Compound, use of at least one such compound in an optoelectronic component, and an optoelectronic component comprising at least one such compound

Abstract

The present invention relates to compounds of general formula I, to optoelectronic components comprising compounds of said type, and to the use of such compounds in optoelectronic components. JPEG2023540942000047.jpg49170

Description

Technical Field

[0001] The present invention relates to compounds of general formula I, the use of at least one such compound in optoelectronic components, and optoelectronic components comprising at least one such compound.

Background Art

[0002] In organic electronics, interconnections composed of conductive polymers or small organic molecules are used. Organic semiconductors can perform various functions of electronic components such as, for example, charge transport, radiation absorption, or radiation emission, and can simultaneously perform one or more functions. Optoelectronic components can be, for example, displays, data memories, or transistors, or organic optoelectronic components such as, in particular, photovoltaic devices, especially solar cells, and photodetectors, which have a photoactive layer. Charge carriers in the photoactive layer, more specifically, bound electron-hole pairs (excitons), are generated upon incidence of electromagnetic radiation. Excitons move by diffusion to this type of interface where the electrons and holes are separated from each other. A substance that takes in electrons is called an acceptor, and a substance that takes in holes is called a donor.

[0003] Organic optoelectronic components enable the conversion of electromagnetic radiation into an electric current by utilizing the photovoltaic effect. Such conversion of electromagnetic radiation requires an absorber material that exhibits excellent absorption characteristics.

[0004] Organic optoelectronic components are known from the prior art. Patent Document 1 discloses a photoactive component, in particular a solar cell, consisting of one or more organic layers of pi, ni, and / or pin diodes laminated on one another.

[0005] One of the structures known from the prior art for organic solar cells consists of a pin or nip diode (Non-Patent Document 1 and Patent Document 2). In this case, a pin-type solar cell usually consists of a substrate on which a transparent electrode, a p-layer, an i-layer, an n-layer, and a counter electrode are arranged. Here, n and p represent the doping of n and p, respectively, which increase the density of free electrons or holes in the thermal equilibrium state. Such layers should be mainly understood as transport layers. The name of the i-layer represents an undoped layer (intrinsic layer) having an absorber material or a mixture of two or more absorber materials. One or more i-layers can be composed of a mixture of two or more materials (bulk heterojunction). The absorber material, and thus the absorber, particularly refers to a compound that absorbs light in a specific wavelength range. Therefore, the absorber layer is particularly understood to be a layer in an optoelectronic component containing at least one absorber material.

[0006] In the prior art, many polymeric and non-polymeric absorber materials for organic photovoltaic devices in the red and near-infrared (NIR) range of about 600 to about 1400 nm have been disclosed. In the technical field of non-polymeric absorber materials, it has been proven that materials of the BODIPY classification are particularly suitable for the near-infrared spectral range. In particular, the use of meso-CF3 substituted derivatives has been established, resulting in an appropriate energy layer and thus a high photovoltaic power related to the long-wave absorption range.

[0007] Patent Document 3 discloses the use of pyrrolopyrrole-based compounds in organic electronic devices.

[0008] Patent Document 4 discloses an organic semiconductor including a plurality of layers, wherein at least one of the layers contains a material having an Azabodipy skeleton.

[0009] Non-Patent Document 2 discloses a BODIPY structure as a fluorescent dye in which the meso position is unsubstituted or has a fluorinated alkyl chain.

[0010] Non-Patent Document 3 discloses a BODIPY structure having a perfluorinated alkyl chain at the meso position, which can be used as an NIR donor material in organic solar cells.

[0011] Absorbers in the red and near-infrared regions known from the prior art are not satisfactory. Although known absorber materials are suitable for the photoactive layer of an organic optoelectronic device, i.e., an organic solar cell, it is necessary to improve the absorption characteristics of the absorber material, particularly in relation to conventional silicon-based solar cells, in order to enhance the competitiveness of the organic optoelectronic device. One of the factors determining the efficiency of an organic optoelectronic device is the absorption behavior of the organic material, i.e., the absorber material, in the photoactive layer. Furthermore, a fundamental problem in vacuum processing is that vacuum evaporation has limited volatility of organic materials due to insufficient thermal stability, and as a result, the selection of absorbers is significantly restricted. Due to their low melting and decomposition points, the volatility, and thus the achievable deposition rate, is limited, and in principle, many materials that are suitable as absorbers cannot be employed on an industrial scale.

Prior Art Documents

Patent Documents

[0012]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Documents

[0013]

Non-Patent Document 1

[0014] Therefore, the present invention is based on the object of providing a compound that does not exhibit the described drawbacks, has particularly improved absorption characteristics, and at the same time exhibits improved volatility, thus having a high melting point and decomposition point without decomposition, more specifically a low evaporation temperature, the use of at least one such compound in optoelectronic components, and an optoelectronic component containing at least one such compound. [Means for Solving the Problems]

[0015] This object is achieved by the subject matter of the independent claims. Advantageous configurations are apparent from the dependent claims.

