Optoelectronic component with a photoactive layer designed as a planar heterojunction

Abstract

The invention relates to optoelectronic component, comprising a bottom electrode (2), a top electrode (6), and a layer system (7) with at least one photoactive layer (4). The layer system is arranged between the bottom electrode and the top electrode, and at least one photoactive layer is designed as a planar heterojunction (PHJ), wherein the at least one photoactive layer designed as a planar heterojunction has at least one chemical compound of the general formula I. The invention also relates to the use of such a compound of the general formula I in an optoelectronic component and to a chemical compound of the general formula II.

Description

[0001] Optoelectronic component with a photoactive layer formed as a planar heterojunction

[0002] The present invention relates to an optoelectronic component having at least one photoactive layer formed as a planar heterojunction (PHJ), wherein the at least one photoactive layer comprises a chemical compound of the general formula I, and to the use of such a compound of the general formula I in an optoelectronic component.

[0003] Optoelectronic components can be displays, data storage devices or transistors, but also photovoltaic elements, in particular solar cells, and photodetectors, which have a photoactive layer in which electron-hole pairs (excitons) are generated when electromagnetic radiation hits them. The excitons reach such an interface by diffusion, where electrons and holes are separated from each other. The material that takes up the electrons is called the acceptor and the material that takes up the holes is called the donor. Organic optoelectronic components enable the conversion of electromagnetic radiation into electrical current by utilising the photoelectric effect. For this type of conversion of electromagnetic radiation, absorber materials with good absorption properties are required.

[0004] Organic optoelectronic components are known from the state of the art.

[0005] W02004083958A2 discloses a photoactive component, in particular a solar cell, consisting of organic layers of one or more pi, ni and / or pin diodes stacked on top of one another.

[0006] W02011161108A1 discloses a structure of an organic solar cell as a pin or nip diode. A pin solar cell consists of a substrate with a mostly transparent electrode arranged thereon, p-layer(s), i-layer(s), n-layer(s) and a counter electrode. Here, n or p means n- or p-doping, which leads to an increase in the density of free electrons or holes in the thermal equilibrium state. Such layers are primarily to be understood as transport layers. The term i-layer refers to an undoped layer (intrinsic layer) with an absorber material or a mixture of several absorber materials (planar heterojunction). One or more i-layers can consist of a mixture of two or more materials (bulk heterojunctions), at least one donor and at least one acceptor.An absorber material, i.e., an absorber, is understood in particular to be a compound that absorbs light in a specific wavelength range. Accordingly, an absorber layer is understood in particular to be a layer in an optoelectronic component that comprises at least one absorber material.

[0007] Numerous polymeric and non-polymeric absorber materials for organic photovoltaic elements in the red and near-infrared (NIR) range between approximately 600 and approximately 1400 nm are known from the state of the art. Among non-polymeric absorber materials, materials from the BODIPY class have proven particularly suitable for the near-infrared spectral range, allowing suitable energy levels and thus high photovoltages to be achieved while simultaneously maintaining long-wavelength absorption ranges.

[0008] EP 3 014 674 A1 discloses an organic electronics component which comprises at least one organic layer between two electrodes, wherein the organic layer comprises at least one compound from the group of BODIPYs.

[0009] Bartelmess et al. (“meso-Pyridyl BODIPYs with tunable chemical, optical and electrochemical properties”, New Journal of Chemistry, 2013, 37(9), 2663-2668) discloses the synthesis of meso-pyridyl substituted BODIPY compounds and their optical and electrochemical properties. The absorbers known from the state of the art cannot be used in planar heterojunctions of electronic components with an efficiency sufficient for commercial application. The known absorber materials show in particular a low efficiency. The efficiency of an organic photovoltaic element depends, among other things, on the absorption behavior of the organic materials, i.e. the absorber materials, in the photoactive layer.Although the known absorber materials are suitable for photoactive layers in organic photovoltaic elements, i.e. organic solar cells, the absorption properties of the absorber materials need to be improved.

[0010] A disadvantage, however, is that planar heterojunctions (PHJs) are not well suited for use in electronic components, especially photovoltaic elements, because the efficiency of the photovoltaic elements was severely limited, possibly due to a limited exciton diffusion length in such layers. PHJ cells have therefore not been considered for industrial use in photovoltaic elements to date.

[0011] However, it would be desirable to use PHJs in photovoltaic elements as this would improve their efficiency and simplify production. There is a need for absorber materials which have high absorption, particularly in the red and near-infrared spectral range, and thus lead to high efficiency in a PHJ. In a BHJ, each component must form microdomains which are connected to one another in closed percolation paths, otherwise no charge transport can take place. The size of the individual microdomains is particularly relevant, with excessively large individual domains leading to a loss of photocurrent. Optimal process parameters for their production are difficult to achieve, so that the technically achievable efficiency of a BHJ falls short of what is possible under idealized laboratory conditions.A PHJ, on the other hand, has much lower requirements for process parameters, since the morphology of single layers intrinsically has fewer degrees of freedom to be controlled compared to a BHJ.

