ORGANIC SINGLE CRYSTAL COMPOSITE ORIENTED POLYMER FILM, ITS PRODUCTION METHOD, PHOTOELECTRIC DEVICE AND USE THEREOF

Abstract

The present invention provides an organic single crystal composite oriented polymer film, comprising an oriented polymer, which is a polymer fiber in which an organic polymer is aligned in one direction, and an organic single crystal tightly wrapping the polymer fiber, a method for producing the same, a photoelectric device, and its use. The present invention further provides a method for producing the composite film, which includes producing an oriented polymer film by a spatial confinement and oriented crystallization method, and growing an organic single crystal on the oriented polymer film by a solution method. The composite film produced using the method according to the present invention combines the larger heterojunction interface area and long-range order of a bulk heterojunction, achieving high carrier mobility and long exciton diffusion length while ensuring efficient dissociation of excitons. Compared with the organic single crystal composite disordered polymer, the polymer orientation further improves the long-range order of the system, resulting in a 27% decrease in fluorescence lifetime.

Description

[Technical field]

[0001] The present invention relates to the technical field of organic semiconductors, in particular to an organic single-crystal composite oriented polymer film, its preparation method, photoelectric device and its use. [Background technology]

[0002] An organic semiconductor bulk heterojunction is a composite structure formed by the contact of two or more organic semiconductor materials. Organic semiconductor bulk heterojunctions not only combine the electrical and optical properties of different organic semiconductors, but also realize properties that are not available in single-component organic semiconductors. For example, the built-in electric field formed at the heterointerface can greatly improve the dissociation efficiency of photogenerated excitons, making the performance of photovoltaic devices (e.g., solar cells, photodetectors, etc.) based on the heterojunction much higher than that of single-component organic semiconductor photovoltaic devices. However, the performance of photovoltaic devices is poor, for example, in a planar heterojunction consisting of copper(II)phthalocyanine (CuPc) and a cis-trans mixture of the tetracarboxyperylene derivative benzimidazole perylene (PTCBI), because the exciton diffusion length of CuPc is only 10-50 nm, excitons that cannot diffuse to the heterojunction interface recombine, resulting in a short-circuit current that is about half that of bulk heterojunction devices (F.Yang, M.Shtein, SRForrest, Nature Materials, 4, 37(2005)). Furthermore, dissociated carriers may be trapped by defects in the system, leading to a decrease in device efficiency (H.Li, C.Fan, and W.Fu, Angewandte Chemie International Edition, 54, 956(2015)). Therefore, an ideal high performance optoelectronic device requires a large heterojunction contact area, as well as sufficiently fast carrier transport and long exciton diffusion length.

[0003] In order to achieve a large heterojunction contact area, organic photovoltaic devices often adopt a bulk heterojunction structure. In the bulk heterojunction, hole and electron transport materials (i.e., donors and acceptors) are mixed throughout the entire region, and the interface between the two spreads throughout the entire region. When the hole and electron transport materials are in close contact with each other, a depletion layer is formed and a built-in electric field is generated, so that the photogenerated excitons in the organic semiconductor need to be dissociated into free charges under the action of the built-in electric field. Therefore, the bulk heterojunction can increase the number of photogenerated excitons that reach the interface and dissociate within a limited diffusion distance, and further improve the photoelectric performance of the entire device, such as short circuit current and photoresponsivity.

[0004] Currently, the most commonly used methods for fabricating organic semiconductor bulk heterojunctions include the blend solution spin-coating method and the vapor-phase co-deposition method, which randomly separate the phases to form a bulk heterojunction morphology in which two phases coexist. However, random phase separation often generates structures that are unfavorable to carrier migration, such as an isolated island structure in which one phase is completely surrounded by another phase, which is unfavorable to carrier capture by the electrode. Moreover, the structures obtained by these two methods are often amorphous or polycrystalline and have many structural defects. Structural defects can form traps that capture carriers and excitons, or scatter carriers and excitons, hindering their migration, reducing the number of charges collected by the electrode, and reducing the photovoltaic conversion efficiency and other properties.

[0005] To achieve high carrier mobility and long exciton diffusion distance, organic photovoltaic devices need to adopt a long-range ordered structure. The most ideal long-range ordered structure is a structure in which the lattice is periodically arranged and there are no grain boundaries, that is, a single crystal. Single crystals have fewer structural defects and are more favorable for exciton diffusion and carrier migration than amorphous materials or polycrystalline materials, and further reduce the number of excitons migrating to the interface and the number of carriers collected at the electrode, which is expressed as an improvement in the performance of photovoltaic devices, such as carrier mobility. At present, there are several methods for producing small molecule organic semiconductor single crystals, including the poor solvent diffusion method, the solvent volatilization method, and the temperature drop precipitation method. However, the crystals obtained by these methods are often thick and bulky, and the carriers do not have time to move to the electrodes during their lifetime, and the recombination phenomenon of photogenerated carriers is serious, which limits the performance improvement of related optoelectronic devices. Meniscus coating method, printing method, etc. (G.Giri, E.Verploegen, and SCBMannsfeld, Nature, 480, 504(2011); H.Minemawari, T.Yamada, and H.Matsui, Nature, 475, 364(2011)) can grow film-like single crystals on a substrate. However, in order to increase the heterojunction interface area, it is necessary to grow crystals on an uneven substrate surface, and unevenness that exceeds the thickness of the crystal inhibits the progress of crystallization, and a rough surface increases the number of nucleation sites, and in some cases only polycrystals can be obtained (W. Shao, H. Dong and W. Hu, Chemical Science, 2, 590 (2011)).

[0006] On the other hand, for polymer organic semiconductors, the crystallization process involves multiple chain structural transitions, so there are multiple potential barriers, and even obtaining single crystals is difficult (JA Lim, F. Liu, and S. Ferdous, Materials Today, 13,14(2010)). At present, attempts to construct long-range ordered organic polymer semiconductors focus on the formation of oriented structures, including solution shearing and mechanical friction methods. However, in the solution shearing method, the polymer forms nuclei at the air-liquid interface, and the obtained polymer film is obviously oriented only on the surface, and the side close to the base is almost isotropic (D. Wu, M. Kaplan, and HW Ro, Chemistry of Materials. 30, 1924(2018)). The mechanical friction method has high operational requirements, not only because it requires repeated friction by a specific design device, but also because it requires the orientation of the organic polymer semiconductor to be induced by using highly oriented polytetrafluoroethylene (PTFE) as a substrate (L.Biniek, S.Pouget, and D.Djurado, Macromolecules, 47, 3871 (2014)). Moreover, after the polymer is oriented, oriented undulations are formed on the polymer surface, and the surface roughness is also increased, which results in uneven shrinkage of the edges of the solution droplet during the subsequent film-like low-molecular single crystal growth. In addition, the high roughness promotes local nucleation, which is unfavorable to the formation of single crystals and the compound growth of single crystal arrays.

[0007] As mentioned above, currently, organic semiconductor photoelectric devices can only consider one of the large heterojunction contact area and long-range order, and it is difficult to achieve both at the same time. Due to the self-limiting nature of single crystals, single crystals tend to form regular convex polyhedral shapes to minimize the system energy, and cannot easily sink into another phase to form an undulating surface, so it is somewhat difficult to realize a structure that combines the large interface area and long-range order of bulk heterojunctions. One feasible method is to orient two organic semiconductor polymers together in a blend solution to form a bulk heterojunction, but oriented polymer semiconductors have grain boundaries and their long-range order is not as good as that of single crystals. On the other hand, small molecule single crystal films are usually composed of band-like crystals with a micron-scale width, so the heterojunction formed by two types of small molecule single crystals is a planar heterojunction, which has a limited interface area and photogenerated excitons cannot diffuse to the interface and dissociate sufficiently. Therefore, a composite structure of a low molecular weight single crystal and an oriented polymer is expected to maximize the long-range order of the system while at the same time forming a large heterojunction contact area and achieving excellent photoelectric performance.

[0008] There are currently several attempts to construct long-range ordered bulk heterojunctions of organic small molecule single crystals and polymer semiconductors. In the literature (J. Ren, S. Meng, and X. Guo, Journal of the American Chemical Society, 142, 1630 (2020)), inspired by the fact that crystals can be embedded in organic gel fibers in the mineralization phenomenon of living organisms, C in poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) gel was synthesized. 60 MEH-PPV gel fibers were uniformly embedded inside the crystal obtained by growing C 60The crystals still retain their long-range order. However, the guest embedding content of the long-range ordered bulk heterojunctions constructed by this method is limited, mostly less than 1 wt%, and the resulting C 60 The crystal has a three-dimensional hexagonal bipyramid shape of about 100 μm, and when constructing a device, electrodes can only be randomly deposited at certain positions on the crystal through a mask plate, which is highly uncontrollable and inconvenient to operate. In the literature (H. Li, G. Xue, and J. Wu, Chinese Chemical Letters, 28, 2121 (2017)), fibers of perylene bisimide (PBI) derivatives are dispersed on a base in advance, and then a single crystal array of 6,13-bis(triisopropylsilylethynyl)-pentacene (Tips-pentacene) is grown on it by droplet-pinned crystallization (DPC), and the single crystal grows according to the undulations of the fibers, forming a large contact area and forming a long-range ordered bulk heterojunction. However, since the PBI fibers are randomly dispersed on the base by the spin coating method, the surface undulations are relatively small and uniform, and the effect on the subsequent growth of Tips-pentacene crystals is not significant. In addition, the fibers produced in this way have no obvious orientation, and the crystallinity of the PBI fibers used in the literature is poor, and the long-term order of the system can be further improved by selecting and orienting the crystalline polymer semiconductor.

[0009] In view of the above, the prior art has been unable to produce long-range ordered bulk heterojunction films as described above, and there are mainly four problems: 1) The polymer crystallization process is complicated and involves the conversion of multiple chain conformations, so it is difficult to achieve better orientation with existing methods for producing oriented polymer organic semiconductors. 2) Oriented polymer organic semiconductors are formed by the assembly of fibers of different thicknesses and thicknesses, and have a rough surface. Unevenness that exceeds the thickness of the crystal hinders the growth of single crystals, while the rough surface increases the number of nucleation sites, making it easier for the crystal to become polycrystalline. 3) Due to the self-limiting nature of single crystals, single crystals tend to form regular convex polyhedral topographies to minimize the system energy, and cannot easily form undulating surfaces that embed polymer fibers. 4) The selection of growth systems and solvents has the necessary restrictions to ensure that the solvent used to grow single crystals in the subsequent solution method does not dissolve the oriented fibers pre-dispersed on the base. Therefore, how to obtain an ideal long-range ordered bulk heterojunction film consisting of ideal small-molecule organic semiconductor single crystals and oriented polymer organic semiconductors is a major technical challenge and a major obstacle to the realization of high-performance organic optoelectronic devices. Summary of the Invention [Problem to be solved by the invention]

[0010] In response to the shortcomings of the prior art, the present invention provides an organic single crystal composite oriented polymer film, a manufacturing method thereof, a photoelectric device and its use, which can form a heterojunction that realizes high carrier mobility and long exciton diffusion length while ensuring efficient exciton dissociation and long-range order at the same time, while achieving a larger heterojunction interface area than that of a bulk heterojunction. According to the composite film manufactured by the method of the present invention, the fluorescence lifetime of the long-range ordered bulk heterojunction of the present invention is reduced by 81% compared with the short-range ordered bulk heterojunction obtained by spin coating. Compared with the bulk heterojunction of the organic single crystal composite disordered polymer semiconductor, the present invention improves the long-range order of the system by orienting the polymer, and reduces the fluorescence lifetime by 27%, thereby revealing that the organic single crystal composite oriented polymer semiconductor film structure has the potential to improve the performance of photoelectric devices. [Means for solving the problem]

[0011] In order to achieve the above objectives, the technical solutions of the present invention are as follows:

[0012] A composite oriented polymer film containing an oriented polymer, which is a polymer fiber in which an organic polymer is aligned and grown in one direction, and an organic single crystal, in which the polymer fibers are different in length and aligned in the same direction, and the organic polymer molecular chains also have a certain crystal assembly alignment. The principle of the growth of the polymer fiber is that the organic molecular chains form a fiber shape by crystallization, and then the fibers are aligned and grown in the same direction, but the direction in which the fibers are aligned and grown may be the same or different from the molecular chain direction. The organic single crystals tightly wrap around the polymer fiber. Furthermore, the tight wrapping means that the organic semiconductor single crystals grow in close contact with the surface of the polymer fiber.

