mode of the DG phase shows common diffraction peaks at the following positions: (211) Crystal plane: d200 = a / (220) Crystal plane: d220 = a / (321) Crystal plane: d321=a / ; Example 1 Raw materials for preparation: T5E1 is the electron donor, TNF is the electron acceptor, and dichloromethane is the organic solvent; the molar ratio of T5E1 to TNF is 1:1, and the mass ratio of the dichloromethane to the total mass of T5E1 and TNF is 8:1. Preparation process: T5E1, TNF and dichloromethane were completely dissolved under stirring to obtain a mixed solution; The mixed solution was heated at 70°C for 24 hours to allow the solvent to evaporate completely and dry, thus obtaining the charge transfer complex precursor. The charge transfer composite precursor was subjected to a series of processes, including melt treatment (at 110°C for 30 min, until it was completely melted and entered an isotropic state), cooling (cooling to 45°C at a cooling rate of 2°C / min), annealing (at 45°C for 24 h), and rapid quenching to room temperature (20°C), to obtain a disk-shaped liquid crystal charge transfer composite (with a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a dual continuous Gyroid phase, denoted as CTC1-2). The disk-shaped liquid crystal charge transfer composite was observed using a polarizing microscope (POM), wherein... Figure 1 The polarization texture of the disk-shaped liquid crystal charge transfer composite is shown below. Figure 1 It can be seen that the disk-shaped liquid crystal charge transfer composite exhibits a mosaic pattern texture characteristic of the DG phase; The disk-shaped liquid crystal charge transfer composite was subjected to one-dimensional X-ray diffraction (1D-WAXD) testing, wherein... Figure 2 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite. Figure 2 It can be seen that at 45℃, a sharp diffraction peak d=15.10Å and a series of weaker diffraction peaks d=13.58Å, d=10.17Å, and d=8.64Å appear in the small-angle region, with a ratio of d values ​​of [missing information]. It can be indexed as the (211), (220), and (321) planes of the DG lattice, with lattice parameter a = 37.83 Å. The diffraction peak d = 3.42 Å at 25° in the wide-angle region 2θ corresponds to intermolecular π-π stacking. The carrier mobility of the disk-shaped liquid crystal charge transfer complex was measured using the transit-time method. The test results showed that the hole mobility of the disk-shaped liquid crystal charge transfer complex was 2.85 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 The electron mobility is 0.51 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 .

[0047] Example 2 Raw materials for preparation: T5E1 is the electron donor, TNF is the electron acceptor, and dichloromethane is the organic solvent; the molar ratio of T5E1 to TNF is 1:1, and the mass ratio of the dichloromethane to the total mass of T5E1 and TNF is 8:1. Preparation process: T5E1, TNF and dichloromethane were completely dissolved under stirring to obtain a mixed solution; The mixed solution was heated at 70°C for 24 hours to allow the solvent to evaporate completely and dry, thus obtaining the charge transfer complex precursor. The charge transfer composite precursor was subjected to a series of treatments: melt treatment (at 110°C for 30 min, until it was completely melted and entered an isotropic state), cooling treatment (cooling to 35°C at a cooling rate of 10°C / min), annealing treatment (at 35°C for 24 h), and rapid quenching to room temperature (20°C) to obtain a disk-shaped liquid crystal charge transfer composite (with a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a dual continuous Gyroid phase, denoted as CTC1-10). The disk-shaped liquid crystal charge transfer composite was observed using a polarizing microscope (POM), wherein... Figure 3 The polarization texture of the disk-shaped liquid crystal charge transfer composite is shown below. Figure 3 It can be seen that the disk-shaped liquid crystal charge transfer composite exhibits a mosaic pattern texture characteristic of the DG phase; The disk-shaped liquid crystal charge transfer composite was subjected to one-dimensional X-ray diffraction (1D-WAXD) testing, wherein... Figure 4 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite. Figure 4 It can be seen that at 35℃, a sharp diffraction peak d=15.71Å and a series of weaker diffraction peaks d=13.75Å, d=10.3Å, and d=8.03Å appear in the small-angle region, with a ratio of d values ​​of [missing information]. The peaks of the (211), (220) and (321) planes of the DG lattice can be indexed as DG phase (as long as the peaks of the (211), (220) and (321) planes appear, the orientation of the crystal planes is slightly different each time). The lattice parameter a = 38.64 Å. It can be seen that the diffraction peak d = 3.45 Å at 2θ 25° of the disk-shaped liquid crystal charge transfer complex corresponds to the intermolecular π-π stacking. The carrier mobility of the disk-shaped liquid crystal charge transfer complex was measured using the transit-time method. The test results showed that the hole mobility of the disk-shaped liquid crystal charge transfer complex was 1.74 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 The electron mobility is 0.78 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 .