[0012] The invention is therefore based on the object of providing an optoelectronic component with at least one photoactive layer designed as a planar heterojunction with a chemical compound of the general formula I and a use of the chemical compound of the general formula I in a photoactive layer of an optoelectronic component designed as a planar heterojunction, wherein the disadvantages mentioned do not occur and wherein in particular the use of planar heterojunctions is possible without limiting the efficiency of the photovoltaic elements.

[0013] The problem is solved by the subject matter of the independent claims. Advantageous embodiments emerge from the subclaims.

[0014] The object is achieved in particular by providing an optoelectronic component, preferably a photovoltaic element, with a base electrode, a cover electrode and a layer system with at least one photoactive layer, wherein the layer system is arranged between the base electrode and the cover electrode, wherein at least one photoactive layer is designed as a planar heterojunction (PHJ), and wherein the at least one photoactive layer designed as a planar heterojunction has at least one chemical compound of the general formula I, with Yi selected from the group consisting of N and CR21, where R21 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Y2 selected from the group consisting of N and CR22, where R22 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Y3 selected from the group consisting of N and CR23, where R23 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Z1 and Z2 independently selected from the group consisting of F, Cl, CN, CF3, C2F5, OCH3, and OC2H5; with RI and R2 independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl, CF3, CHF2, CH2F or CH3;with R3 and R5 independently of one another selected from the group consisting of H, halogen, CN, unsubstituted and aryl or heteroaryl-substituted alkyl, unsubstituted and aryl or heteroaryl-substituted alkenyl, O-alkyl, S-alkyl, a unsubstituted and alkyl-substituted heterocyclic 5-ring and 6-ring, preferably with at least one heteroatom selected from S, O and N, and a unsubstituted and alkyl-substituted homocyclic 6-ring, where the unsubstituted or substituted heterocyclic 5-ring or 6-ring, or the unsubstituted or substituted homocyclic 6-ring can be fused to another unsubstituted or substituted heterocyclic 5-ring or 6-ring;with R4 and R6 independently selected from the group consisting of H, halogen, CN, alkyl, alkenyl, O-alkyl, S-alkyl, an unsubstituted and halogen-, alkyl-, and / or O-alkyl-substituted heterocyclic 5-membered ring and 6-membered ring, preferably having at least one heteroatom selected from S, O or N, and an unsubstituted and halogen-, alkyl-, and / or O-alkyl-substituted homocyclic 6-membered ring; or wherein R3 and R4 and / or R5 and R6 each together form an unsubstituted or halogen-, alkyl-, O-alkyl-, aryl-, and / or heteroaryl-substituted heterocyclic 5-membered ring or 6-membered ring, preferably having at least one heteroatom selected from S, O and N, or an unsubstituted or halogen-, alkyl-, O-alkyl-, aryl-, and / or heteroaryl-substituted homocyclic 6-membered ring.;

[0015] Substitution is understood, in particular, to mean the replacement of H by a substituent. A substituent is understood, in particular, to mean all atoms and atom groups other than hydrogen, preferably a halogen, preferably F, Cl, or Br, particularly preferably F, an alkyl group (where the alkyl group may be linear or branched), an alkenyl group, an alkynyl group, an amino group, an alkoxy group, a thioalkoxy group, an aryl group, or a heteroaryl group.

[0016] A heteroatom, in particular a heteroatom in the general formula I, is understood to mean in particular an atom selected from the group consisting of O, S, Se, and N.

[0017] In a preferred embodiment of the invention, Y1 is selected from the group consisting of N and CR21, where R21 is H, C1-C4-alkyl, or a halogen, preferably F or Cl; Y2 is selected from the group consisting of N and CR22, where R22 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; and Y3 is selected from the group consisting of N and CR23, where R23 is H, C1-C4-alkyl, or a halogen, preferably F or Cl.

[0018] In a preferred embodiment of the invention, RI and R2 are independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-C1-C4-alkyl, S-C1-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl or CF3.

[0019] In a preferred embodiment of the invention, in the substituted alkenyl, O-alkyl, or S-alkyl in R3 and R5, one H atom is replaced by a group selected from an unsubstituted and substituted heterocyclic 5-membered ring or 6-membered ring, preferably with at least one heteroatom selected from S, O and N, and an unsubstituted and substituted homocyclic 6-membered ring.

[0020] In a preferred embodiment of the invention, in R3 and / or R5 the non-substituted or substituted heterocyclic 5-membered ring or 6-membered ring, or the non-substituted or substituted homocyclic 6-membered ring is further fused with at least one further heterocyclic 5-membered ring or 6-membered ring or with at least one homocyclic 6-membered ring, preferably with a non-substituted or substituted heterocyclic 5-membered ring having at least one heteroatom selected from S and O.