[0016] This object is more specifically achieved by a compound of general formula I. [Chemical Formula] (In the formula, X1 and X2 are, independently of each other, O, S, or N-R8, where R8 is selected from the group consisting of H, alkyl, aryl, and heteroaryl, preferably R8 is selected from the group consisting of H, alkyl, and aryl. R1 is a substituted homocyclic 6-membered ring, at least one H atom therein is substituted by an electron-withdrawing substituent selected from the group consisting of F, Cl, CN, CF3, and COR8, where R8 is C1-C4 alkyl, or a substituted or unsubstituted heterocyclic 5-membered or 6-membered ring, where the heterocyclic 5-membered or 6-membered ring has at least one sp2 hybridized N atom with a lone pair of electrons and / or at least one heteroatom selected from O, S, or N, and at least one H atom is substituted by an electron-withdrawing substituent selected from the group consisting of F, Cl, CN, CF3, and COR9, where R9 is C1-C4 alkyl. R2 and R7 are, independently of each other, selected from the group consisting of H, halogen, CN, alkyl, fluorinated or partially fluorinated alkyl, unsaturated alkyl, and aryl. R4 and R5 are, independently of each other, selected from the group consisting of H, halogen, CN, alkyl, fluorinated or partially fluorinated alkyl, unsaturated alkyl, and alkoxy. R3 and R6 are, independently of each other, a substituted or unsubstituted homocyclic 6-membered ring or a substituted or unsubstituted heterocyclic 5-membered or 6-membered ring.

[0017] According to the present invention, the compound of general formula I is a BODIPY dye, preferably having a 5-membered or 6-membered heteroaryl ring, or a 6-membered aryl ring having at least one substituent selected from the groups Cl, CN, and F, at the meso position of the BODIPY skeleton. The pyrrole ring of the BODIPY skeleton is preferably condensed with an additional ring system.

[0018] Substitution is particularly understood as the substitution of H by a substituent. The substituent refers to all atoms and atomic groups other than hydrogen, and preferably refers to a halogen, an alkyl group (the alkyl group may be straight-chain or branched), an alkenyl group, an alkynyl group, an amino group, an alkoxy group, a thioalkoxy group, an aryl group, or a heteroaryl group. The halogen particularly refers to F, Cl, or Br, preferably F.

[0019] Heteroatoms, particularly the heteroatoms in general formula I, refer to atoms particularly selected from the group consisting of O, S, Se, Si, B, N, or P, preferably atoms selected from the group consisting of O, S, Se, or N.

[0020] The compounds of general formula I of the present invention have advantages compared to the prior art. Advantageously, this can provide an improved absorber for optoelectronic components. Advantageously, an absorber material for the red and near-infrared spectral ranges is provided, which has a high absorption intensity and particularly good volatility. The compounds of general formula I advantageously absorb red light and near-infrared light in the wavelength range of 600 to 1000 nm. Advantageously, the fill factor FF is particularly high. Advantageously, the compounds of the present invention are suitable for vacuum processing to form optoelectronic devices. Advantageously, the volatility, particularly the volatility without decomposition, is increased, and the compounds are thermally stable at temperatures above 300 °C. As a result, the compounds can be processed under vacuum without decomposition. Surprisingly, it has been found that when using at least partially fluorinated aryl substituents instead of at least partially fluorinated alkyl chains, the achievable melting point and decomposition point are significantly increased, while the evaporation temperature only rises relatively slightly. Advantageously, the color variability of organic optoelectronic devices can be increased. Advantageously, the absorption of light in the visible range below 650 nm is relatively small, so the compounds of the present invention are very suitable for the manufacture of semi-transparent or transparent organic solar cells or photodetectors.

[0021] According to one development form of the present invention, X1 and X2 are S, or X1 and X2 are O, and / or at least one H atom in the homocyclic 6-membered ring and / or the heterocyclic 5-membered ring or 6-membered ring R1 is substituted by F or CF3, preferably by F. Thereby, the advantageous effects of the present invention are realized in a specific manner.

[0022] In a preferred embodiment of the present invention, R3 and / or R6 is a homocyclic 6-membered ring in which at least one H atom is substituted by an alkyl group, an alkoxy group, and / or an F atom.

[0023] According to one development form of the present invention, R3 and R4 and / or R5 and R6 each together form a heterocyclic 5-membered ring or 6-membered ring having at least one heteroatom selected from O, S, or N, preferably O or S, and preferably these heterocyclic 5-membered rings or 6-membered rings are unsubstituted or form a homocyclic 6-membered ring. Thereby, the advantageous effects of the present invention are realized in a specific manner.

[0024] In a preferred embodiment of the present invention, R3 and R4 and / or R5 and R6 do not form a heterocyclic 5-membered ring or 6-membered ring together in each case.