[0013] Furthermore, the tight wrapping is detected by observing whether the surface microtopography of the organic single crystal is undulating and whether there is a depression at the bonding surface between the organic single crystal and the oriented polymer, where the sample height is lower than the edge position in a narrow range (usually 100 nm or less) where the edge sample heights on both sides are almost the same.

[0014] Furthermore, the tight wrapping is detected by measuring the depth of the depression on the bonding surface between the organic single crystal and the oriented polymer, the depth of the depression being the difference in height between the lowest point of the depression and the edge position of the depression, and when the polymer fiber is not embedded in the organic single crystal, the bottom surface of the organic single crystal is flat or there is only a growth step, and there is no depression, i.e., the depth of the depression is 0 nm. Therefore, 10 depressions on the bonding surface between the organic single crystal and the oriented polymer may be randomly selected and the average depth of the depressions may be measured.

[0015] Furthermore, when the recess depth is 5 nm or more, it is believed that the organic single crystal grows in firm adhesion to the oriented polymer.

[0016] Here, a sample of the bonding surface between the organic single crystal and the oriented polymer may be produced by spin-coating an aqueous polyvinyl alcohol solution on the upper surface of the organic single crystal composite oriented polymer film at a rotation speed of 2000 rpm for 30 seconds, and then peeling off the polyvinyl alcohol after drying to expose the bonding surface.

[0017] The organic single crystal is a single crystal in which an organic semiconductor is grown on a polymer fiber, and the organic semiconductor in the present invention is an organic semiconductor molecule whose molecular formula, molecular structure, and molecular weight are clearly fixed, and preferably, the organic semiconductor is one or more selected from linear benzo compounds and derivatives thereof, linear heterobenzo compounds and derivatives thereof, benzothiophene compounds and derivatives thereof, perylene and derivatives thereof, and fullerene and derivatives thereof.

[0018] Further, the organic semiconductor may be 6,13-bis(triisopropylsilylethynyl)pentacene (Tips-pentacene), 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene (Tips-TAP), 2,7-dioctyl[1]benzothieno[3,2-b][1]-benzothiophene (C8-BTBT), or fullerene (C 60 ), or perylene. The derivative is formed by replacing a part of an atom or atomic group in a molecule of a compound with another atom or atomic group, for example, Tips-pentacene is a derivative of pentacene.

[0019] The organic polymer grown as an oriented polymer in the present invention is an organic semiconductor molecule having a molecular weight distribution in which a series of monomer units are linked, and is preferably a polymer formed by polymerizing a linear conjugated homopolymer, a donor-acceptor alternating copolymer, or a low molecular weight organic semiconductor. The low molecular weight organic semiconductor generally refers to a low molecular weight having a molecular weight of less than 1000 and a clear molecular weight and structural formula, such as 2,2'-((2Z,2'Z)-((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b']dithiophene). -2,7-diyl)bis(methanylylidene))bis(3-oxo-2,3-dihydro-1H-indene-2,1-dylidene))dimalononitrile (2,2'-((2Z,2'Z)-((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis(methanylylidene))bis(3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile, IDIC), (2,2'-((2Z,2'Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro[1,2,5]thiadiazolo[3, 4e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylidene))bis(3-oxo-2,3-dihydro1H-indene-2,1-dylidene))dimalononitrile) ((2,2'-((2Z,2'Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro[1,2,5]thiadiazolo[3,4e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g ]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(3-oxo-2,3-dihydro1H-indene-2,1-diylidene))dimalononitrile), Y5), 2,2'-((2Z,2'Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-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-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-dylidene) )dimalononitrile(2,2'-((2Z,2'Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-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-2,10-diyl)bis(methanylyliden e))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile, Y6) and the like are linked directly or via a conjugated linking unit such as a carbon-carbon double bond or a thiophene ring. Examples of polymers formed from low-molecular-weight organic semiconductors include PZ1 (poly[(2,2'-((2Z,2'Z)-((4,4,9,9-tetrahexadecyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b ']dithiophene-2,7-diyl)bis-(methanylylidene))bis(3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile-alt-2,5-thiophene)], poly[(2,2'-((2Z,2'Z)-((4,4,9,9-tetrahexadecyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis-(methanylylidene))bis(3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile-alt-2,5-thiophene)]), PY-IT(poly[(2,2'-((2Z,2'Z)-((12,13-Bis(2-octyldodecyl)-3,9-diundecyl-12,13-dihydro[1,2,5]thiadiazolo[ 3,4e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4, 5]thieno[3,2-b]-indole-2,10-diyl)bis(methanylidene))bis(3-oxo-2,3-dihydro-1H-indene-2,1-dylidene))dimalononitrile-alt -2,5-thiophene)], poly[(2,2'-((2Z,2'Z)-((12,13-bis(2-octyldodecyl)-3,9-diundecyl-12,13-dihydro[1,2,5]thiadiazolo[3,4e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]-indole-2,10-diyl)bis(methanylylidene))bis(3-oxo-2,3-dihydro-1H-indene-2,1-diylidene)) dimalononitrile-alt-2,5-thiophene)]), and the like.

[0020] Preferably, the organic polymer is poly[(2,6-(4,8-bis(5-(2-ethylhexyl-3-fluoro)thiophen-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c ']dithiophene-4,8-dione)](Poly[(2,6-(4,8-bis(5-(2-ethylhexyl-3-fluoro)thiophene-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione)], PM6), PY-IT, etc.

[0021] Preferably, the organic single crystal composite oriented polymer film further comprises a substrate on which the blended polymer is grown and aligned in one direction.

[0022] The substrate may be a glass plate, a silicon wafer, a metal oxide (AlO X The substrate may be a rigid substrate such as ITO, FTO, etc., or a flexible substrate such as polyimide (PI), polyethylene terephthalate (PET), mica sheet, etc., which is not dissolved or corroded by the solvents used in the manufacturing process.

[0023] To facilitate the subsequent growth of organic single crystals, the substrate may be modified, and preferably the substrate is modified with silane group-containing self-assembly molecules, phosphate group-containing self-assembly molecules, or thiol group-containing self-assembly molecules.

[0024] Preferably, the substrate is a cross-linked poly(methylmethacrylate) (c-PMMA) or a benzocyclobutene (divinyltetramethyldisiloxane-bis(benzocyclobutene) (BCB) modified substrate.

[0025] The present invention further provides a simple method for producing an oriented polymer film, by using a room temperature solid organic solvent oriented crystallization process to place a polymer solute within the spatial confines of a thin layer for restricted crystallization, and one-dimensionally orient the polymer on a substrate by the flow field during the solidification process. The substrate here may be a substrate in the narrow sense, and may be a glass plate, a silicon wafer, a metal oxide (AlO XThe substrate may be a hard substrate such as PTFE (Indium Tin Oxide, Indium Tin Oxide, FTO) or a flexible substrate such as polyimide (PI), polyethylene terephthalate (PET), or mica sheet. The substrate may be modified with a silane group-containing self-organizing molecule, a phosphate group-containing self-organizing molecule, or a thiol group-containing self-organizing molecule. The substrate may also be a substrate in the broad sense, that is, when applied to a semiconductor device, the substrate has an electrode and a transport layer, and polymer fibers can be oriented and grown on the transport layer. The oriented polymer film produced by the present invention has good orientation over the entire thickness range compared to the solution shear method and the mechanical friction method, does not require multiple operations using a specific mold, and can be widely applied to a variety of substrates.

[0026] When preparing an oriented polymer film by the spatial restriction and oriented crystallization method, an integrated device including a motor, a screw rod, a ball nut, a jig and a temperature gradient hot stage is adopted, the output shaft of the motor is connected to the screw rod, the screw rod is screwed into the ball nut, the jig is used to clamp the substrate, the temperature gradient hot stage is arranged parallel to the screw rod, the jig is fixedly connected to the ball nut, and the jig is placed on the temperature gradient hot stage. The motor rotates the screw rod, and the ball nut moves on the screw rod to move the jig from the high temperature region to the low temperature region on the temperature gradient hot stage, that is, to move the substrate from the high temperature region to the low temperature region, so that the moving speed of the jig is equal to the moving speed of the substrate, which is equal to the solidification speed of the organic polymer in the organic polymer solution. The temperature gradient hot stage may be a Kofler melting point meter, and the substrate is placed on the temperature gradient hot stage, and the size of the substrate is preferably not larger than the size of the hot stage, but is preferably a square with a side length of 1 to 1.5 cm.

[0027] Specifically, the operation is as follows: A desired mass of organic polymer and an organic solvent that is solid at room temperature are weighed, and the organic solvent is melted by heating at a temperature between the melting point and boiling point of the organic solvent to obtain an organic polymer solution. Next, a substrate is placed on a temperature gradient hot stage equipped with a jig, the organic polymer solution is sucked and dropped onto the substrate, and another clean glass plate (other covers are also possible, and a transparent glass plate that makes it easy to observe the solidification state of the solvent) that has been preheated on a hot stage at a temperature higher than the melting point of the organic solvent is quickly placed on the solution droplet, and preferably, the surface of the glass plate that comes into contact with the organic polymer solution is modified with octadecyltrichlorosilane (OTS), and the glass plate is modified for the purpose of being easily removed after the solvent and organic polymer are solidified, without adhering the oriented polymer, so as to leave a complete film on the substrate. Here, the temperature of the initial placement position of the substrate is equal to or higher than the melting point of the organic solvent used. Then, an article pre-cooled at a low temperature (e.g., tweezers head, needle head, etc.) is brought into contact with the low-temperature surface of the hot stage of the glass plate covered on the substrate, forming a gradient in which the temperature decreases vertically from the substrate to the glass plate covered thereon, and the organic solvent in the liquid film is nucleated and grown on the surface of the upper glass plate under low-temperature induction. Preferably, when the nucleation of the solvent is observed, the pre-cooled article for inducing nucleation is removed. Preferably, the glass plate is pressed with a weight of m≧100g, thereby making it possible to reduce the film thickness of the liquid film sandwiched between the glass plate and the substrate, thereby making it possible to reduce the film thickness and roughness of the resulting polymer film, as well as to enhance the spatial restriction effect and facilitate the formation of an oriented structure and the subsequent growth of organic single crystals.