[0021] In a preferred embodiment of the invention, R3 and R4 and / or R5 and R6 each together form a non-substituted or a halogen, alkyl, O-alkyl, aryl and / or heteroaryl-substituted heterocyclic 5-membered ring or 6-membered ring, preferably with at least one heteroatom selected from S, O and N, or a non-substituted or a halogen, alkyl, O-alkyl, aryl and / or heteroaryl-substituted homocyclic 6-membered ring.

[0022] In a preferred embodiment of the invention, the non-substituted or substituted heterocyclic 5-membered ring or 6-membered ring formed between R3 and R4 and / or R5 and R6, or the non-substituted or substituted homocyclic 6-membered ring is not further fused.

[0023] In a preferred embodiment of the invention, R4 and R6 are independently selected from the group consisting of H, halogen, CN, and unsubstituted and substituted alkyl. In a particularly preferred embodiment, R4 and R6 are H.

[0024] In a preferred embodiment of the invention, R4 and R6 are the same, and / or R3 and R5 are the same.

[0025] In a preferred embodiment of the invention, ZI is equal to Z2 , R3 is equal to R5 , and R4 is equal to R6 .

[0026] An optoelectronic component is understood to mean, in particular, a photovoltaic element having at least one organic photoactive layer, the organic photoactive layer comprising at least one compound according to the invention. An organic photovoltaic element makes it possible to convert electromagnetic radiation, in particular in the wavelength range of visible light, into electrical current by utilising the photoelectric effect. 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 organic photovoltaic elements free charge carriers are not directly generated by the light, but excitons, i.e. electrically neutral excited states (bound electron-hole pairs), are first formed.Only in a second step are these excitons separated into free charge carriers in a photoactive donor-acceptor transition, which then contribute to the flow of electrical current.

[0027] The optoelectronic component according to the invention has advantages compared to the prior art. Advantageously, improved absorbers for planar heterojunctions in optoelectronic components can be provided. Due to the limited diffusion length in planar heterojunctions, which limits the efficiency of optoelectronic components based on planar heterojunctions, the use of planar heterojunctions has so far been difficult. However, the use of planar heterojunctions in optoelectronic components is desirable due to their easier producibility compared to bulk heterojunctions. Advantageously, the compounds according to the invention enable an improved EQE max(maximum external quantum yield) in optoelectronic components with planar heterojunctions. Advantageously, the compounds according to the invention enable the use of planar heterojunctions in commercial optoelectronic components, which are in particular easier to produce than bulk heterojunctions. Advantageously, absorber materials for the red and near-infrared spectral range with a high absorption strength and particularly good evaporability are also provided for planar heterojunctions, which can be processed in particular in a vacuum without decomposition. Advantageously, in particular the steric configuration of the groups in the meso position of the BODIPY basic structure leads to a preferred spatial arrangement of the compounds in the photoactive layer. The effect of an improved PHJ cell appears to result from an increased exciton diffusion length.Advantageously, the compounds according to the invention show exceptionally good properties in a planar heterojunction (PHJ), whereby in particular higher layer thicknesses and consequently higher efficiencies of solar cells are enabled.

[0028] In a preferred embodiment of the invention, Zi and Z2 are each F or CF3.

[0029] In a particularly preferred embodiment of the invention, RI and R2 are substituted by Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(C1-C4-alkyl)2, preferably with a substituent selected from the group consisting of: F, Cl, CN, CF3 and COR8 with R8 being Cl-C4-alkyl.

[0030] According to a further development of the invention, it is provided that Z1 and Z2 are F; and / or R1 and R2 are independently selected from the group consisting of H, F, Br, Cl, CN, Me, Et, OMe, SMe, OEt, SEt, Pr, and iPr, with the proviso that at least R1 or R2 is Br, Cl or CF3, wherein preferably R1 and R2 are not H; or R1 and R2 are independently selected from the group consisting of Cl, Br, CF3, CN, Me, Et, OMe, SMe, OEt, and SEt, with the proviso that at least R1 or R2 is Cl, Br, CF3 or Me; or preferably R1 and R2 are selected from the group consisting of Br, Cl, CF3, CHF2, CH2F and CH3.

[0031] In a particularly preferred embodiment of the invention, RI and R2 are independently selected from the group consisting of Cl, CN, Me, Et, OMe, SMe, OEt, and SEt, with the proviso that at least RI or R2 is Cl.

[0032] According to a further development of the invention, it is provided that Y i is selected from the group consisting of N and CR 21 , where R 21 is H or Cl, and / or Y 2 is selected from the group consisting of N and CR 22 , where R 22 is H, CH 3, O-CH 3, S-CH 3, F, Cl, CF 3 or SF 5, preferably N or CH , and / or Y 3 is selected from the group consisting of N and CR 23 , where R 23 is H or Cl ; where preferably one Y i, Y 2 , Y 3 is an N , or two Y i, Y 2 , Y 3 are an N .

[0033] In a preferred embodiment of the invention, Yi is N or CH, and / or Y2 is N, CH, or C-halogen, preferably CF or C-Cl, and / or Y3 is N and CH, where preferably at least one Yi, Y2, Y3 is an N, or at least two Yi, Y2, Y3 are an N.