[0025] In a preferred embodiment of the present invention, X1 and R6, preferably R8 and R6, and / or X2 and R3, preferably R8 and R3, together form a heterocyclic 5-membered ring or 6-membered ring having at least one heteroatom selected from the group consisting of S, O, and N, or form a homocyclic 6-membered ring, preferably a heterocyclic 5-membered ring.

[0026] In a preferred embodiment of the present invention, X1 and R7, preferably R8 and R7, and / or X2 and R2, preferably R8 and R2, together form a heterocyclic 5-membered ring or 6-membered ring having at least one heteroatom selected from the group consisting of S, O, and N, or form a homocyclic 6-membered ring, preferably a heterocyclic 5-membered ring.

[0027] According to one development form of the present invention, R1 is a homocyclic 6-membered ring on the condition that R1 is C6HnF5-n (where n = 0, 1, 2, 3, 4). Thereby, the advantageous effects of the present invention are realized in a specific manner.

[0028] According to one development form of the present invention, R1 is selected from the group consisting of:

Chemical formula

Chemical formula

[0029] According to one development form of the present invention, R3 and R6 are independently selected from the group consisting of:

Chemical formula

Chemical formula

[0030] In a preferred embodiment of the present invention, Z is independently selected from the group consisting of halogen (preferably F), CF3, and CN in each occurrence, and particularly preferably Z is F. In an alternative preferred embodiment of the present invention, Z is methyl, methoxy, ethyl, or ethoxy.

[0031] In a preferred embodiment of the present invention, R3 and R6 are independently of each other

Chemical formula

[0032] In a preferred embodiment of the present invention, the H atoms in Y3 and / or Y4 are at least partially substituted by alkyl, alkoxy, or F.

[0033] In a preferred embodiment, the positions Y3 and Y4 are CH in each case.

[0034] In a preferred embodiment of the present invention, the R3 group is the same as the R6 group.

[0035] In a preferred embodiment of the present invention, X1 is the same as X2, R2 is the same as R7, R4 is the same as R5, and R3 is the same as R6.

[0036] In a preferred embodiment of the present invention, X1 and X2 are O or S, R2 and R7 are H, R4 and R5 are H, and R3 is the same as R6.

[0037] According to a development of the present invention, R3 and / or R6 are further fused, and / or R1 is a monocyclic 5-membered or 6-membered ring.

[0038] In a preferred embodiment of the present invention, R3 and / or R6 are fused to at least one additional 5-membered or 6-membered ring, preferably two additional 5-membered and / or 6-membered rings, where at least one of the at least one 5-membered ring and / or at least one 6-membered ring is a substituted or unsubstituted aryl or heteroaryl ring.

[0039] In another preferred embodiment of the present invention, R3 and / or R6 are not additionally fused.

[0040] According to a development of the present invention, R2 and R7 are independently selected from the group consisting of H, halogen, CN, and C1-C4 alkyl, preferably R2 and R7 are H, and / or R4 and R5 are independently selected from the group consisting of H, halogen, CN, and C1-C4 alkyl, preferably R4 and R5 are H.

[0041] According to one development form of the present invention, R1 is a heterocyclic 5-membered or 6-membered ring having at least one sp2 hybridized N atom with a lone pair of electrons in the ring system. Preferably, R1 is selected from the group consisting of substituted or unsubstituted imidazole, pyrazole, triazole, tetrazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, oxazole, isoxazole, thiazole, and isothiazole.

[0042] In a particularly preferred embodiment of the present invention, R1 is not a substituted and / or unsubstituted thiophene, preferably not an unsubstituted thiophene.

[0043] In a particularly preferred embodiment of the present invention, R1 is not a substituted and / or unsubstituted furan, preferably not an unsubstituted furan.

[0044] In a particularly preferred embodiment of the present invention, R1 is not a substituted and / or unsubstituted pyrrole, preferably not an unsubstituted pyrrole.

[0045] In a preferred embodiment of the present invention, the heterocyclic 5-membered or 6-membered ring, or the homocyclic 6-membered ring, is not additionally condensed.

[0046] According to one development form of the present invention, the compound is selected from the group consisting of the following. [Chemical formula] [Chemical formula] [Chemical formula] [Chemical formula] [Chemical formula] [Chemical formula] [Chemistry] [Chemistry]

[0047] According to one development form of the present invention, all of the H atoms in R1 are substituted by halogen, CF3, or CN, and preferably all of the H atoms are substituted by F.

[0048] The compounds of the present invention relate in particular to so-called small molecules. A small molecule is understood in particular to mean a non-polymeric organic molecule having a monodisperse molar mass of 100 to 2000 g / mol that exists in the solid phase at atmospheric pressure (the atmospheric pressure of the ambient atmosphere) and room temperature. In particular, small molecules have photoactivity, and photoactivity is understood to mean that when light is introduced, the molecule changes its charge state and / or polarization state. Molecules having photoactivity exhibit absorption of electromagnetic radiation, i.e., photons are converted into excitons, in a specific wavelength range of the absorbed electromagnetic radiation.