[0028] Then, the motor is started, the screw rod is rotated to move the ball nut, and the jig is moved with the substrate toward the low temperature region of the temperature gradient hot stage at a constant speed. During the growth of the organic solvent crystals, the organic polymer solute is constantly extruded and concentrated in a very thin range near the substrate surface, and at the same time, the orientation movement in the temperature gradient hot stage causes the orientation crystallization of the organic solvent, so that the polymer exhibits a concentration decrease gradient from the low temperature region to the high temperature region of the temperature gradient hot stage. Therefore, due to the cooperation of the space limiting effect and the concentration gradient, the organic polymer gradually undergoes orientation crystallization from the high temperature to the low temperature region along with the orientation crystallization of the organic solvent, and when the liquid film is completely solidified, a polymer semiconductor film oriented in one direction is finally obtained. Preferably, the moving speed of the jig controlled by the motor is 5 to 800 μm / s, that is, the moving speed of the substrate is 5 to 800 μm / s.

[0029] The glass plate is then peeled off, and the solidified liquid film is left in an environment below the melting point of the organic solvent or in a vacuum to sublimate the organic solvent, or the solid organic solvent is removed with an orthogonal solvent, which is a solvent that dissolves the solid organic solvent but does not dissolve the produced organic polymer, to obtain an oriented polymer film on the substrate.

[0030] The low-temperature pre-cooling is a relative concept, and generally, if the temperature is lower than the melting point of the organic solvent and the difference between the melting point of the organic solvent and the temperature is 80° C. or more, the article is considered to have been pre-cooled at a low temperature.

[0031] When modifying a glass plate with OTS, specifically, in a glove box with a nitrogen atmosphere, 8 μL of OTS is aspirated using a pipette gun and injected into a sample bottle containing 20 mL of meta-xylene, and the OTS is completely transferred by several aspirates. The sample bottle is capped, shaken well, and removed from the glove box. The glass plate is washed with an alkaline solution, and then plasma-treated at 10% power for 120 s. The treated glass plate is placed in a PTFE petri dish, the prepared OTS solution is poured in, the lid is put on, and the plate is left to react in an air environment for 1 to 2 hours. After the reaction is completed, the glass plate modified with OTS is obtained by ultrasonic cleaning using chloroform.

[0032] Here, the organic polymer is an organic semiconductor molecule having a molecular weight distribution in which a series of monomer units are linked, and preferably, it is a linear conjugated homopolymer, a donor-acceptor alternating copolymer, or a polymer formed by polymerizing a low-molecular organic semiconductor.

[0033] Preferably, the organic polymer is poly(3-hexylthiophene-2,5-diyl) (P3HT), PM6, PY-IT, etc.

[0034] Based on the same inventive concept, the present invention further provides a method for manufacturing the above-mentioned organic single-crystal composite-oriented polymer film, which includes the following steps. S1: An oriented polymer film is manufactured on a substrate by the above-mentioned space restriction and oriented crystallization method, and the concentration of the organic polymer solution therein is set to c. In order to ensure that the roughness of the oriented polymer fibers pre-dispersed at the bottom is not too large and such fibers do not protrude too high to prevent single-crystal growth, except for pressing the liquid film thinly using the above-mentioned weights, the concentration of the polymer solution is preferably 0 < c ≤ 5 mg / mL, and more preferably 2 ≤ c ≤ 4 mg / mL. S2: Grow an organic single crystal on the oriented polymer.

[0035] In order to grow an organic single-crystal film on the rough surface, a substrate is reasonably selected and modified to form nuclei at the gas-liquid interface, enabling the crystal to grow over the bottom obstacles into a continuous single crystal. Furthermore, since the organic single crystal is flexible, the single crystal grown at the gas-liquid interface can partially conform to the undulations of the bottom surface and continuously fill the gap between the single crystal and the fibers on the bottom surface as the solution volatilizes, realizing their close adhesion. Since the polymer fibers on the substrate are arranged in a predetermined direction, the shrinkage of the liquid droplets along the vertical orientation direction is somewhat hindered, so usually a relatively continuous organic single crystal can be obtained in the orientation direction parallel to the polymer in the bottom layer. The substrate is a glass plate, a silicon wafer, a metal oxide (AlO XThe substrate may be a hard substrate such as ITO, FTO, etc., or a flexible substrate such as polyimide (PI), polyethylene terephthalate (PET), mica sheet, etc., which is not dissolved or corroded by the solvent used in the manufacturing process, and may be subsequently modified to better grow single crystals on the oriented polymer. The modification material of the substrate is one or more film materials of silane group-containing self-assembly molecules, phosphate group-containing self-assembly molecules, and thiol group-containing self-assembly molecules. More preferably, modification with BCB and modification with c-PMMA are used.

[0036] Regarding the modification of the substrate with the c-PMMA, specifically, PMMA is dissolved by heating in n-butyl acetate at 90°C to prepare a 25 mg / mL solution, which is then cooled and prepared for use. 1,6-bis(trichlorosilyl)hexane (add 20 μL of crosslinking agent to the solution) is added as a crosslinking agent to the n-butyl acetate solution of PMMA for use. The substrate is placed on a spin coater, the vacuum pump is turned on to adsorb the substrate, the solution is dripped onto the substrate surface so as to completely cover the surface, spin-coated at 4000 rpm for 30 s, and then heat-treated at 100°C for 1 h in a nitrogen atmosphere to crosslink the substrate.

[0037] Regarding the substrate modification with BCB, specifically, the substrate is plasma-treated at 10% power for 120 s and then transferred to a glove box in a nitrogen atmosphere. The BCB precursor stock solution is diluted with trimethylbenzene (volume ratio 1:30), mixed thoroughly, and filtered through a filter membrane with a pore size of 220 nm for preparation for use. The plasma-hydrophilized substrate is placed on a spin coater, and the mesitrylene solution of the BCB precursor is dripped onto the substrate until the substrate surface is completely covered. The substrate is then spin-coated at a rotation speed of 4000 rpm for 30 s, and then heat-treated in a nitrogen atmosphere at 123°C, 185°C, and 247°C in that order for 30 min to crosslink the substrate.

[0038] Furthermore, in step S2, an organic single crystal is grown on the oriented polymer by a solution method.

[0039] Furthermore, the step of growing an organic single crystal by the solution method specifically includes: First, step S201 of dissolving an organic semiconductor in a solvent to prepare an organic semiconductor solution; and step S202 of growing organic single crystals on the oriented polymer by either a droplet immobilization method or its variants or a meniscus coating method.

[0040] Furthermore, the step of producing a single crystal by the droplet fixing crystallization method specifically includes: The method includes step S202 of placing the substrate on which the oriented polymer has been produced into a container, placing the substrate on which the oriented polymer has been produced preferably on a cover glass, then placing the cover glass on a petri dish, placing one drop of a droplet fixing material in the center of the substrate on which the oriented polymer has been produced, preheating the entire container and placing it in this preheated temperature environment, then dropping an organic semiconductor solution onto the droplet fixing material, quickly sealing the container so as not to shake the container when sealing in order to prevent the droplet from shifting position, and obtaining an organic single crystal when evaporation of the solvent in the droplet is completed.

[0041] The specific operation is as follows. In a clean room, the substrate on which the oriented polymer is manufactured is placed on a cover glass, the cover glass is placed on a petri dish, and one drop of the fixed object is placed in the center of the substrate. The whole is placed on a hot stage and preheated for 5 to 10 minutes so that the temperature is equilibrated. In this preheated temperature environment, 15 to 25 μL of a solution in which the organic semiconductor is dissolved is aspirated with a pipette gun and dropped onto the fixed droplet object, and the petri dish is quickly covered. In order to prevent the droplet from shifting position, the petri dish is prevented from shaking when sealed. After 5 to 30 minutes, when the evaporation of the solvent in the droplet is completed, an organic small molecule single crystal is obtained.

[0042] Furthermore, the droplet fixing object is a silicon wafer, a needle, or a metal rod.

[0043] Furthermore, the size of the silicon wafer is 3 x 3 mm 2 It is.

[0044] Furthermore, in a modified form of the droplet fixing crystallization method, the substrate on which the oriented polymer has been produced is placed in a container, the substrate is tilted by 0.1 to 5°, and the entire container is preheated. In this preheated temperature environment, the organic semiconductor solution is dropped onto the droplet fixing object, the container is quickly sealed, and when the evaporation of the solvent in the droplet is completed, an organic single crystal is obtained.

[0045] Furthermore, the step of growing an organic single crystal by the meniscus coating method specifically includes adjusting the distance between the coating tool and the substrate on which the oriented polymer is produced to 100 to 150 μm, preheating the substrate on which the oriented polymer is produced for 10 min, injecting an organic semiconductor solution into the gap between the coating tool and the substrate, and then moving the coating tool at a constant speed parallel to the substrate to shear the organic semiconductor solution. After coating is completed, the excess organic semiconductor solution is sucked up so as not to dissolve the grown crystal by reflow; or The method includes immersing a substrate on which an oriented polymer has been produced into an organic semiconductor solution, lifting the substrate, forming a meniscus between the lifted substrate and the organic semiconductor solution, and completely removing the substrate from the organic semiconductor solution.

[0046] Further, the application tool is a scraper, a blade, a smooth rod, a coil rod, a brush, or a bead.

[0047] Furthermore, the moving speed of the coating tool is 10 to 800 μm / s.

[0048] In step S201, the solvent for dissolving the organic semiconductor is selected in consideration of the volatilization rate at a predetermined temperature, the solubility in the organic semiconductor, and the solubility in the oriented polymer organic semiconductor dispersed on the substrate. Preferably, the solubility of the organic semiconductor in the solvent is greater than 0.2 mg / mL, and the solvent does not dissolve the oriented polymer at the operating temperature.

[0049] Further, the solvent is one or a mixture of more than one of n-hexane, n-heptane, meta-xylene, and 4-methyl-2-pentanone.

[0050] The concentration of the organic semiconductor solution is 0.1 to 0.8 mg / mL, and preferably 0.2 to 0.6 mg / mL. When a different solvent is selected to dissolve the organic semiconductor, the preheating temperature of the substrate is different. For example, in the case of n-hexane, the preheating temperature is 20 to 28 ° C., in the case of n-heptane, the preheating temperature is 36 to 40 ° C., and in the case of meta-xylene and para-xylene, the preheating temperature is 40 to 50 ° C. In the case of n-hexane, the preheating temperature may be 4 to 6 ° C., but thereafter, it is no longer necessary to seal the petri dish with a sealing film. Most preferably, Tips-pentacene is a 0.4 mg / mL n-hexane solution, and the preheating temperature is 25 ° C. Tips-TAP is a 0.3 mg / mL n-hexane solution, and the preheating temperature is 25 ° C.

[0051] The present invention further provides a photoelectric device, comprising the above organic single crystal composite oriented polymer film, or an organic single crystal composite oriented polymer film produced by the above method for producing an organic single crystal composite oriented polymer film.

[0052] Preferably, the optoelectric device is selected from a solar cell, a photodetector, a light emitting diode, or a light emitting field effect transistor.

[0053] Preferably, the photodetectors are photomistor and photosensitive field effect transistors.