[0034] In a preferred embodiment of the invention, Yi is N, Y2 is CH, and Y3 is N, or Yi is N, Y2 is C-halogen, preferably CF or C-Cl, and Y3 is N, or Y x CH, Y2N, and Y3CH, or is Y xCH, Y2CH, and Y3CH , and / or Yi is CH , Y2 is C-halogen, preferably CF or C-Cl , and Y3CH .

[0035] According to a further development of the invention, it is provided that R3 and R4 and / or R5 and R6 form a non-substituted or substituted heterocyclic 5-membered ring or 6-membered ring with at least one heteroatom selected from O, S and N, preferably from O and S, or a non-substituted or substituted homocyclic 6-membered ring, or R3 and R4 and / or wherein R5 and R6 form a non-substituted or substituted heterocyclic 5-membered ring, preferably a substituted heterocyclic 5-membered ring, with at least one heteroatom selected from O, S and N, preferably O and S, or a non-substituted or substituted homocyclic 6-membered ring, preferably a non-substituted homocyclic 6-membered ring.

[0036] In a preferred embodiment of the invention, the substituted heterocyclic 5-membered ring or 6-membered ring formed between R3 and R4 and / or R5 and R6 is preferably substituted by at least one heteroatom selected from S, O and N, selected from the group consisting of halogen, CN, alkyl, O-alkyl, S-alkyl, a non-substituted and substituted heterocyclic 5-membered ring or 6-membered ring, preferably by a heteroatom independently selected from S, O and N, and a non-substituted and substituted homocyclic 6-membered ring. In a preferred embodiment of the invention, the homocyclic 6-membered ring is not substituted.In a preferred embodiment of the invention, the substituted homocyclic 6-membered ring formed between R3 and R4 and / or R5 and R6 is substituted and selected from the group consisting of halogen, CN, alkyl, O-alkyl, S-alkyl, an unsubstituted and substituted heterocyclic 5-membered ring or 6-membered ring, preferably with a heteroatom independently selected from S, O and N, and an unsubstituted and substituted homocyclic 6-membered ring. In a preferred embodiment of the invention, the homocyclic 6-membered ring is unsubstituted.

[0037] In a preferred embodiment of the invention, R3 and R4 and / or R5 and R6 together form a non-substituted or substituted heterocyclic 5-membered ring or 6-membered ring having at least one heteroatom selected from S, O and N. In a preferred embodiment of the invention, R3 and R4 and / or R5 and R6 together form a non-substituted or substituted furanyl ring or thienyl ring.

[0038] In a preferred embodiment of the invention, the unsubstituted or substituted heterocyclic 5-membered ring or 6-membered ring formed by R3 and R4 and / or R5 and R6, or the unsubstituted or substituted homocyclic 6-membered ring is fused to a unsubstituted or substituted thienyl ring or furanyl ring.

[0039] In a preferred embodiment of the invention, R3 and R4 and / or R5 and R6 each together form a non-substituted heterocyclic 5-membered ring or 6-membered ring, preferably with at least one heteroatom selected from S, O and N.

[0040] In a preferred embodiment of the invention, R3 and R4 and / or R5 and R6 together form a non-substituted or substituted homocyclic 6-membered ring, and R3 and R4 and / or R5 and R6 together do not form a heterocyclic 5-membered ring or 6-membered ring. According to a further development of the invention, the at least one chemical compound is a compound of the general formula II, with Y1 selected from the group consisting of N and CR21, where R21 is H, alkyl, preferably C1-C4-alkyl, O-alkyl, S-alkyl, or a halogen, preferably F or Cl; with Y2 selected from the group consisting of N and CR22, where R22 is H, alkyl, preferably C1-C4-alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3; with Y3 selected from the group consisting of N and CR23, where R23 is H, alkyl, preferably C1-C4-alkyl, O-alkyl, S-alkyl, or a halogen, preferably F or Cl; with Z1 and Z2 being F or CF3; with X1 and X2 independently of one another are O, S or N-R8 with R8 selected from the group consisting of H, alkyl and aryl, where preferably X1 and X2 are S or X1 and X2 are 0; with RI and R2 independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl, CF3, CHF2, CH2F, or CH3, preferably Br or Cl;wherein R13 and R15 are independently selected from the group consisting of H, halogen, CN, alkyl, O-alkyl, and S-alkyl, preferably H or C1-C4-alkyl; wherein R14 and R16 are independently selected from the group consisting of an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted heterocyclic 5-membered ring or 6-membered ring, preferably with a heteroatom independently selected from S, O and N, and an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted homocyclic 6-membered ring, preferably an unsubstituted and substituted heterocyclic 5-membered ring, and an unsubstituted and substituted homocyclic 6-membered ring.;

[0041] In a preferred embodiment of the invention, R14 and R16 are a substituted heterocyclic 5-membered ring, wherein at least one H atom, preferably one H atom, of the heterocyclic 5-membered ring is substituted, preferably with a substituent selected from the group consisting of H, halogen, CN, alkyl, O-alkyl, and S-alkyl. In a preferred embodiment of the invention, R14 and / or R16 are not further fused.