[0049] According to one development form of the present invention, the compound has a molar weight of 300 to 1500 g / mol.

[0050] In a preferred embodiment of the present invention, the compound of the present invention does not have a ring structure between R3 and R4 and / or between R5 and R6.

[0051] In a preferred embodiment of the present invention, the compound has a structure that is mirror-symmetric with respect to the axis passing through R1 and B.

[0052] The object of the present invention is also achieved more specifically by providing the use of at least one compound of the present invention in optoelectronic components according to one of the exemplary embodiments described above. In this case, for the use of at least one compound in optoelectronic components, in particular, the advantages already described in connection with the compounds of the present invention are brought about.

[0053] According to one development form of the present invention, the compounds of the present invention are used in organic optoelectronic components, preferably organic solar cells, OLEDs, OFETs, or organic photodetectors.

[0054] In a preferred embodiment of the present invention, at least one compound of the present invention is used as an absorber material in the photoactive layer of an optoelectronic component. In a preferred embodiment of the present invention, the compounds of the present invention are used as donors in donor-acceptor heterojunctions.

[0055] The object of the present invention is also achieved by providing an optoelectronic component having a layer system, more specifically an optoelectronic component according to one of the exemplary embodiments described above, wherein at least one layer of the layer system contains the compound of the present invention. In this case, at least one layer of the layer system contains at least one compound of the present invention. In this case, the advantages already described with respect to the compounds of the present invention and with respect to the use of at least one compound of the present invention in optoelectronic components are obtained in the optoelectronic components. The optoelectronic component includes a first electrode, a second electrode, and a layer system, and the layer system is disposed between the first electrode and the second electrode.

[0056] According to one development form of the present invention, the optoelectronic component is an organic optoelectronic component, preferably an organic solar cell, an OFET, an OLED, or an organic photodetector.

[0057] According to one development form of the present invention, the optoelectronic component includes a layer system having at least one photoactive layer, preferably a light-absorbing photoactive layer, and at least one photoactive layer contains at least one compound of the present invention.

[0058] In a preferred embodiment of the present invention, at least one photoactive layer is an absorber layer, and preferably, at least one compound is an absorber material.

[0059] In a preferred embodiment of the present invention, the photoactive layer is disposed between the first electrode and the second electrode.

[0060] In a preferred embodiment of the present invention, the layer system has at least two photoactive layers, preferably at least three photoactive layers, or preferably at least four photoactive layers.

[0061] The organic optoelectronic component is understood to particularly mean a photovoltaic device having at least one organic photoactive layer, and the organic photoactive layer contains at least one compound of the present invention. The organic photovoltaic device utilizes the photovoltaic effect to enable the conversion of electromagnetic radiation, particularly in the wavelength range of visible light, into an electric current. In this sense, the term "photoactive" is understood to mean the conversion of light energy into electrical energy. In contrast to inorganic solar cells, in an organic photovoltaic device, light does not directly generate free charge carriers. Instead, excitons, which are electrically neutral excited states (bound electron-hole pairs), are first formed. Only in a second step are these excitons separated within the free charge carriers of the photoactive donor-acceptor junction, which then contributes to the flow of an electric current.

[0062] In a preferred embodiment of the present invention, the photoactive layer is embodied as a mixed layer composed of at least one compound of the present invention and at least one additional compound, or as a mixed layer of at least one compound of the present invention and at least two additional compounds, and the compounds are preferably absorber materials.

[0063] In a preferred embodiment of the present invention, the layer system of the optoelectronic component has at least one transport layer, and at least one transport layer is doped, partially doped, or undoped. The transport layer particularly means a layer of the layer system that transports one type of charge carrier and preferably absorbs electromagnetic radiation only in the range of <450 nm to a large extent.

[0064] In a preferred embodiment of the present invention, the optoelectronic component has a substrate, and the first electrode or the second electrode is disposed on the substrate. More specifically, one of the electrodes of the optoelectronic component can be directly provided on the substrate with the layer system disposed between the first electrode and the second electrode.

[0065] In a preferred embodiment of the present invention, the layer having the compound and / or at least one compound is deposited by vacuum treatment, evaporation, or solvent treatment, particularly preferably by vacuum treatment.

[0066] The present invention will be further clarified in detail below with reference to the drawings.

Brief Description of the Drawings

[0067]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Mode for Carrying Out the Invention

[0068] Exemplary Embodiments Figure 1 shows a schematic cross-sectional view of an exemplary embodiment of an optoelectronic component. This optoelectronic component contains at least one compound of general formula I.

[0069] The optoelectronic component of the present invention has a layer system 7, and at least one layer of the layer system 7 contains the compound of the present invention.

[0070] In one configuration of the present invention, the optoelectronic component is an organic optoelectronic component, preferably an organic solar cell, OFET, OLED, or organic photodetector. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0071] The optoelectronic component includes a first electrode 2, a second electrode 6, and a layer system 7, and the layer system 7 is disposed between the first electrode 2 and the second electrode 6. At least one layer of the layer system 7 here contains at least one compound of the present invention.