[0054] Preferably, the optoelectronic device further comprises an electrode and a transport layer according to the needs of an actual device configuration, and the electrode and transport layer may be prefabricated on a substrate and then a composite film may be fabricated on the transport layer, or a composite film may be directly fabricated on a substrate and the electrode and transport layer may be fabricated on the composite film.

[0055] Preferably, the method of manufacture of the electrodes is either vacuum deposition, sputtering, followed by transfer.

[0056] Preferably, the material of the electrodes is one or a combination of two or more selected from gold, aluminum, silver, and titanium.

[0057] Preferably, the method of manufacture of the transport layer is either spin coating, vacuum deposition, or sputtering followed by transfer.

[0058] Preferably, the material of the transport layer is selected from ZnO, TiO2, MoO3.

[0059] The present invention further provides uses of the above organic single crystal composite oriented polymer film, the organic single crystal composite oriented polymer film produced by the above method, and the above photoelectric device in one or more of the following fields: organic photovoltaic power generation, organic photodetection, organic display, transportation and logistics, mining and metallurgy, environment, medical equipment, explosion-proof detection, food, water treatment, medicine, and biology.

[0060] By adopting the above technical solutions, the present invention has the following advantages and positive effects compared with the prior art:

[0061] The present invention overcomes technical prejudices and realizes the manufacture of a heterojunction composite film of an organic single crystal and an oriented polymer, in which the oriented polymer is composed of organic polymer fibers oriented in one direction, and together with the organic semiconductor single crystal, ensures the long-range order of the entire heterojunction, which is favorable for the high-speed movement of carriers and the long-distance diffusion of excitons. The organic semiconductor single crystal tightly wraps the polymer fibers and embeds the fibers in the organic single crystal, forming a large heterojunction interface area, expanding the distribution range of the built-in electric field, and promoting the dissociation of photo-generated excitons. The present invention combines the advantages of long-range order and bulk heterojunction, and significantly improves the photophysical properties compared with existing fabrication methods. The long-range order of organic semiconductor single crystals and oriented polymer organic semiconductors ensures long-range diffusion of excitons and efficient transfer of carriers, and can fully transfer excitons to the heterojunction interface, and can efficiently capture and collect carriers after dissociation, reducing loss due to defect capture; on the other hand, the large-area adhesion of the bulk heterojunction efficiently dissociates excitons, reduces energy loss due to recombination, and increases the utilization rate of incident light energy. Therefore, the final long-range ordered bulk heterojunction structure exhibits significant fluorescence quenching and the shortest fluorescence lifetime, and is expected to be applied to the design of devices related to high-performance photoelectric conversion.

[0062] In order to produce an oriented polymer film, the present invention confines the solvent crystals in a thin two-dimensional space by the repulsive force of the solvent crystals against the polymer solute in the oriented crystallization, and further realizes one-dimensional orientation by the flow field in the crystallization. In order to firmly adhere the organic single crystals to the oriented polymer fibers, the present invention controls the liquid film thickness, concentration, and solidification rate of the organic polymer solution when producing the oriented polymer, thereby controlling the undulations of the polymer fibers of the oriented polymer and facilitating the growth of the organic single crystals on the polymer fibers. Then, by using appropriate substrate modification, the position that affects the nucleation of the organic semiconductor is controlled, and by using the flexibility of the film-like single crystal to follow the undulations of the underlying polymer fibers, the organic semiconductor solution is completely evaporated by selecting the appropriate concentration of the organic semiconductor solution, the crystal growth temperature, the solvent, and its volatilization rate, and then the organic semiconductor solution is grown as an organic single crystal that is firmly adhered to the underlying oriented polymer fibers.

[0063] Furthermore, since the present invention is produced based on a solution process, the operation is simple, the range of application is wide, the material system is designable, special and complicated equipment is not required, and mass production is also possible. [Brief description of the drawings]

[0064] [Figure 1]These are two cases of organic single crystals grown on oriented polymer fibers. (a) The organic single crystal of the present invention tightly wraps around and embeds the polymer fiber to form a bulk heterojunction. (b) The organic single crystal has a small contact area with the polymer fiber, and is supported only by a few rough points on the fiber, whereas the single crystal itself maintains a flat crystal face. (c) is an AFM height map of the bonding surface between the organic single crystal and the oriented polymer fiber in Example 6, which corresponds to the case of (a). (d) is an SEM image of the contact surface of the C60 single crystal obtained by uniformly forming a nucleus in a droplet using the poor solvent diffusion method with the basal-oriented P3HT fiber, which shows that the surface is almost flat except for a small growth step, which corresponds to the case of (b). [Diagram 2] Three cases are shown in which the long-range order of the samples is determined under cross-polarized light by a polarizing microscope. (a) and (b) are organic single crystals formed in Example 1, which show synchronous light-dark changes and have long-range order. (c) and (d) are non-oriented P3HT fiber films formed in Comparative Example 7, which have no brightness and no long-range order. (e) and (f) are organic polycrystals formed in Comparative Example 1, which always have brightness and no long-range order. [Diagram 3] The purpose of this study is to determine whether the system has long-range order by selected area electron diffraction. (a) In Example 1, two sets of single crystal-like diffraction spots of Tips-pentacene and P3HT are presented, and the system has long-range order. (b) In Example 6, two sets of single crystal-like diffraction spots of Tips-TAP and P3HT are presented, and the system has long-range order. (c) In Comparative Example 8, Tips-pentacene shows multiple sets of diffraction spots, P3HT shows diffraction rings, and the system has short-range order. [Figure 4] FIG. 1 is a plan view of an apparatus used to obtain oriented polymer fibers by spatial confinement and oriented crystallization. [Diagram 5]1 shows optical microscope topographies of composite films obtained in the examples and comparative examples of the present invention, where (a) is Example 1, (b) is Comparative Example 1, (c) is Comparative Example 2, (d) is Comparative Example 3, (e) is Comparative Example 4, (f) is Comparative Example 5, (g) is Comparative Example 6, (h) is Comparative Example 6, and (i) is Comparative Example 8. [Figure 6] The obtained P3HT selected area electron diffraction images are (a) an oriented P3HT film obtained by spatially confined and oriented crystallization method using 1,3,5-trichlorobenzene as a solvent in Example 1, and (b) a disordered P3HT film produced by spin coating in Comparative Example 8. [Figure 7] In Example 1, the crystal plane diffraction intensity of the (100) two-dimensional GIWAXS diagram obtained by irradiating X-rays in the orientation direction of the P3HT obtained by spatial confinement and oriented crystallization is plotted against the direction φ. [Figure 8] 1A and 1B are SEM images of the organic single crystal of Example 1, in which (a) is the bonding surface with the polymer fiber, (b) is the top surface of the organic single crystal, and (c) is the bonding portion between the side surface of the organic single crystal and the polymer fiber. [Figure 9] 10A-10C show the steady-state fluorescence characteristics of photovoltaic devices versus oriented P3HT fibers, (a) for Example 1 and (b) for Example 6. [Figure 10] 1 shows transient fluorescence tests of photovoltaic devices and data fitting thereof, (a) photovoltaic devices based on Example 1, Comparative Example 7 and Comparative Example 8, (b) photovoltaic devices based on Example 6, Comparative Example 9 and Comparative Example 10. [Figure 11] 1 is an optical microscope photograph under crossed polarized light of Example 2. [Figure 12] 1 is an optical microscope photograph under crossed polarized light of Example 3. [Figure 13] 1 is an optical microscope photograph under crossed polarized light of Example 4. [Figure 14] 1 is an optical microscope photograph under crossed polarized light of Example 5. [Figure 15] 1 is an optical microscope photograph of Example 6 under crossed polarized light. [Figure 16] 1 is an optical microscope photograph under crossed polarized light of Example 7. [Figure 17] 1 is an optical microscope photograph of Example 8 under crossed polarized light. [Figure 18] 1 is an optical microscope photograph under crossed polarized light of Example 9. [Figure 19] 1 is an optical microscope photograph of Example 10 under crossed polarized light. [Figure 20] 1 is an optical microscope photograph of Example 11 under crossed polarized light. [Figure 21] 1 is an optical microscope photograph of Example 12 under crossed polarized light. [Figure 22] 1 is an optical microscope photograph of Example 13 under crossed polarized light. [Figure 23] 1 is an optical microscope photograph of Comparative Example 7 under crossed polarized light. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0065] The organic single crystal composite oriented polymer film proposed in the present invention, its preparation method, photoelectric device and its use will be described in more detail below with the accompanying drawings and specific examples. The advantages and features of the present invention will be more clear based on the following description.

[0066] The present invention provides an organic single crystal composite oriented polymer film comprising an organic single crystal and an oriented polymer, in which the oriented polymer is composed of a plurality of polymer fibers of different lengths grown in one direction as shown in Fig. 1(a), and the organic single crystal tightly wraps around the polymer fiber to form effective contact over a large area. The tight wrapping means that the organic single crystal grows by following the undulations of the surface of the polymer fiber, and the opposite concept is that "the low molecular single crystal grows without following the undulations of the surface of the oriented polymer fiber", and the surface of the low molecular single crystal in contact with the fiber is a straight convex surface without any depressions (see Fig. 1(b)).

[0067] The tight wrapping can be confirmed by observing the topography with a scanning electron microscope (SEM) and measuring the height with an atomic force microscope (AFM). As shown in FIG. 1, when a large area of ​​effective contact is formed between the upper organic single crystal and the lower oriented polymer, the surface of the upper organic single crystal is undulated due to the undulations of the lower polymer fiber, and the lower surface of the organic single crystal is indented due to contact with the polymer fiber. Therefore, the upper surface of the upper organic single crystal is directly observed using SEM and AFM to see if there are any undulations, and polyvinyl alcohol (PVA) is mixed into a 10% mass fraction aqueous solution, spin-coated on the composite film at a rotation speed of 2000 rpm for 30 s, dried, and then peeled off to expose the bonding surface between the upper organic single crystal and the polymer fiber, and the bonding surface is observed to see if there are any dents. It is also possible to determine whether the organic single crystal is tightly bonded to the lower polymer fiber by observing whether the side of the organic single crystal is curved with an SEM.

[0068] Furthermore, the tight wrapping may be characterized by measuring the depth of the recess at the bonding surface between the organic single crystal and the polymer fiber by AFM. The recess refers to a narrow width (usually 100 nm or less) where the sample height is lower than the edge position of the width range where the edge sample heights on both sides are almost the same. Since the length of the polymer fiber at the bottom surface is large, the recess is considered to be of similar length. Since the polymer fiber is embedded inside the organic single crystal and a recess is generated on its bottom surface, the difference in height between the lowest position of this recess and the edge position of the recess is the recess depth. When the polymer fiber is not embedded in the organic single crystal, the bottom surface of the organic single crystal is flat or has only a growth step, and there is no recess, that is, the recess depth is 0 nm. Therefore, 10 recesses on the bottom surface of the organic single crystal are randomly selected, and the average depth is measured, which can reflect the state of adhesion between the organic single crystal and the oriented polymer. Preferably, when the recess depth d is 5 nm or more, it is considered that the single crystal and the oriented fiber are firmly adhered to each other.