[0048] Example 3 Referring to Example 2, the difference is that the target temperature for cooling is 32°C, the annealing temperature is 32°C, and a disk-shaped liquid crystal charge transfer composite is obtained. Figure 5 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite. Figure 5 It can be seen that at 32℃, a strong diffraction peak at d=15.76Å and a series of weaker diffraction peaks at d=13.68Å, d=10.34Å, and d=8.02Å appear in the small-angle region of the X-ray diffraction image, with a d-value ratio of [missing value]. The planes (211), (220) and (321) of the DG lattice can be indexed. According to the lattice formula of DG, the lattice parameter a = 38.56 Å is obtained. The diffraction peak in the wide-angle region d = 3.46 Å corresponds to π-π stacking. The carrier mobility of the disk-shaped liquid crystal charge transfer complex was measured using the transit-time method. The test results showed that the hole mobility of the disk-shaped liquid crystal charge transfer complex was 1.83 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 The electron mobility is 0.76 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 .

[0049] Example 4 Referring to Example 2, the difference is that the target temperature for cooling is 30°C, the annealing temperature is 30°C, and a disk-shaped liquid crystal charge transfer composite is obtained. Figure 6 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite. Figure 6 It can be seen that at 30℃, a strong diffraction peak at d=15.77Å and a series of weaker diffraction peaks at d=13.64Å, d=10.33Å, and d=8.02Å appear in the small-angle region of the X-ray diffraction image, with a d-value ratio of [missing value]. The index can be found on the (211), (220), and (321) planes of the DG lattice, with lattice parameter a = 38.50 Å. The diffraction peak in the wide-angle region d = 3.46 Å corresponds to π-π stacking. The carrier mobility of the disk-shaped liquid crystal charge transfer complex was measured using the transit-time method. The test results showed that the hole mobility of the disk-shaped liquid crystal charge transfer complex was 1.79 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 The electron mobility is 0.75 × 10⁻⁶. -4 cm 2 ·V -1 ·s -1 .

[0050] Comparative Example 1 Referring to Example 2, the difference is that the target temperature for cooling is 55°C and the annealing temperature is 55°C, resulting in a disk-shaped liquid crystal charge transfer composite (with a nematic liquid crystal structure). Figure 7 The polarization texture of the disk-shaped liquid crystal charge transfer composite is shown below. Figure 7 It can be seen that the disk-shaped liquid crystal charge transfer composite exhibits curved, continuous brush-like dark cross stripes, showing a typical structure with ordered nematic phase orientation but no layered periodicity. Figure 8 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite. Figure 8 It can be seen that the one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite does not have obvious sharp diffraction characteristic peaks, which belongs to the diffraction characteristics of nematic liquid phase.

[0051] Comparative Example 2 Referring to Example 2, the difference is that the electron donor is 2-ethyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene (T5E2), the target cooling temperature is 35°C, the annealing temperature is 35°C, and a disk-shaped liquid crystal charge transfer complex (CTC2-10) is obtained. The disk-shaped liquid crystal charge transfer composite was observed using a polarizing microscope (POM), wherein... Figure 9 The polarization texture of the disk-shaped liquid crystal charge transfer composite is shown below. Figure 9It can be seen that the disk-shaped liquid crystal charge transfer composite exhibits a large area of ​​dark field and clustered spherical texture, and does not have a DG bicontinuous phase structure; The disk-shaped liquid crystal charge transfer composite was subjected to one-dimensional X-ray diffraction (1D-WAXD) testing, wherein... Figure 10 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite. Figure 10 It can be seen that at 35℃, a strong diffraction peak appears in the small-angle region at d=14.13Å, along with a series of weaker diffraction peaks at d=10.13Å and d=6.50Å, with the ratio of their d values ​​being... It can be indexed as the (110), (200), and (310) planes of the BCC lattice, and there is no bicontinuous phase.