[0072] In a further configuration of the present invention, the optoelectronic component has a layer system 7 having at least one photoactive layer 4, preferably a light-absorbing photoactive layer 4, and at least one photoactive layer 4 contains at least one compound of the present invention.

[0073] In a further configuration of the present invention, the layer system 7 has at least two photoactive layers 4, preferably at least three photoactive layers 4, or preferably at least four photoactive layers 4.

[0074] In an exemplary embodiment, the organic solar cell has a substrate 1, for example composed of glass, on which an electrode 2 containing, for example, ITO is disposed. On top of that, a layer system 7 containing an electron transport layer 3 (ETL) and a photoactive layer 4 is disposed. The photoactive layer 4 is in the form of either a flat heterojunction or a bulk heterojunction and has at least one compound of the present invention, a p-conductive donor material, and an n-conductive acceptor material such as C60 fullerene. On top of this, a p-doped hole transport layer 5 (HTL) and an electrode 6 of gold or aluminum are disposed, which is embodied as a bulk heterojunction.

[0075] In a further configuration of the present invention, the photoactive layer 4 is embodied as a mixed layer composed of at least one compound of the present invention and at least one additional compound, or as a mixed layer of at least one compound of the present invention and at least two additional compounds, and these compounds are absorber materials.

[0076] In a further configuration of the present invention, the optoelectronic component is embodied as a tandem cell, a triple cell, or a multi-cell. In these cases, there are two or more photoactive layers 4 stacked on top of each other, and the photoactive layers 4 are composed of the same material, different materials, or material mixtures.

[0077] The individual components of the present invention can be manufactured by vacuum evaporation with or without a carrier gas, or by treatment of a solution or suspension, such as in the case of coating or printing. The individual layers can also be provided by sputtering. This can particularly be a base contact. The production of the layers by vacuum evaporation is advantageous, and in this case, the carrier substrate may be heated.

[0078] In a further configuration of the present invention, the optoelectronic component is a flexible optoelectronic component. A flexible optoelectronic component in the sense of the present invention refers to a component that can be partially deformed when subjected to an external force. As a result, such a flexible component is suitable for placement on a curved surface.

[0079] The general preparation of the compounds of the present invention is known to those skilled in the art from the prior art. In this regard, reference is more specifically made to International Patent Application Publication No. WO 2007 / 126052 A1 pamphlet and European Patent Application No. EP 3617214 A1 specification.

[0080] The compounds of general formula I have the following structure:

Chemical formula

[0081] In one configuration of the present invention, X1 and X2 are S or X1 and X2 are O, and / or at least one H atom in the homocyclic 6-membered ring and / or heterocyclic 5-membered or 6-membered ring R1 is substituted by F or CF3, preferably by F.

[0082] In a further configuration of the present invention, R3 and R4 and / or R5 and R6 each together form a heterocyclic 5-membered or 6-membered ring having at least one heteroatom selected from O, S, or N, preferably O or S, and preferably these heterocyclic 5-membered or 6-membered rings are unsubstituted or form a homocyclic 6-membered ring.

[0083] In a further configuration of the present invention, R1 is a homocyclic 6-membered ring on the condition that R1 is C6HnF5-n (where n = 0, 1, 2, 3, 4).

[0084] In a further configuration of the present invention, R1 is selected from the group consisting of:

Chemical formula

[0085] In a further configuration of the present invention, R3 and R6 are independently selected from the group consisting of:

Chemical formula

Chemical formula

[0086] In a further configuration of the present invention, R3 and / or R6 are further condensed, and / or R1 is a monocyclic 5-membered or 6-membered ring.

[0087] In a further configuration of the present invention, R2 and R7 are independently selected from the group consisting of H, halogen, CN, and C1-C4 alkyl, preferably, R2 and R7 are H, and / or R4 and R5 are independently selected from the group consisting of H, halogen, CN, and C1-C4 alkyl, preferably R4 and R5 are H.

[0088] In a further configuration of the present invention, R1 is a heterocyclic 5-membered or 6-membered ring having at least one sp2 hybridized N atom with a lone pair in the ring system, preferably, R1 is selected from the group consisting of substituted or unsubstituted imidazole, pyrazole, triazole, tetrazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, oxazole, isoxazole, thiazole, and isothiazole.

[0089] In a further configuration of the present invention, the compound is selected from the group consisting of:

Chemical formula

Chemical formula

Chemical formula

[0090] In a further configuration of the present invention, all of the H atoms in R1 are substituted by halogen or CN, and preferably all of the H atoms are substituted by F.

[0091] In a further configuration of the present invention, the compound has a molar weight of 300 to 1500 g / mol.

[0092] In one configuration of the present invention, the compound of the present invention is used in optoelectronic components, preferably organic optoelectronic components, particularly preferably organic solar cells, OLEDs, OFETs, or organic photodetectors.