[0069] The long-range order can be judged primarily by a polarizing microscope. The specific detection method is to place the sample on the sample stage and magnify it to an appropriate magnification such as tens or hundreds of times, and operate the microscope in a transmitted or reflected light mode. If the sample substrate is opaque, the microscope operates in a reflected light mode. When the polarization angle of the polarizing plate of the microscope is perpendicular to the polarization angle of the polarizing plate, the sample stage is rotated, and for example, the organic single crystal and the oriented polymer each show a corresponding light-dark alternating change in the entire field of view, which indicates that both have long-range order. If there is no brightness when the sample stage is rotated under perpendicular polarization, it indicates that both the organic single crystal and the oriented polymer have an amorphous short-range order structure, after excluding the possibility that 1) the main optical axis of the organic single crystal overlaps with the incident direction of the incident light, and 2) the organic single crystal is a cubic system. If there is always brightness when the sample stage is rotated under perpendicular polarization, but there is no corresponding light-dark alternating change, it indicates that the low molecular crystal and the oriented fiber are polycrystalline with no corresponding orientation. A schematic diagram of these three cases is shown in Figure 2.

[0070] The principle by which an optical microscope equipped with orthogonal polarizing plates can be employed to determine whether organic semiconductor crystals and oriented polymer fibers have long-range order is as follows. When polarized incident light is incident on the non-principal optical axis direction of a birefringent crystal, the birefringence phenomenon occurs, and the original polarized light is separated into two lights whose polarization directions are perpendicular to each other, one of which coincides with the polarization direction of the incident light. When observed using a polarizing plate perpendicular to the polarization direction of the polarizing plate, the crystal has a certain brightness in the field of view due to the birefringence phenomenon, and as the sample rotates on the stage, the brightness shows a uniform and consistent light-dark alternating change. Therefore, the long-range order of the system can be determined by observing whether a consistent brightness change appears.

[0071] The long-range order can also be confirmed by selected area electron diffraction, and the detection method is specifically as follows. The sample is cut to an appropriate size, placed on a bare copper net, and then placed in a transmission electron microscope (TEM) for observation. The electron beam acceleration voltage is 200 kV, and the area irradiated by the selected area electron diffraction on the sample is a circular area with a diameter of about 1 μm. In order to avoid damage from the electron beam, it is necessary to snap the diffraction image immediately after moving to an area not irradiated by the electron beam. If two sets of single crystal diffraction patterns are obtained and the diffraction patterns can be calibrated and then respectively corresponded to the unit cell parameters of the organic single crystal and the oriented polymer, it is indicated that the obtained structure has long-range order, and if a diffraction ring or multiple sets (more than two) of diffraction patterns are obtained and the two sets of diffraction patterns correspond to the same material, it is indicated that the obtained structure does not have long-range order. A schematic diagram is shown in Figure 3.

[0072] The principle by which the organic semiconductor crystal and oriented polymer fiber can be judged to have long-range order by using selected area electron diffraction is as follows: When a material has long-range order, each lattice point in the material has the same scattering situation to the electron beam, so that the electron beam is only coherently enhanced at a specific position and shows regularly arranged diffraction spots; on the other hand, when a material does not have long-range order, each lattice point scatters in each direction to the electron beam, so that the electron beam shows multiple sets of diffraction spots, diffraction rings or diffusion rings. Therefore, by observing whether a set of diffraction spots appears by electron beam diffraction, it is judged whether the system has long-range order.

[0073] The uniformity of the orientation of the oriented polymer in a certain direction is represented by the degree of orientation. The degree of orientation Π can be obtained by using a grazing-incidence wide-angle X-ray scattering (GIWAXS) image to irradiate X-rays in the orientation direction, selecting the (100) crystal plane diffraction spot intensity, plotting the azimuth angle, and calculating from the peak shape after fitting using Equation 1. TIFF2025512653000002.tif10170Here, H is the half-width of the diffraction peak, and the unit is degrees (°).

[0074] Here, the organic semiconductor forming the organic single crystal is any one or more selected from linear benzo compounds and derivatives thereof, linear heterobenzo compounds and derivatives thereof, benzothiophene compounds and derivatives thereof, perylene and derivatives thereof, and fullerene and derivatives thereof, and more preferably, 6,13-bis(triisopropylsilylethynyl)pentacene, 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene, 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene (C8-BTBT), fullerene C 60 , perylene.

[0075] The organic polymer forming the oriented polymer is selected from linear conjugated homopolymers, donor-acceptor alternating copolymers, and polymers formed by polymerizing organic semiconductors having a molecular weight of less than 10,000. More preferably, the organic polymer is poly(3-hexylthiophene2,5-diyl), P3HT, PM6, PY-IT, etc.

[0076] The organic single crystal composite oriented polymer film of the present invention further includes a substrate on which the oriented polymer is aligned and grown in one direction. The substrate may be a substrate in the narrow sense, and may be a glass plate, a silicon wafer, a metal oxide (AlO X The substrate may be a hard substrate such as PTFE (Indium Tin Oxide, Indium Tin Oxide, FTO) or a flexible substrate such as polyimide (PI), polyethylene terephthalate (PET), or mica sheet. The substrate may be modified with silane group-containing self-assembly molecules, phosphate group-containing self-assembly molecules, or thiol group-containing self-assembly molecules. The substrate may also be a substrate in the broad sense, that is, when applied to a semiconductor device, the substrate here has an electrode and a transport layer, and polymer fibers can be grown oriented on the transport layer.

[0077] The present invention further provides a method for producing an oriented polymer film in the above organic single crystal composite oriented polymer film, which obtains an oriented organic polymer film on a substrate through spatial restriction and oriented crystallization.

[0078] When producing an oriented polymer film by the spatial restriction and oriented crystallization method, an apparatus shown in FIG. 4 is adopted, which includes a motor 1, a screw rod 2, a ball nut 3, a jig 5 and a temperature gradient hot stage 4. The output shaft of the motor 1 is connected to the screw rod 2, the screw rod 2 is screwed into the ball nut 3, the jig 5 is used to drive the substrate, the temperature gradient hot stage 4 is arranged parallel to the screw rod 2, the jig 5 is fixedly connected to the ball nut 3, and the jig 5 is placed on the temperature gradient hot stage 4. The motor 1 rotates and drives the screw rod 2, the ball nut 3 moves on the screw rod 2, and the jig 5 moves on the temperature gradient hot stage 4, and the moving speed of the jig 5 is equal to the moving speed of the substrate and equal to the solidification speed of the organic polymer. The temperature gradient hot stage 4 may be a Kofler melting point meter, and the substrate is placed on the temperature gradient hot stage 4. The size of the substrate is preferably not larger than the size of the hot stage, but is preferably a square with a side length of 1 to 1.5 cm.

[0079] The method for producing an oriented polymer film using the apparatus shown in FIG. 4 is as follows.

[0080] Preparation of organic polymer solution: The required masses of organic polymer and organic solvent that is solid at room temperature are weighed out, and the organic solvent is melted by heating to produce an organic polymer solution.

[0081] Then, the substrate 6 is sandwiched between the jig 5, and after the temperature reaches equilibrium, a small amount of organic polymer solution is sucked up with a clean glass dropper, 2 to 4 drops are dropped onto the substrate, and a clean glass plate modified with octadecyltrichlorosilane (OTS), which is preheated on a hot stage to a temperature higher than the melting point of the organic solvent, is quickly placed on the droplets of the solution. The motor 1 is started, and the jig 5 together with the substrate 6 is moved at a constant speed toward the low temperature region on the temperature gradient hot stage 4 until the liquid film is completely solidified, and the moving speed of the jig 5 on the temperature gradient hot stage is controlled. It is preferable that the moving speed is 5 to 800 μm / s. The temperature of the initial placement position of the substrate is equal to or higher than the melting point of the organic solvent used. Then, a low-temperature pre-cooled item (e.g., tweezers head, needle head, etc.) is brought into contact with the low-temperature surface of the hot stage of the glass plate, forming a gradient in which the temperature decreases vertically from the substrate to the glass plate covered thereon, and the organic solvent in the liquid film is nucleated and grown on the surface of the upper glass plate under low-temperature induction. When the nucleation of the organic solvent is observed, the pre-cooled item for inducing nucleation is removed. By pressing the glass plate with a weight of m≧100g, the thickness of the liquid film sandwiched between the glass plate and the substrate can be reduced, thereby reducing the thickness of the resulting polymer film, enhancing the spatial restriction effect, and facilitating the formation of an oriented structure.

[0082] The fixture is moved with the substrate toward the low temperature region of the temperature gradient hot stage at a constant speed. During the growth of the solvent crystals, the organic polymer solute is constantly pushed out and concentrated in a very thin area near the substrate surface, and at the same time, the orientation movement in the temperature gradient hot stage causes the orientation crystallization of the organic solvent, so that the polymer exhibits a concentration decrease gradient from the low temperature region to the high temperature region of the temperature gradient hot stage. Therefore, due to the combined action of the space restriction effect and the concentration gradient, the polymer gradually undergoes orientation crystallization from the high temperature to the low temperature region along with the orientation crystallization of the organic solvent, and when the liquid film is completely solidified, a unidirectionally oriented polymer semiconductor film is finally obtained.

[0083] After the liquid film is completely solidified, the glass plate is peeled off, and the solidified liquid film is left in an environment below the melting point of the organic solvent or in a vacuum to sublimate the organic solvent, or the solid organic solvent is removed with an orthogonal solvent, which means a solvent that dissolves the solid organic solvent but does not dissolve the prepared blended polymer, to obtain an oriented polymer film on the substrate.

[0084] The organic solvent for dissolving the organic polymer generally has good solubility for the corresponding organic polymer, is solid at room temperature, and can be easily removed by sublimation or orthogonal solvent dissolution method.Preferably, the organic solvent is a chlorinated aromatic hydrocarbon solvent such as 1,3,5-trichlorobenzene, 1,2,3-trichlorobenzene, 1,2,4,5-tetrachlorobenzene, etc.

[0085] The term "low-temperature pre-cooling" in a low-temperature pre-cooled article is a relative concept, and an article is considered to be low-temperature pre-cooled if the melting point is lower than the melting point of the organic solvent and the difference between the melting point of the organic solvent is 80° C. or more.

[0086] The present invention further provides a method for producing the above organic single crystal composite oriented polymer film, which comprises first producing an oriented polymer according to the above spatial restriction and oriented crystallization method, and then growing an organic single crystal on the oriented polymer by a solution method.