[0052] Comparative Example 3 Referring to Example 2, the difference is that the electron donor is 2-propyl-3,6,7,10,11-pentapentoxybenzophenanthrene (T5E3), the target cooling temperature is 35°C, the annealing temperature is 35°C, and a disk-shaped liquid crystal charge transfer complex (CTC3-10) is obtained. The disk-shaped liquid crystal charge transfer composite was observed using a polarizing microscope (POM). Figure 11 The polarization texture of the disk-shaped liquid crystal charge transfer composite is shown below. Figure 11 It can be seen that the disk-shaped liquid crystal charge transfer composite exhibits a dark field and clustered spherical texture, and does not have a DG bicontinuous phase structure; The disk-shaped liquid crystal charge transfer composite was subjected to one-dimensional X-ray diffraction (1D-WAXD) testing, wherein... Figure 12 The image shows a one-dimensional X-ray diffraction pattern of the disk-shaped liquid crystal charge transfer composite. Figure 12 It can be seen that at 35℃, a strong diffraction peak appears in the small-angle region at d=14.76Å, along with a series of weaker diffraction peaks at d=10.49Å and d=6.54Å, with the ratio of their d values ​​being... It can be indexed as the (110), (200) and (310) planes of the BCC lattice, and there is no bicontinuous phase.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a disc-shaped liquid crystal charge transfer composite, characterized in that, Includes the following steps: After mixing the electron donor, electron acceptor and solvent, the solvent in the resulting mixture is removed to obtain a disk-shaped liquid crystal charge transfer complex precursor. The disk-shaped liquid crystal charge transfer composite precursor was sequentially subjected to melt treatment, cooling, annealing and quenching to obtain the disk-shaped liquid crystal charge transfer composite. The electron donor comprises 2-methyl ester-3,6,7,10,11-pentapentoxybenzophenanthrene; The electron acceptor includes 2,4,7-trinitro-9-fluorenone; The disk-shaped liquid crystal charge transfer complex has a three-dimensional interpenetrating, continuous and isotropic periodic network structure of a dual continuous Gyroid phase. The target temperature for cooling is 30~45℃, and the annealing temperature is 30~45℃.

2. The preparation method according to claim 1, characterized in that, The molar ratio of the electron donor to the electron acceptor is (1~4):

1.

3. The preparation method according to claim 2, characterized in that, The ratio of the mass of the solvent to the total mass of the electron donor and electron acceptor is (5~10):

1.

4. The preparation method according to claim 1, characterized in that, The melting treatment temperature is 10°C higher than the clearing point of the disk-shaped liquid crystal charge transfer composite precursor, and the melting treatment holding time is 30~60 minutes.

5. The preparation method according to claim 1, characterized in that, The cooling rate is 2~10℃ / min.

6. The preparation method according to claim 1, characterized in that, The annealing holding time is 24~36h.

7. The disk-shaped liquid crystal charge transfer composite prepared by the preparation method according to any one of claims 1 to 6, characterized in that, The disk-shaped liquid crystal charge transfer complex has a three-dimensional interpenetrating, continuous, and isotropic periodic network structure of a dual continuous Gyroid phase.

8. The disk-shaped liquid crystal charge transfer composite according to claim 7, characterized in that, The characteristic diffraction peaks of the XRD diffraction pattern of the disk-shaped liquid crystal charge transfer composite are (211), (220) and (321).

9. The application of the disk-shaped liquid crystal charge transfer composite of claim 7 or 8 in optoelectronic devices, characterized in that, The disk-shaped liquid crystal charge transfer composite is used as a carrier transport functional material in optoelectronic devices.

10. The application as described in claim 9, characterized in that, The optoelectronic device includes an organic solar cell or an organic field-effect transistor.

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