[0093] In the following Figures 2 to 21, specific exemplary embodiments of the compound of the present invention having the general formula I and its optical properties are shown. The parameters of the open-circuit voltage Uoc, short-circuit current Jsc, and fill factor FF are based on the same configuration of the photovoltaic device, respectively.

[0094] Figure 2 shows a graphical representation of the absorption spectrum of compound (1).

[0095] The absorption spectra (optical density versus wavelength (nm)) of compounds (1) to (32) were measured for layers with a thickness of 30 nm provided by vacuum evaporation on fused silica and in dichloromethane solution in each case.

[0096] Figure 3 shows a graphical representation of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (1) measured in an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0097] The current-voltage curve contains quantities that characterize the organic solar cell. The most important quantities here are the fill factor FF, the open-circuit voltage Uoc, and the short-circuit current Jsc.

[0098] To investigate the compound, i.e., for its use as absorber material in organic optoelectronic components, the current-voltage curve of the BHJ cell was measured. In this exemplary embodiment, the BHJ cell on the ITO layer has a layer of C60 with a layer thickness of 15 nm. To this layer, the compound (1) was applied with C60 at a thickness of 30 nm. The layer following this layer is a layer of BPAPF (9,9-bis[4-(N,N-bis(biphenyl-4-ylamino)-phenyl]-9H-fluorene) with a layer thickness of 10 nm. Above this, another layer containing BPAPF and NDP9 with a layer thickness of 45 nm is located. Adjacent to this layer is another layer containing NDP9 with a thickness of 1 nm, followed by a layer of gold with a thickness of 50 nm. In this configuration, ITO functions as electrode 2, the adjacent fullerene C60 functions as electron transport layer (ETL) 3, followed by a photoactive layer 4 containing C60 as electron acceptor material and each absorber, followed by BPAPF (9,9-bis[4-(N,N-bis(biphenyl-4-ylamino)phenyl]-9H-fluorene) as hole transport layer (HTL) 5, and BPAPF doped with NDP9 (Novaled AG), followed by gold electrode 6. According to the invention, at least one layer in the semiconductor component / layer system contains a compound of general formula I.

[0099] The current-voltage curve of a BHJ cell having the following configuration: ITO / C60(15 nm) / compound(1):C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm) was determined. The cell parameters were measured under AM1.5 illumination (AM = air mass; AM = 1.5, in this spectrum the total radiant power is 1000 W / m2; AM = 1.5 is the standard value for the measurement of solar cell modules). The photoactive layer contained a bulk heterojunction (BHJ).

[0100] In the optoelectronic component containing compound (I), the fill factor FF is 69.7%, the open-circuit voltage Uoc is 0.71 V, and the short-circuit current Jsc is 10.2 mA / cm2. For this type of optoelectronic component using compound (1), more specifically, the cell efficiency of the solar cell is 5.05%.

[0101] Compound (1) shows good evaporability under vacuum. The evaporation temperature of compound (1) is 230 °C, and the decomposition temperature is 377 °C. In comparison, the corresponding comparative compound (1) having a CF3 group instead of a C6F5 group at the meso position of compound (1) has an evaporation temperature of 215 °C, and the decomposition temperature is only 317 °C, which is 60 °C lower.

[0102] Figure 4 shows a graphical representation of the absorption spectrum of compound (3).

[0103] Figure 5 shows a graphical representation of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (3) measured in an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0104] The current-voltage curve of a BHJ cell having the following configuration: ITO / C60 (15 nm) / compound (3):C60 (30 nm, 3:2, 90 °C) / BPAPF (10 nm) / BPAPF:NDP9 (45 nm, 10 wt% NDP9) / NDP9 (1 nm) / Au (50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing compound (3), the fill factor FF is 73.4%, the open-circuit voltage Uoc is 0.69 V, and the short-circuit current Jsc is 11.4 mA / cm2. For this type of optoelectronic component using compound (3), more specifically, the cell efficiency of the solar cell is 5.77%.

[0105] Compound (3) shows good evaporability under vacuum.

[0106] Figure 6 shows a graphical representation of the absorption spectrum of compound (5).

[0107] Figure 7 shows a graphical representation of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (5) measured with an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0108] The current-voltage curve of a BHJ cell having the following configuration: ITO / C60(15 nm) / Compound (5):C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing compound (5), the fill factor FF was 71.7%, the open-circuit voltage Uoc was 0.95 V, and the short-circuit current Jsc was 9.4 mA / cm2. The cell efficiency of this type of optoelectronic component using compound (5), more specifically a solar cell, was 6.40%.

[0109] Figure 8 shows a graphical representation of the absorption spectrum of compound (8).