[0087] Using the characterization methods listed above, the present invention will be specifically described with reference to specific examples and comparative examples. Example 1

[0088] The fabrication method of a composite film structure of tips-pentacene-based organic single crystal semiconductor and oriented P3HT fibers includes the following steps: (1) A 575 μm thick P-type with a 300 nm thick silica insulating layer <100> A silicon wafer is prepared, and the BCB-modified substrate is spin-coated onto the silicon substrate. (2) Prepare a 2 mg / mL solution of P3HT in 1,3,5-trichlorobenzene and heat it at 90° C. to completely dissolve it. (3) Place the substrate prepared in step (1) on a Kofler melting point meter (i.e., the temperature gradient hot stage in Figure 4), with the right side of the melting point meter as the low temperature area and the left side as the high temperature area, align the right edge of the substrate at approximately 63 ° C, and press the left side of the substrate against the jig. Use a clean glass plate dropper to drop 2 to 3 drops of the solution prepared in step (2) onto the substrate, quickly cover it with an OTS-modified glass plate preheated to 80 ° C, and press a 100 g weight preheated to 63 ° C on top of it. (4) The servo motor is started, and the substrate is moved to the low-temperature region by the jig at a constant speed of about 40 μm / s, and the 1,3,5-trichlorobenzene is slowly and orientedly solidified. (5) When the liquid film is completely solidified, it is left to stand at about 50° C. for about 3 minutes, and then the substrate is removed from the hot stage and the OTS-modified glass plate covering it is peeled off. (6) The obtained substrate is left at room temperature for one day to volatilize the 1,3,5-trichlorobenzene, thereby obtaining an oriented P3HT film. (7) The substrate manufactured in step (6) is cut into 24 × 24 mm 2 Place a cover glass of 10 mm in diameter and a polyethylene plastic Petri dish cover glass of 35 mm in height, and place a stainless steel embroidery needle on the substrate as a droplet fixture. Place the whole on a hot stage at 25 °C for 10 min to equilibrate the temperature, and leave the Petri dish on the hot stage throughout the growth of the organic single crystals. (8) Prepare a 0.4 mg / mL solution of tips-pentacene in n-hexane and sonicate for 20 min to completely dissolve the solute. (9) Aspirate 20 μL of the solution prepared in step (8) with a pipette gun and gently drip it onto the needle on the substrate, taking care not to let the droplet slide off the substrate. Then, close the lid of the dish immediately and seal the dish with the sealing membrane. After leaving it for about 10 min, when the solvent has completely evaporated, the dish is opened, the droplet fixing object is removed, and a tips-pentacene single crystal array composite P3HT oriented fiber film is obtained on the substrate. To characterize the topography and structure of the organic single crystal composite oriented polymer film, optical microscopes, scanning electron microscopes, and atomic force microscopes were used to observe. The topography of the composite film obtained is shown in Figure 5(a). From Figure 5(a), it was found that the organic semiconductor was covered on the oriented P3HT fibers as strip-like crystals. In addition, from the SEM topography of the bonding surface between the organic single crystal and the oriented polymer (Figure 8(a)), the topography of the surface of the organic single crystal (Figure 8(b)), and the junction between the side of the organic single crystal and the oriented polymer (Figure 8(c)), it was found that the tips-pentacene single crystal was firmly attached to the oriented P3HT fibers. To characterize the long-range order of the organic single crystal composite oriented polymer semiconductor film, the film was observed by selected-area electron diffraction in a transmission electron microscope using a polarizing microscope. As shown in the polarizing microscope images in Figures 2(a) and (b), synchronous light-dark changes were observed under orthogonal polarization. As shown in Figure 3(a), the selected-area electron diffraction showed only one pair of Tips-pentacene single crystal diffraction spots and P3HT diffraction spots, which indicated that the film had long-range order as a whole. To characterize the photophysical properties of the organic single crystal composite oriented polymer semiconductor film, the film was tested using a fluorescence spectrometer. As shown in Figure 9(a), the composite film showed obvious fluorescence quenching phenomenon. From Figure 10(a), it was found that the obtained fluorescence lifetime was 109ps. As shown in Figure 6(a), the electron diffraction pattern of the obtained P3HT film shows diffraction spots like those of a single crystal, and there is no noticeable diffraction ring, indicating good orientation in the thickness direction of the entire film. When X-rays are incident in the orientation direction and the crystal plane diffraction intensity vs. azimuth angle φ of the 2D GIWAXS image (100) is plotted, a P3HT oriented polymer with an orientation degree of 87% is obtained, as shown in Figure 7. In addition, from Figure 1(c), it is found that the recess depth of the bottom surface of the obtained Tips-pentacene single crystal is 7.3 nm. Example 2

[0089] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film in this example refers to Example 1, but the concentration of the P3HT solution is 5 mg / mL. The method of characterizing the topography and structure is the same as that of Example 1. As shown in Figure 11, the obtained composite film exhibits synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the Tips-pentacene single crystal is 9.2 nm. Example 3

[0090] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The manufacturing method of the organic single crystal composite oriented polymer film of this embodiment refers to Example 1, but when growing Tips-pentacene single crystals, a hot stage is placed in a glove box with a water content of less than 5 ppm at a preheating temperature of 5 ° C., and the Tips-pentacene-hexane solution is dropped, and then the dish is covered with a lid, and there is no need to seal it with a sealing membrane. The method of characterizing the topography and structure is the same as that of Example 1. As shown in Figure 12, the obtained composite film exhibits synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the Tips-pentacene single crystal is 6.3 nm. Example 4

[0091] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The manufacturing method of the organic single crystal composite oriented polymer film of this embodiment refers to Example 1, but when growing Tips-pentacene single crystals, Tips-pentacene is dissolved in n-heptane at a concentration of 0.4 mg / mL, and the preheating temperature of the hot stage is 38 ° C. The method of characterizing the topography and structure is the same as that of Example 1. As shown in Figure 13, the obtained composite film exhibited synchronous brightness and darkness with orthogonal polarized light, and the recess depth of the bottom surface of the Tips-pentacene single crystal was 5.5 nm. Example 5

[0092] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film in this example refers to Example 1, but the substrate is a silicon wafer with a 300 nm thick silica insulating layer that does not require BCB modification. The method of characterizing the topography and structure is the same as that of Example 1. As shown in Figure 14, the obtained composite film exhibits synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the Tips-pentacene single crystal is 5.3 nm. Example 6

[0093] The fabrication method of the composite film structure of Tips-TAP-based organic single crystals and oriented P3HT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film in this example refers to Example 1, but the substrate is a silicon wafer with a 300 nm thick silica insulating layer modified with c-PMMA, and when growing Tips-TAP single crystals, Tips-TAP is prepared in a 0.3 mg / mL n-hexane solution. The methods for characterizing the topography, structure, and properties are the same as those in Example 1. The topography of the obtained composite film is shown in Figure 5(g), and the obtained composite film has an orthogonal polarized microscope image shown in Figure 15. From these figures, it can be seen that the composite film exhibits synchronous brightness and darkness under orthogonal polarized light, and the recess depth of the bottom surface of the Tips-TAP single crystal is 7.6 nm. The steady-state fluorescence shows significant fluorescence quenching, as shown in Figure 9(b). The fluorescence lifetime calculated from the transient fluorescence fitting curve in Figure 10(b) was 112 ps. Example 7

[0094] The fabrication method of the composite film structure of Tips-TAP-based organic single crystals and oriented P3HT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film in this example refers to Example 1, but the substrate is a silicon wafer with a silica insulating layer modified with c-PMMA, and when growing Tips-TAP single crystals, Tips-TAP is prepared in a 0.3 mg / mL meta-xylene solution, and the preheating temperature of the hot stage is 45 ° C. The methods of characterizing the topography, structure, and properties are the same as those in Example 1. As shown in Figure 16, the obtained composite film exhibits synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the Tips-TAP single crystal is 6.9 nm. Example 8

[0095] The fabrication method of a composite film structure of tips-pentacene-based organic single crystal semiconductor and oriented P3HT fibers includes the following steps: The method for producing oriented polymer fibers in this example refers to steps (1 to 6) in Example 1. Furthermore, organic single crystals are produced by a bar-coating method, that is, a meniscus coating method. (1) Prepare a 0.5 mg / mL n-heptane solution of tips-pentacene and dissolve it thoroughly using ultrasound. (2) The distance between the coating bar and the substrate coated with the oriented polymer is adjusted to 200±5 μm. (3) After preheating the substrate coated with the oriented polymer at 38° C. for 10 minutes, 10 μL of the solution prepared in step (1) is dropped onto the coating rod to fill the gap between the coating rod and the substrate with the solution. (4) The coating rod is controlled to move at a constant speed of 400±5 μm / s in a fixed direction to coat the substrate with the solution. (5) Using dust-free paper to suck up excess liquid between the coating rod and the substrate produces organic single crystals on the oriented polymer. The methods for characterizing the topography, structure, and properties are the same as those in Example 1. The topography of the obtained composite film is shown in Figure 5(i), and as shown in Figure 17, the composite film exhibited synchronous brightness under orthogonal polarized light, and the depression depth of the bottom surface of the Tips-pentacene single crystal was 8.0 nm. Example 9

[0096] The manufacturing method of the composite film structure of C8-BTBT-based organic single crystals and oriented P3HT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film in this example refers to Example 1, except that the organic semiconductor solution is a 4-methyl-2-pentanone solution of 0.6 mg / mL C8-BTBT, and the crystal growth temperature is 55°C. The methods of characterizing the topography, structure, and properties are the same as those in Example 1. As shown in Figure 18, the obtained composite film exhibited synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the C8-BTBT single crystal was 7.4 nm. Example 10

[0097] The manufacturing method of a composite film structure of perylene-based organic single crystals and oriented P3HT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film of this example refers to Example 1, except that the organic semiconductor solution is a 0.4 mg / mL perylene meta-xylene solution, the crystal growth temperature is 35°C, and no sealing is performed with a sealing membrane. The methods of characterizing the topography, structure, and properties are the same as those of Example 1. As shown in Figure 19, the obtained composite film exhibits synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the perylene single crystal is 7.1 nm. Example 11

[0098] The manufacturing method of the composite film structure of C8-BTBT-based organic single crystals and oriented PM6 fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film in this example refers to Example 9, except that the organic polymer solution is 2 mg / mL PM6 in 1,3,5-trichlorobenzene, and the organic semiconductor solution is 0.6 mg / mL C8-BTBT in n-hexane. The methods for characterizing the topography, structure, and properties are the same as those in Example 1. The obtained oriented polymer film has an orientation degree of 89%, and as shown in Figure 20, the composite film exhibits synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the C8-BTBT single crystal is 6.7 nm. Example 12

[0099] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented PY-IT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film in this example refers to Example 1, but the organic polymer solution is a 1,2,4,5-tetrachlorobenzene solution of 2 mg / mL PY-IT. The methods of characterizing the topography, structure, and properties are the same as those in Example 1. The obtained oriented polymer film has an orientation degree of 78%, and as shown in Figure 21, the composite film exhibits synchronous brightness under orthogonal polarized light, and the recess depth of the bottom surface of the Tips-pentacene single crystal is 6.2 nm. Example 13

[0100] C 60 The method for preparing a composite film structure of P3HT-based organic single crystal semiconductor and oriented P3HT fibers includes the following steps: The method for producing the organic single crystal composite oriented polymer film in this embodiment is the same as that in Example 1, except that the organic semiconductor solution is 0.4 mg / mL C 60 The crystal growth temperature is 30° C. The methods for characterizing the topography, structure, and properties are the same as those in Example 1. As shown in FIG. 22, the obtained composite film exhibits synchronous brightness under cross-polarized light, and C 60 The depression depth on the bottom surface of the single crystal was 7.9 nm. Example 14

[0101] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The method for producing the organic single crystal composite oriented polymer film of this embodiment is the same as that of Example 1, but the moving speed of the jig during the production of the oriented polymer film is 5 μm / s. Example 15

[0102] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The method for producing the organic single crystal composite oriented polymer film of this embodiment refers to Example 1, but the moving speed of the jig when producing the oriented polymer film is 300 μm / s. Example 16

[0103] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The method for producing the organic single crystal composite oriented polymer film of this embodiment is the same as that of Example 1, but the moving speed of the jig during the production of the oriented polymer film is 800 μm / s. Example 17

[0104] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The method for producing the organic single crystal composite oriented polymer film of this embodiment is the same as that of Example 1, except that Tips-pentacene is prepared into a 0.2 mg / mL n-hexane solution. Example 18