[0042] In a preferred embodiment of the invention, R14 and R16 are independently a non-substituted or substituted furanyl ring or thienyl ring.

[0043] In a preferred embodiment of the invention, XI and X2 are S or XI and X2 are 0 , particularly preferably Xi and X2 are 0 .

[0044] In a preferred embodiment of the invention, in R14 and R16 at least one H atom of the homocyclic 6-membered ring and / or the heterocyclic 5-membered ring or 6-membered ring is substituted by F or CF3, preferably by F.

[0045] In a preferred embodiment of the invention, R13 and R15 are H.

[0046] In a preferred embodiment of the invention, R13 and R15 are the same, and / or R14 and R16 are the same.

[0047] In a preferred embodiment of the invention, ZI is Z2 , R13 is R15 , and R14 is R16 .

[0048] In a preferred embodiment of the invention, XI and X2 are equal to O or S, R13 and R15 are H, and R14 and R16 are a non-substituted or substituted heterocyclic 5-membered ring or 6-membered ring, preferably having a heteroatom selected from S, O and N, or a non-substituted or substituted homocyclic 6-membered ring, preferably a substituted heterocyclic 5-membered ring.

[0049] In a preferred embodiment of the invention, R13 and R14 and / or R15 and R16 each form a non-substituted or substituted heterocyclic 5-membered ring or 6-membered ring having at least one heteroatom selected from S, O and N, or a non-substituted or substituted homocyclic 6-membered ring.

[0050] In a preferred embodiment of the invention, R13 and R14 and / or R15 and R16 each form a non-substituted or substituted heterocyclic 5-membered ring having at least one heteroatom selected from S, O and N.

[0051] In a preferred embodiment of the invention, the compounds according to the invention have no ring structure between R13 and R14 and / or between R15 and R16.

[0052] According to a further development of the invention, it is provided that where R14 and R16 are independently selected from the group consisting of , with X3 is O, S, or N-R9 with R9 selected from the group consisting of H, alkyl and aryl; with R17 to R19 and R31 to R35 independently of one another selected from the group consisting of H, halogen, preferably F and Cl, CN, alkyl, preferably Cl-C4-alkyl, O-alkyl, preferably O-Cl-C4-alkyl, and S-alkyl, preferably S-Cl-C4-alkyl, where preferably at least one H atom in R31 to R35 is substituted by F.

[0053] In a preferred embodiment of the invention, R17 and / or R18 are H, preferably R17 and R18 . In a preferred embodiment of the invention, at least R31 and R35 are H .

[0054] In a preferred embodiment of the invention, R31, R32, R34 and R35 are H.

[0055] In a further preferred embodiment, R31 to R35 are H.

[0056] According to a further development of the invention, it is provided that Zi and Z2 are F, and RI and R2 are independently selected from the group consisting of H, F, Cl, Br, CF3, CHF2, CH2F and CH3, with the proviso that at least RI or R2 is Br, Cl, or CF3, preferably Br or Cl.

[0057] According to a further development of the invention, it is provided that Yi and Y3 are CH and Y2 are CR22, preferably with CR22 selected from the group consisting of F, Br, CI, and CN, or Yi are CR21, Y2 are N and Y3 are CR23, preferably with CR21 and CR23 being H or methyl, or Yi are N, Y2 are CR22 and Y3 are N, preferably with CR22 being H or methyl.

[0058] In a preferred embodiment of the invention, RI and R2 are each F or CI.

[0059] According to a further development of the invention, it is provided that the at least one chemical compound is a compound of the general formula II I, where Xi and X2 are independently 0 or S, where R 40 H, Cl or F, preferably H, and where Hal is F, Br or Cl. In a particularly preferred embodiment of the invention, the meso substituent on the BODIPY backbone (4) is -3,5-dichloropyridine, i.e. where Hal is Cl, and R40 is H.

[0060] According to a further development of the invention, it is provided that the at least one chemical compound is a compound of the general formula IV, where Xi and X2 are independently 0 or S, where R 41 H, F, Cl, Br, CF3 or Cl-C4-alkyl, preferably H, particularly preferably H, F or Cl, and wherein Hal is Br, Cl or F.

[0061] According to a further development of the invention, it is provided that the at least one chemical compound is a compound of the general formula V, where Xi and X2 are independently 0 or S, where R 42 H, F,

[0062] Cl, CF3 or Cl-C4-alkyl, and wherein Hal is Br, Cl or F. In a preferred embodiment of the invention, the at least one chemical compound is a compound of the general formula I II , a compound of the general formula VI , and a compound of the general formula I II .