[0110] Figure 9 shows a graphical representation of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (8) measured with an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0111] The current-voltage curve of a BHJ cell having the following configuration: ITO / C60(15 nm) / Compound (8):C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing compound (8), the fill factor FF was 70.4%, the open-circuit voltage Uoc was 0.72 V, and the short-circuit current Jsc was 11.0 mA / cm2. The cell efficiency of this type of optoelectronic component using compound (8), more specifically a solar cell, was 5.58%.

[0112] Figure 10 shows a graphical representation of the absorption spectrum of compound (10).

[0113] Figure 11 shows graphical representations of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (10) measured with an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0114] The current-voltage curve of a BHJ cell having the following configuration: ITO / C60 (15 nm) / compound (10):C60 (30 nm, 3:2, 90 °C) / BPAPF (10 nm) / BPAPF:NDP9 (45 nm, 10 wt% NDP9) / NDP9 (1 nm) / Au (50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing compound (10), the fill factor FF was 67.6%, the open-circuit voltage Uoc was 0.90 V, and the short-circuit current Jsc was 9.6 mA / cm2. The cell efficiency of this type of optoelectronic component using compound (10), more specifically a solar cell, was 5.84%.

[0115] Figure 12 shows a graphical representation of the absorption spectrum of compound (14).

[0116] Figure 13 shows graphical representations of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (14) measured with an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0117] The current-voltage curve of a BHJ cell having the following structure: ITO / C60(15 nm) / Compound(14):C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing Compound(14), the fill factor FF was 65.0%, the open-circuit voltage Uoc was 0.91 V, and the short-circuit current Jsc was 10.2 mA / cm2. The cell efficiency of this type of optoelectronic component using Compound(14), more specifically a solar cell, was 6.03%.

[0118] Figure 14 shows a graphical representation of the absorption spectrum of Compound(15).

[0119] Figure 15 shows a graphical representation of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing Compound(15) measured in an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0120] The current-voltage curve of a BHJ cell having the following structure: ITO / C60(15 nm) / Compound(15):C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing Compound(15), the fill factor FF was 67.7%, the open-circuit voltage Uoc was 0.95 V, and the short-circuit current Jsc was 9.7 mA / cm2. The cell efficiency of this type of optoelectronic component using Compound(15), more specifically a solar cell, was 6.24%.

[0121] Figure 16 shows a graphical representation of the absorption spectrum of Compound(29).

[0122] Figure 17 shows a graphical representation of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (29) measured in an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0123] The current-voltage curve of a BHJ cell having the following configuration: ITO / C60(15 nm) / Compound (29):C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing compound (29), the fill factor FF was 64.0%, the open-circuit voltage Uoc was 0.68 V, and the short-circuit current Jsc was 12.6 mA / cm2. The cell efficiency of this type of optoelectronic component using compound (29), more specifically a solar cell, was 5.48%.

[0124] Figure 18 shows a graphical representation of the absorption spectrum of compound (32).

[0125] Figure 19 shows a graphical representation of the current-voltage curve, spectral external quantum efficiency, and fill factor of a BHJ cell containing compound (32) measured in an organic optoelectronic component. In this exemplary embodiment, the optoelectronic component is an organic solar cell.

[0126] The current-voltage curve of a BHJ cell having the following configuration: ITO / C60(15 nm) / Compound (32):C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm) was determined. The photoactive layer 4 included a bulk heterojunction (BHJ). In the optoelectronic component containing compound (32), the fill factor FF was 69.9%, the open-circuit voltage Uoc was 1.0 V, and the short-circuit current Jsc was 9.4 mA / cm2. The cell efficiency of this type of optoelectronic component using compound (32), more specifically a solar cell, was 6.57%.

[0127] The advantageous properties of the compounds of the present invention are also evident in the parameters of the open-circuit voltage Uoc, short-circuit current Jsc, and fill factor FF for the same structure of the solar cell. The compounds of the present invention have not only improved absorption properties but also appropriate charge transport properties. From the experimental data including the absorption properties of compounds (1), (3), (5), (8), (10), (14), (15), (29), and (32) and the current-voltage profiles measured in organic solar cells, it is shown that these compounds are very suitable for use in organic solar cells and other organic optoelectronic components.

[0128] Table 1 shows the absorption maxima of compounds (1) to (32) in solution and in the film.

[0129]

Table 1

[0130]

Table 2

[0131]

Table 3

[0132]

Table 4

[0133]

Table 5

[0134]

Table 6

[0135]

Table 7

[0136]

Table 8

[0137]

Table 9

[0138]

Table 10

[0139]

Table 11

[0140]

Table 12

[0141] The optical properties were determined experimentally. The absorption maximum λmax was determined using a photometer from a vacuum-deposited layer with a thickness of 30 nm on fused silica in a cuvette containing dichloromethane. Surprisingly, it was found that the compounds (1) - (32) in the film exhibit particularly broad absorption in the near-infrared range beyond 650 nm, which is no longer visible to the human eye. Furthermore, it could be shown that the compounds (1) - (32) have high thermal stability and can be evaporated under vacuum without decomposition. Additionally, the melting temperature DSC is shown in Table 1.