[0105] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The preparation method of the organic single crystal composite oriented polymer film of this embodiment is the same as that of Example 1, except that Tips-pentacene is prepared into a 0.8 mg / mL n-hexane solution. Example 19

[0106] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The method for producing the organic single crystal composite oriented polymer film of this embodiment is the same as that of Example 8, but the moving speed of the coating rod during the production of the organic single crystal film is 20 μm / s. Example 20

[0107] The manufacturing method of the composite film structure of tips-pentacene-based organic single crystals and oriented P3HT fibers includes the following steps: The method for producing an organic single crystal composite oriented polymer film in this embodiment is similar to that in Example 8, and the moving speed of the coating rod during the production of the organic single crystal film is 800 μm / s. Comparative Example 1

[0108] The manufacturing method of a composite film structure of tips-pentacene-based organic polycrystals and oriented P3HT fibers includes the following steps: The manufacturing method of the organic polycrystalline composite oriented polymer semiconductor film of Comparative Example 1 refers to Example 1, but the concentration of the P3HT solution is 10 mg / mL, and the same organic solvent as in Example 1 is used for dissolution. As shown in Figure 5(b), the tips-pentacene film was observed under a microscope and was determined to be an organic polycrystalline film. Comparative Example 2

[0109] The fabrication method of a composite film structure of tips-pentacene-based organic polycrystalline semiconductor and oriented P3HT fibers includes the following steps: The manufacturing method of the organic polycrystalline composite oriented polymer semiconductor film of Comparative Example 2 refers to Example 1, but the preheating temperature of the hot stage when growing the tips-pentacene organic polycrystalline is 17°C. As shown in Figure 5(c), the tips-pentacene film was observed under a microscope and was determined to be an organic polycrystalline film. Comparative Example 3

[0110] The fabrication method of a composite film structure of tips-pentacene-based organic polycrystalline semiconductor and oriented P3HT fibers includes the following steps: The manufacturing method of the organic single crystal composite oriented polymer semiconductor film of Comparative Example 2 refers to Example 1, but the concentration of the Tips-pentacene solution is 1 mg / mL. As shown in Figure 5 (d), the Tips-pentacene film was observed under a microscope and was determined to be an organic polycrystalline film. Comparative Example 4

[0111] The fabrication method of a composite film structure of tips-pentacene-based organic polycrystalline semiconductor and oriented P3HT fibers includes the following steps: The manufacturing method of the organic polycrystalline composite oriented polymer semiconductor film of Comparative Example 4 refers to Example 1, but the solvent used for the tips-pentacene solution is cyclohexane. As shown in Figure 5 (e), the tips-pentacene film was observed under a microscope and was determined to be a discontinuous organic polycrystalline film. Comparative Example 5

[0112] The fabrication method of a composite film structure of tips-pentacene-based organic polycrystalline semiconductor and oriented P3HT fibers includes the following steps: The manufacturing method of the organic polycrystalline composite oriented polymer semiconductor film of Comparative Example 5 refers to Example 1, but the moving speed of the jig when manufacturing the P3HT oriented fiber is 1000 μm / s. As shown in Figure 5 (f), the Tips-pentacene film was observed under a microscope and was determined to be a discontinuous organic polycrystalline film. Comparative Example 6

[0113] The fabrication method of the composite film structure of Tips-TAP-based organic single crystal semiconductor and oriented P3HT fibers includes the following steps: The method for producing the organic single crystal composite oriented polymer semiconductor film of Comparative Example 6 refers to Example 6, but the Tips-TAP solution is prepared using cyclohexane. The Tips-TAP film was observed under a microscope and was determined to be a discontinuous organic polycrystalline film, as shown in Figure 5(h). Comparative Example 7

[0114] The fabrication method of a composite film structure of tips-pentacene-based organic single crystal semiconductor and disordered P3HT fibers includes the following steps: The preparation method of the organic single crystal in Comparative Example 7 refers to Example 1, but the preparation method of the P3HT disordered film is as follows. The film is completely dissolved by heating to 60 ° C using a mixed solvent of o-dichlorobenzene and n-heptane with a volume ratio of 3:2, and then left at room temperature for one day, and the solution is spin-coated on a clean silicon wafer substrate at a rotation speed of 8000 rpm. The tips-pentacene film was observed with a polarizing microscope and showed synchronous light and dark, so that it could be determined to be an organic single crystal film as shown in Figure 23. As shown in Figure 6 (b), the selected area electron diffraction image showed diffraction rings, so that the disordered nature of P3HT could be determined. Its transient fluorescence characteristics were characterized as shown in Figure 10 (a), and the fluorescence lifetime was 150 ps. Comparative Example 8

[0115] The method for fabricating a blend film structure of tips-pentacene-based organic polycrystal and P3HT includes the following steps. (1) A 575 μm thick P-type with a 300 nm thick silica insulating layer <100> A silicon wafer is prepared, and the BCB-modified substrate is spin-coated onto the silicon substrate. (2) Prepare a chlorobenzene solution of P3HT and Tips-pentacene at a mass ratio of 1:7 and a concentration of 15 mg / mL, and heat to 60°C to completely dissolve. (3) Place the BCB-modified substrate from step (1) on a 1 × 1 cm 2 Cut to size and place on spin coater. (4) The solution prepared in step (2) is dropped onto the substrate, and after spreading over the substrate, the spin coater is started and the substrate is spin-coated at 1000 rpm for 60 s to obtain a blend film of the tips-pentacene organic semiconductor and P3HT. The blend film consists of disordered P3HT and Tips-pentacene polycrystals, and the method of characterizing its structure and properties is the same as in Example 1. The electron diffraction pattern shown in Figure 3(b) is a diffraction ring, indicating that the obtained film structure has no long-range order. The transient fluorescence properties of the film were characterized as shown in Figure 10(a), and the fluorescence lifetime was 571 ps. Comparative Example 9

[0116] The fabrication method of the composite film structure of Tips-TAP-based organic single crystals and disordered P3HT fibers includes the following steps: The manufacturing method of the organic single crystal composite oriented polymer film of Comparative Example 9 is the same as that of Comparative Example 7. The transient fluorescence characteristics are shown in FIG. 10(b), and the fluorescence lifetime is 154 ps. Comparative Example 10

[0117] The fabrication method of the blend film structure of Tips-TAP-based organic semiconductor and P3HT includes the following steps. The manufacturing method of the blend film of organic semiconductor and P3HT in Comparative Example 10 was the same as that in Comparative Example 8, but the spin-coating solution was a chlorobenzene solution prepared by mixing P3HT and Tips-TAP in a mass ratio of 1:7 to a total concentration of 15 mg / mL. The transient fluorescence characteristics were characterized as shown in Figure 10(b), and the fluorescence lifetime was 240 ps. The manufacturing conditions for the samples of the above examples and comparative examples are summarized in the following table.

[0118] The preparation conditions for the sample prepared using the droplet immobilization crystallization method are as follows: TIFF2025512653000003.tif234170TIFF2025512653000004.tif235170TIFF2025512653000005.tif235170TIFF2025512653000006.tif234170

[0119] The manufacturing conditions for the sample produced by growing an organic single crystal using the meniscus coating method are as follows. TIFF2025512653000007.tif146170

[0120] In Examples 1 to 7 and Comparative Examples 1 to 6, the effects of various manufacturing conditions on the crystallization of organic semiconductors were investigated. Depending on the substrate modification layer, organic semiconductor single crystals may grow by forming a nucleus at the gas-liquid interface or at the solid-liquid interface, so it is necessary to select an appropriate substrate and modification layer. In view of Examples 1, 5, and 6, it is preferable that the substrate is modified with c-PMMA or BCB.

[0121] In order for the single crystal to cross the oriented polymer semiconductor fibers previously dispersed on the substrate, the organic semiconductor single crystal must be nucleated and grown at the gas-liquid interface, and the polymer fibers on the substrate must not have excessive undulations, otherwise it will affect the progress of mass transfer during crystal growth. In addition, the undulations of the oriented polymer fibers increase with an increase in the concentration of the polymer solution, and the aggregation of the fibers during rapid solidification is serious, resulting in relatively large undulations. Therefore, it is necessary to control the organic polymer solution concentration and the solidification rate. It was revealed that for Examples 1-2 and Comparative Example 1, the concentration of the organic polymer solution must be controlled to 2-5 mg / ml, and for Example 1, Examples 14-16, and Comparative Example 5, the solidification rate must be controlled to 5-800 μm / s. Under these conditions, an organic semiconductor single crystal can be formed on the oriented polymer fibers.

[0122] In addition, the concentration of the organic semiconductor solution, the crystal growth temperature, and the selection of the solvent affect the nucleation rate and crystal growth rate of the organic semiconductor. If the nucleation rate is too high and the solvent evaporates too fast, the crystal growth cannot keep up with the movement of the liquid film, which increases the tendency of the small molecule organic semiconductor to form polycrystals. On the other hand, if the nucleation rate is too low and the solvent evaporates too slowly, the small molecule organic semiconductor is prone to uniform nucleation inside the solution, forming coarse crystals, and the contact with the polymer fiber below is not tight. Therefore, it is necessary to control the concentration of the organic semiconductor solution, the crystal growth temperature, and the solvent. Only when the solution concentration is 0.2-0.8 mg / ml (Examples 1, 6, 9, 11, 17-18, Comparative Example 3), the crystal growth temperature, and the corresponding suitable solvent (Examples 1, 3, 4, 6, 7, 9, Comparative Examples 2-4, 6) can obtain a small molecule organic semiconductor single crystal that is tightly adhered to the oriented polymer fiber.

[0123] The fluorescence spectrum can be used to characterize the photophysical properties of photoelectric devices to determine the capability of long-range order in photoelectric conversion. When incident light is irradiated onto a sample, photogenerated excitons are generated in the sample, some of which can migrate to the heterojunction interface and dissociate into free carriers under the action of the built-in electric field, while some of the photogenerated excitons recombine before migrating to the heterojunction interface, emitting photons again and being detected by the detector. Thus, in the steady-state fluorescence, it is detected that the fluorescence intensity of the composite system is decaying, indicating that more photogenerated excitons are dissociated than in the single-component system, i.e., the photoelectric conversion efficiency is higher (see Figure 9). In the transient fluorescence, it is shown that the faster the decay rate of the fluorescence of the system, the faster the migration rate of the photogenerated excitons and the higher the dissociation efficiency, i.e., the higher the photoresponsiveness and photoelectric conversion efficiency. The decay rate of the fluorescence is defined as the fluorescence lifetime τ, which can be obtained by exponentially fitting the transient fluorescence curve. TIFF2025512653000008.tif27170

[0124] Examples 1 and 6 and Comparative Examples 7 to 10 investigated the effects of different degrees of order in the composite film on the photophysical properties of the photoelectric device. From FIG. 9, Examples 1 and 6 showed obvious fluorescence quenching phenomenon compared with the single-oriented P3HT fiber, indicating the existence of effective charge transfer process in the long-range ordered composite film. From FIG. 10, the fluorescence lifetime tends to decay obviously with the increase of the long-range order of the composite film (fluorescence lifetime of Example 1 is 109 ps, fluorescence lifetime of Comparative Example 7 is 150 ps, ​​fluorescence lifetime of Comparative Example 8 is 571 ps, fluorescence lifetime of Example 6 is 112 ps, fluorescence lifetime of Comparative Example 9 is 154 ps, fluorescence lifetime of Comparative Example 10 is 240 ps), suggesting that the improvement of the long-range order increases the exciton diffusion distance and carrier mobility, further improving the photoelectric conversion ability of the composite film, thereby realizing the manufacture of high-performance photoelectric devices.