[0063] According to a further development of the invention, it is provided that R 14 and R 16 are independently of one another a non-substituted or halogen, alkyl and / or O-alkyl substituted heterocyclic 5-membered ring having at least one heteroatom selected from S, O and N, preferably O and S, where preferably R19, R17 and R19, or R18 and R19 are substituted, or a non-substituted or halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted homocyclic 6-membered ring, where preferably R32, R33, or R32 and R34 are substituted, or R31 to R35 are H.

[0064] According to a further development of the invention, the compound is selected from the group consisting of:

[0065]

[0066] In a preferred embodiment of the invention, the connection is formed mirror-symmetrically with respect to the axis through B and the meso position is formed.

[0067] A general synthesis for preparing compounds according to the invention with a BODIPY basic structure and a 4-pyridyl meso group is known from Barteilmess et al. ("meso-Pyridyl BODIPYs with tunable chemical, optical and electrochemical properties", New Journal of Chemistry, 37 (9), 2663-2668; 2013). The compounds according to the invention relate in particular to so-called small molecules. Small molecules are understood to be non-polymeric organic molecules with monodisperse molar masses between 100 and 2000 g / mol, which are present in the solid phase under normal pressure (air pressure of the surrounding atmosphere) and at room temperature. In particular, the small molecules are photoactive, where photoactive is understood to mean that the molecules change their charge state and / or their polarization state upon exposure to light.The photoactive molecules show in particular an absorption of electromagnetic radiation in a certain wavelength range, whereby absorbed electromagnetic radiation, i.e. photons, are converted into excitons.

[0068] According to a further development of the invention, it is provided that the optoelectronic component is an organic optoelectronic component, preferably an organic photovoltaic element, an OFET, an OLED or an organic photodetector, particularly preferably an organic photovoltaic element.

[0069] In a preferred embodiment of the invention, the at least one photoactive layer is an absorber layer, preferably the at least one compound is an absorber material.

[0070] The at least one photoactive layer formed as a planar heterojunction (PHJ) comprises a donor layer with the at least one compound according to the invention as donor and an acceptor layer arranged thereon, preferably arranged directly thereon, with at least one acceptor. The acceptor is preferably a fullerene, particularly preferably C60, or a fullerene derivative. However, the acceptor can also be a non-fullerene acceptor (NFA).

[0071] In an alternative embodiment of the invention, the at least one photoactive layer formed as a planar heterojunction (PHJ) has an acceptor layer with the at least one compound according to the invention as acceptor.

[0072] In a preferred embodiment of the invention, the donor layer of the PHJ cell has a layer thickness of 5 nm to 50 nm, preferably 5 to 20 nm, preferably 7 to 15 nm.

[0073] In a preferred embodiment of the invention, the acceptor layer of the PHJ cell has a layer thickness of 5 nm to 50 nm, preferably 7 to 15 nm, preferably 5 to 20 nm.

[0074] In a preferred embodiment of the invention, the layer system of the optoelectronic component has at least two photoactive layers, preferably at least three photoactive layers, or preferably at least four photoactive layers.

[0075] In a preferred embodiment of the invention, the compound and / or a layer with the at least one compound is deposited by means of gas phase deposition or solvent processing, particularly preferably by means of vacuum processing.

[0076] The object of the present invention is also achieved by providing a use of at least one compound according to the invention in a photoactive layer of an optoelectronic component, preferably an organic optoelectronic component, which is designed as a planar heterojunction (PHJ), in particular according to one of the previously described embodiments. The use of the at least one compound in the optoelectronic component results in particular in the advantages that have already been explained in connection with the optoelectronic component according to the invention with the at least one compound.

[0077] According to a further development of the invention, it is provided that the compound according to the invention is used in an organic optoelectronic component, preferably an organic photovoltaic element, an OLED, an OFET, or an organic photodetector.

[0078] In a preferred embodiment of the invention, the at least one compound according to the invention is used as an absorber material in a photoactive layer of the optoelectronic component. In a preferred embodiment of the invention, the compound according to the invention is used as a donor in a donor-acceptor heterojunction.

[0079] In a preferred embodiment of the invention, the optoelectronic component has a substrate, wherein the first electrode or the second electrode is arranged on the substrate, in particular one of the electrodes of the optoelectronic component can be applied directly to the substrate, wherein the layer system is arranged between the first electrode and the second electrode.

[0080] The object of the present invention is also achieved by providing a chemical compound of general formula II, in particular according to one of the previously described embodiments. The chemical compound of general formula II offers, in particular, the advantages already explained in connection with the optoelectronic component according to the invention. with Yi selected from the group consisting of N and CR21 , where R21 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3 ; with Y2 selected from the group consisting of N and CR22 , where R22 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3 ; with Y3 selected from the group consisting of N and CR23 , where R23 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3 ; with Z1 and Z2 F or CF3; with X1 and X2 independently of one another are O, S or N-R8 with R8 selected from the group consisting of H, alkyl and aryl, where preferably X1 and X2 are S or X1 and X2 are 0; with RI and R2 independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl, CF3, CHF2, CH2F or CH3;wherein R13 and R15 are independently selected from the group consisting of H, halogen, CN, alkyl, O-alkyl, and S-alkyl, preferably H or C1-C4-alkyl; wherein R14 and R16 are independently selected from the group consisting of an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted heterocyclic 5-membered ring or 6-membered ring, preferably with a heteroatom independently selected from S, O and N, and an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted homocyclic 6-membered ring, preferably an unsubstituted and substituted heterocyclic 5-membered ring, and an unsubstituted and substituted homocyclic 6-membered ring.;