[0142] Table 2 shows the photovoltaic parameters of Voc, Jsc, and FF parameters of the compounds (1) to (32) of the present invention compared directly. The cell configuration is glass equipped with ITO / C60(15 nm) / absorber: C60(30 nm, 3:2, 90 °C) / BPAPF(10 nm) / BPAPF:NDP9(45 nm, 10 wt% NDP9) / NDP9(1 nm) / Au(50 nm), and the measurement is performed under AM1.5 illumination (AM = air mass; AM = 1.5. In this spectrum, the total radiant power is 1000 W / m2, and AM = 1.5 is the standard value for the measurement of solar cell modules).

[0143]

Table 13

[0144] The experimental data on the compounds of the present invention, including the absorption characteristics of the compounds and the current-voltage profiles measured in organic solar cells, indicate that the compounds of the present invention are very suitable for use in organic solar cells and other organic optoelectronic components.

Claims

1. A compound of general formula I: 【Chemical 23】 (wherein, X １ and X ２ are, independently of one another, O, S, or N—R ８ wherein R ８ is selected from the group consisting of H, alkyl, aryl, and heteroaryl R １ is a substituted homoaromatic 6-membered ring, and at least one H atom therein is substituted by an electron-withdrawing substituent selected from the group consisting of F, Cl, CN, and CF ３ or is a substituted or unsubstituted heteroaromatic 5-membered or 6-membered ring, and the heteroaromatic 5-membered or 6-membered ring has at least one sp ２ hybridized N atom having a lone pair of electrons and / or at least one heteroatom selected from O, S, or N, and in the substituted heteroaromatic 5-membered or 6-membered ring, at least one H atom is substituted by an electron-withdrawing substituent selected from the group consisting of F, Cl, CN, and CF ３ and R ２ and R ７ are each independently selected from the group consisting of H, alkyl, and unsaturated alkyl, R ４ and R ５ are each independently selected from the group consisting of H, alkyl, and unsaturated alkyl, R ３ and R ６ are each, independently of one another, a substituted or unsubstituted homocyclic 6-membered ring or a substituted or unsubstituted heterocyclic 5-membered or 6-membered ring).

2. X １ and X ２ is S, or X １ and X ２ is O, and / or at least one H atom in said homocyclic 6-membered ring and / or said heterocyclic 5-membered or 6-membered ring R １ is substituted by F, the compound according to claim 1.

3. R ４ and R ５ is H, and / or R ２ and R ７ is H, the compound according to claim 1 or 2.

4. R １ is C ６ H ｎ F ５－ｎ under the condition that (n = 0, 1, 2, 3, 4), R １ is a homoaromatic 6-membered ring, the compound according to any one of claims 1 to 3.

5. R １ The compound according to any one of claims 1 to 4, wherein R is selected from the group consisting of the following: 【Chemical 24】 【Chemical 25】 (In these formulas, * represents a bond to the compound of the general formula I, and Y is independently in each occurrence selected from the group consisting of Cl, CN, F, and CF ３ and the H atom is substituted or unsubstituted).

6. R ３ and R ６ are each independently selected from the group consisting of the compound according to any one of claims 1 to 5 【Chemical 26】 【Chemical 27】 【Chemical Formula 28】 (In these formulas, * represents a bond to the compound of the general formula I, U is selected from the group consisting of O, S, and NR １９ selected from the group consisting of, R １９ is selected from the group consisting of H, halogen, alkyl, fluorinated alkyl, partially fluorinated alkyl, alkoxy, alkenyl, aryl, and heteroaryl, and Z is, independently in each occurrence, H, halogen, CF ３ , CN, alkyl, fluorinated alkyl, partially fluorinated alkyl, alkenyl, alkoxy, N-alkyl, N-alkyl2, aryl, and heteroaryl).

7. Z is F, and / or R ３ and R ６ is the same as that of the compound according to claim 6.

8. R １ is a heteroaromatic 5-membered or 6-membered ring having at least one sp ２ hybridized N atom with a lone pair of electrons in the ring system, the compound according to any one of claims 1 to 7.

9. The compound according to any one of claims 1 to 8, selected from the group consisting of: 【Chemical 29】 【Chemical Formula 30】 【Chemical Formula 31】 【Chemical 32】 。

10. R １ The compound according to any one of claims 1 to 9, wherein all of the H atoms therein are substituted by halogen or CN.

11. The compound according to any one of claims 1 to 10, having a molar weight of 300 to 1500 g / mol.

12. An optoelectronic component having a layer system, wherein at least one layer of the layer system contains the compound according to any one of claims 1 to 11.

13. The optoelectronic component according to claim 12, wherein the optoelectronic component is an organic solar cell, an OFET, an OLED, or an organic photodetector.

14. The optoelectronic component according to claim 12 or 13, comprising a layer system having at least one photoactive layer, wherein the at least one photoactive layer contains the compound according to any one of claims 1 to 11.

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