[0125] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the present invention is not limited to the above embodiment. Even if various modifications are made to the present invention, these modifications are included in the scope of protection of the present invention if they are within the scope of the claims of the present invention and the scope of the technology equivalent thereto. [Explanation of symbols]

[0126] 1 - motor, 2 - threaded rod, 3 - ball nut, 4 - temperature gradient hot stage, 5 - fixture, 6 - substrate

Claims

1. An organic single crystal composite oriented polymer film comprising an oriented polymer, which is a polymer fiber in which an organic polymer has been aligned and grown in one direction, and an organic single crystal tightly wrapping around the polymer fiber.

2. The organic single crystal composite oriented polymer film according to claim 1, characterized in that the tightly wrapped structure means that the organic semiconductor single crystals grow in close contact with the surfaces of the polymer fibers.

3. The organic single crystal composite oriented polymer film of claim 1, characterized in that the tight wrapping is detected by observing whether the surface microtopography of the organic single crystal is undulating and whether there is a depression at the bonding surface between the organic single crystal and the oriented polymer.

4. The tight wrapping is detected by measuring the depth of the recess on the bonding surface between the organic single crystal and the oriented polymer, the depth being the difference in height between the lowest point of the recess and the edge position of the recess, and 10 recesses on the bonding surface between the organic single crystal and the oriented polymer are randomly selected and the average depth is measured. The organic single crystal composite oriented polymer film described in claim 3.

5. The organic single crystal composite oriented polymer film according to claim 4, wherein the recess depth is 5 nm or more.

6. The organic single crystal composite oriented polymer film of claim 3, characterized in that a sample of the bonding surface between the organic single crystal and the oriented polymer is produced by spin-coating an aqueous polyvinyl alcohol solution on the upper surface of the organic single crystal composite oriented polymer film at a rotation speed of 2000 rpm for 30 seconds, and then peeling off the polyvinyl alcohol after drying to expose the bonding surface.

7. The organic single crystal composite oriented polymer film according to claim 2, wherein the organic semiconductor is one or more selected from the group consisting of linear benzo compounds and derivatives thereof, linear heterobenzo compounds and derivatives thereof, benzothiophene compounds and derivatives thereof, perylene and derivatives thereof, and fullerene and derivatives thereof.

8. The organic single crystal composite oriented polymer film according to claim 2 or 7, characterized in that the organic semiconductor is 6,13-bis(triisopropylsilylethynyl)pentacene, 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene, 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene, fullerene, or perylene.

9. The organic single crystal composite oriented polymer film according to claim 1, wherein the organic polymer is a linear conjugated homopolymer, a donor-acceptor alternating copolymer, or a polymer formed by polymerizing an organic semiconductor having a molecular weight of less than 10,000.

10. 10. The organic single crystal composite oriented polymer film according to claim 1 or 9, wherein the organic polymer is poly(3-hexylthiophene-2,5-diyl), PM6, or PY-IT.

11. The organic single crystal composite oriented polymer film according to claim 1 , further comprising a substrate on which the polymer fibers are grown and aligned in one direction.

12. 12. The organic single crystal composite oriented polymer film according to claim 11, wherein the substrate is a glass plate, a silicon wafer, a metal oxide, a polyimide, a polyethylene terephthalate, or a mica sheet.

13. The organic single crystal composite oriented polymer film according to claim 11, characterized in that the substrate is a substrate modified with a silane group-containing self-organizing molecule, a phosphate group-containing self-organizing molecule, or a thiol group-containing self-organizing molecule.

14. 14. The organic single crystal composite oriented polymer film according to claim 11 or 13, characterized in that the substrate is a substrate modified with crosslinked polymethyl methacrylate or benzocyclobutene.

15. First, step A1 of dissolving an organic polymer in an organic solvent to prepare an organic polymer solution; Spatial confinement and oriented crystallization method: placing a substrate on a temperature gradient hot stage, and setting the temperature of the substrate at its initial position on the temperature gradient hot stage between the melting point and the boiling point of the organic solvent; Dropping the organic polymer solution onto the substrate, and covering the solution droplets with a preheated sheet-like member; Before moving the substrate, a low-temperature pre-cooled article is brought into contact with the surface of the sheet-like member that is closer to the low-temperature region of the temperature gradient hot stage, forming a gradient in which the temperature decreases vertically from the substrate to the sheet-like member, and causing the organic solvent in the liquid film to nucleate and grow on the surface of the sheet-like member under low-temperature induction. When the nucleation of the organic solvent is observed, the low-temperature pre-cooled article is removed. Next, step A2 of moving the substrate toward a region having a lower temperature than the initial position on the temperature gradient hot stage while controlling the moving speed of the substrate.

16. 16. The method for producing an oriented polymer film according to claim 15, wherein the surface of the sheet-like member which comes into contact with the organic polymer solution is modified with octadecyltrichlorosilane.

17. The method for producing an oriented polymer film according to claim 16, characterized in that the article pre-cooled at a low temperature is lower than the melting point of the organic solvent and has a difference of more than 80°C from the melting point of the organic solvent.

18. 16. The method for producing an oriented polymer film according to claim 15, wherein the sheet-like member is pressed with a weight of m≧100 g while the substrate is moving.

19. 16. The method for producing an oriented polymer film according to claim 15, wherein the moving speed of the substrate is 5 to 800 μm / s.

20. 16. The method for producing an oriented polymer film according to claim 15, wherein the substrate is a glass plate, a silicon wafer, a metal oxide, a polyimide, a polyethylene terephthalate, or a mica sheet.

21. 16. The method for producing an oriented polymer film according to claim 15, wherein the organic solvent has a melting point of less than 30° C., is easy to heat, or can be easily removed by orthogonal solvent dissolution method.

22. The method for producing an oriented polymer film according to claim 21, wherein the organic solvent is a chlorinated aromatic hydrocarbon solvent.

23. 23. The method for producing an oriented polymer film according to claim 22, wherein the organic solvent is 1,3,5-trichlorobenzene, 1,2,3-trichlorobenzene, or 1,2,4,5-tetrachlorobenzene.

24. 16. The method for producing an oriented polymer film according to claim 15, wherein the organic polymer is a polymer formed by polymerizing a linear conjugated homopolymer, a donor-acceptor alternating copolymer, or an organic semiconductor having a molecular weight of less than 10,000.

25. The method for producing an oriented polymer film according to claim 15 or 24, wherein the organic polymer is poly(3-hexylthiophene-2,5-diyl), PM6, or PY-IT.

26. Step S1 of producing an oriented polymer film by the method for producing an oriented polymer film according to any one of claims 15 to 25; The method for producing an organic single crystal composite oriented polymer film according to any one of claims 1 to 14, further comprising a step S2 of growing an organic single crystal on the oriented polymer.

27. The method for producing an organic single crystal composite oriented polymer film according to claim 26, characterized in that the concentration of the organic polymer solution is 0 to 5 mg / mL.

28. The method for producing an organic single crystal composite oriented polymer film according to claim 27, characterized in that the concentration of the organic polymer solution is 2 to 4 mg / mL.

29. 27. The method for producing an organic single crystal composite oriented polymer film according to claim 26, wherein in step S2, organic single crystals are grown on the oriented polymer by a solution method.

30. Specifically, the step of growing an organic single crystal by the solution method includes: First, step S201 of dissolving an organic semiconductor in a solvent to prepare an organic semiconductor solution; The method for producing an organic single crystal composite oriented polymer film according to claim 29, further comprising: a step S202 of growing an organic single crystal on the oriented polymer by any one of a droplet fixed crystallization method and its variants, and a meniscus coating method.

31. The step of producing a single crystal by the droplet fixing crystallization method specifically includes: The method for producing an organic single crystal composite oriented polymer film according to claim 30, further comprising step S202: placing a substrate on which an oriented polymer has been produced in a container, placing a droplet fixing object at the center of the substrate on which an oriented polymer has been produced, preheating the entire container, dropping an organic semiconductor solution onto the droplet fixing object at this preheated temperature, and obtaining an organic single crystal when the evaporation of the solvent in the droplet is completed.

32. The method for producing an organic single crystal composite oriented polymer film according to claim 31, wherein the droplet fixing object is a silicon wafer, a needle, or a metal rod.

33. The method for producing an organic single crystal composite oriented polymer film according to claim 30, characterized in that the modified droplet fixing crystallization method is to place the substrate on which the oriented polymer is produced in a container, tilt the substrate by 0.1 to 5 degrees, preheat the entire container, and then drop the organic semiconductor solution onto the droplet fixing object, quickly seal the container, and obtain an organic single crystal when the solvent in the droplet is completely evaporated under the preheating temperature conditions.

34. Specifically, the step of growing an organic single crystal by the meniscus coating method includes: After adjusting the distance between the coating tool and the substrate on which the oriented polymer is produced to 100 to 150 μm, the substrate on which the oriented polymer is produced is preheated, and the organic semiconductor solution is injected into the gap between the coating tool and the substrate at this preheated temperature, and then the coating tool is moved at a constant speed parallel to the substrate to shear the organic semiconductor solution, and after coating is completed, the excess organic semiconductor solution is sucked up, or The method for producing an organic single crystal composite oriented polymer film according to claim 30, comprising immersing a substrate on which an oriented polymer has been produced into an organic semiconductor solution, pulling up the substrate, forming a meniscus between the pulled-up substrate and the organic semiconductor solution, and completely removing the substrate from the organic semiconductor solution.

35. The method for producing an organic single crystal composite oriented polymer film according to claim 34, characterized in that the coating tool is a scraper, a blade, a smooth rod, a coil rod, a brush, or a bead.

36. The method for producing an organic single crystal composite oriented polymer film according to claim 34, characterized in that the moving speed of the coating tool is 10 to 800 μm / s.

37. 31. The method for producing an organic single crystal composite oriented polymer film according to claim 30, wherein in step S201, the solubility of the organic semiconductor in the solvent is greater than 0.2 mg / mL, and the solvent does not dissolve the oriented polymer.

38. The method for producing an organic single crystal composite oriented polymer film according to claim 37, characterized in that in step S201, the solvent is one or a mixture of n-hexane, n-heptane, meta-xylene, and 4-methyl-2-pentanone.

39. The method for producing an organic single crystal composite oriented polymer film according to claim 30, wherein the concentration of the organic semiconductor solution is 0.1 to 0.8 mg / mL.

40. A photoelectric device comprising an organic single crystal composite oriented polymer film according to any one of claims 1 to 14, or an organic single crystal composite oriented polymer film produced by the method according to any one of claims 26 to 39.

41. Use of the organic single crystal composite oriented polymer film according to any one of claims 1 to 14, the organic single crystal composite oriented polymer film produced by the method according to any one of claims 26 to 39, and the photoelectric device according to claim 40 in the fields of organic photovoltaic power generation, organic photodetection, organic display, transportation logistics, mining metallurgy, environment, medical equipment, explosion-proof detection, food, water treatment, medicine, and biology.

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