[0081] In a preferred embodiment of the invention, in the chemical compound of general formula II, R14 and R16 are a substituted heterocyclic 5-membered ring, wherein at least one H atom, preferably one H atom, of the heterocyclic 5-membered ring is substituted, preferably with a substituent selected from the group consisting of H, halogen, CN, alkyl, O-alkyl, and S-alkyl. In a preferred embodiment of the invention, R14 and / or R16 are not further fused.

[0082] In a preferred embodiment of the invention, in the chemical compound of the general formula II, XI and X2 are S or XI and X2 are 0, particularly preferably Xi and X2 are 0. In a preferred embodiment of the invention, in the chemical compound of the general formula II, at least one H atom in R14 and R16 of the homocyclic 6-membered ring and / or of the heterocyclic 5-membered ring or 6-membered ring is substituted by F or CF3, preferably by F.

[0083] In a preferred embodiment of the invention, in the chemical compound of general formula II, R13 and R15 are H.

[0084] In a preferred embodiment of the invention, in the chemical compound of general formula II, R13 and R15 are the same, and / or R14 and R16 are the same.

[0085] In a preferred embodiment of the invention, in the chemical compound of the general formula IIZI is Z2, R13 is R15, and R14 is R16.

[0086] In a preferred embodiment of the invention, in the chemical compound of the general formula II, XI and X2 are equal to O or S, R13 and R15 are H, and R14 and R16 are an unsubstituted or substituted heterocyclic 5-ring or 6-ring, preferably with a heteroatom selected from S, O and N, or an unsubstituted or substituted homocyclic 6-ring, preferably a substituted heterocyclic 5-ring.

[0087] In a preferred embodiment of the invention, in the chemical compound of the general formula II, R13 and R14 and / or R15 and R16 each form a non-substituted or substituted heterocyclic 5-membered ring or 6-membered ring having at least one heteroatom selected from S, O and N, or a non-substituted or substituted homocyclic 6-membered ring.

[0088] In a preferred embodiment of the invention, in the chemical compound of general formula II, R13 and R14 and / or R15 and R16 each form a non-substituted or substituted heterocyclic 5-membered ring having at least one heteroatom selected from S, O and N. In a preferred embodiment of the invention, the chemical compound of general formula II has no ring structure between R13 and R14 and / or between R15 and R16.

[0089] In a preferred embodiment of the invention, in the chemical compound of the general formula II, R14 and R16 are independently selected from the group consisting of with X3 is O, S, or N-R9 with R9 selected from the group consisting of H, alkyl and aryl; with R17 to R19 and R31 to R35 independently of one another selected from the group consisting of H, halogen, preferably F and Cl, CN, alkyl, preferably Cl-C4-alkyl, O-alkyl, preferably O-Cl-C4-alkyl, and S-alkyl, preferably S-Cl-C4-alkyl, where preferably at least one H atom is substituted by F.

[0090] In a preferred embodiment of the invention, in the chemical compound of general formula II, R17 and / or R18 are H, preferably R17 and R18.

[0091] In a preferred embodiment of the invention, in the chemical compound of general formula II at least R31 and R35 are H.

[0092] In a preferred embodiment of the invention, in the chemical compound of general formula II, R31, R32, R34 and R35 are H.

[0093] In a further preferred embodiment of the invention, in the chemical compound of the general formula II, R31 to R35 are H.

[0094] In a further preferred embodiment of the invention, in the chemical compound of the general formula II, Zi and Z2 are F, and RI and R2 are independently selected from the group consisting of H, F, Cl and Br, with the proviso that at least RI or R2 is Br or Ci.

[0095] In a further preferred embodiment of the invention, in the chemical compound of the general formula II, Yi and Y3 are CH and Y2 are CR22, preferably with CR22, selected from the group consisting of F, Br, CI, and CN, or Yi are CR21, Y2 is N and Y3 is CR23, preferably with CR21 and CR23, H or methyl, or Yi are N, Y2 is CR22 and Y3 is N, preferably with CR22, H or methyl, where in each case R1 and R2 are preferably F or CI.

[0096] In a further preferred embodiment of the invention, the at least one chemical compound is a compound of the general formula II I , where Xi and X2 are independently 0 or S, where R 40 H, Cl or F, preferably H, and where Hal is Br, Cl or F. In a particularly preferred embodiment of the invention, the meso substituent on the BODIPY backbone is (4)-3,5-dichloropyridine, i.e. where Hal is in each case Cl, and R40 is H.

[0097] In a further preferred embodiment of the invention, the at least one chemical compound is a compound of the general formula IV,

[0098] where Xi and X2 are independently 0 or S, where R 41 H, Ci or F, preferably H, and wherein Hal is Br, Ci or F.

[0099] In a further preferred embodiment of the invention, the at least one chemical compound is a compound of the general formula V, where Xi and X2 are independently 0 or S, where R 42 H, Cl-C4-alkyl, CI or F, and wherein Hal is Br, CI or F.

[0100] In a further preferred embodiment of the invention, in the chemical compound of the general formula II R 14 and R 16a non-substituted or substituted heterocyclic 5-membered ring having at least one heteroatom selected from S, O and N, preferably O and S, wherein preferably R19, R17 and R19, or R18 and R19 are substituted, or a non-substituted or substituted homocyclic 6-membered ring, wherein preferably R32, R33, or R32 and R34 are substituted, or R31 to R35 are H. The invention is explained in more detail below with reference to the drawings. In the drawings:

[0101] Fig. 1 is a schematic representation of an embodiment of an optoelectronic component in cross section;

[0102] Fig. 2 is a schematic representation of an embodiment of a synthesis scheme for synthesizing compounds according to the invention; Fig. 3 is a graphic representation of the current-voltage curve, the spectral external quantum yield, and the fill factor of a PHJ cell with the compound (40), measured on an organic optoelectronic component;

[0103] Fig. 4 is a graphical representation of the absorption spectrum of compound ( 40 ) ; and

[0104] Fig . 5 the maximum external quantum efficiency ( EQE max ) several embodiments of compounds according to the invention in an optoelectronic component .

[0105] Examples of implementation

[0106] Fig. 1 shows a schematic representation of an embodiment of an optoelectronic component 10 in cross section.

[0107] In this embodiment, the optoelectronic component 10 is an organic photovoltaic element.

[0108] The optoelectronic component 10 has a substrate 1. Arranged on the substrate 1 are a base electrode 2, a cover electrode 6, and a layer system 7 with at least one photoactive layer 4, wherein the layer system 7 is arranged between the base electrode 2 and the cover electrode 6. The at least one photoactive layer 4 is designed as a planar heterojunction (PHJ). The at least one photoactive layer 4 designed as a planar heterojunction has an acceptor layer and a donor layer. The donor layer of the photoactive layer 4 has at least one chemical compound of the general formula I as a donor. In this exemplary embodiment, the acceptor layer of the photoactive layer 4 has the fullerene C60 as the acceptor; alternatively, the acceptor can also be a fullerene derivative or a non-fullerene acceptor (NFA). The chemical compound of the general formula I has the following structure: with Yi selected from the group consisting of N and CR21, where R21 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Y2 selected from the group consisting of N and CR22, where R22 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Y3 selected from the group consisting of N and CR23, where R23 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Z1 and Z2 independently selected from the group consisting of F, Cl, CN, CF3, C2F5, OCH3, and OC2H5; with RI and R2 independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl, CF3, CHF2, CH2F or CH3;with R3 and R5 independently of one another selected from the group consisting of H, halogen, CN, unsubstituted and aryl or heteroaryl-substituted alkyl, unsubstituted and aryl or heteroaryl-substituted alkenyl, O-alkyl, S-alkyl, a unsubstituted and alkyl-substituted heterocyclic 5-ring and 6-ring, preferably with at least one heteroatom selected from S, O or N, and a unsubstituted and alkyl-substituted homocyclic 6-ring, where the unsubstituted or substituted heterocyclic 5-ring or 6-ring, or the unsubstituted or substituted homocyclic 6-ring can be fused to another unsubstituted or substituted heterocyclic 5-ring or 6-ring;with R4 and R6 independently of one another selected from the group consisting of H, halogen, CN, alkyl, alkenyl, O-alkyl, S-alkyl, a non-substituted and halogen, alkyl and / or O-alkyl substituted heterocyclic 5-membered ring and 6-membered ring, preferably with at least one heteroatom selected from S, O and N, and a non-substituted and halogen, alkyl and / or O-alkyl substituted homocyclic 6-membered ring; where R3 and R4 and / or R5 and R6 can each together form a non-substituted or halogen, alkyl, O-alkyl, aryl and / or substituted heterocyclic 5-membered ring or 6-membered ring, preferably with at least one heteroatom selected from S, O and N, or a non-substituted or halogen, alkyl, O-alkyl, aryl and / or heteroaryl substituted homocyclic 6-membered ring.;

[0109] The general preparation of the compounds according to the invention is known to the person skilled in the art. In this context, particular reference is made to international applications WO2007126052A1 and EP3617214A1.

[0110] In one embodiment of the invention, the optoelectronic component 10 has a layer system 7 with at least one light-absorbing photoactive layer 4, wherein the at least one light-absorbing photoactive layer 4 has the at least one compound of the general formula I.

[0111] In a further embodiment of the 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. In a further embodiment of the invention, the optoelectronic component 10 is designed as a tandem cell, triple cell or multiple cell.

[0112] In one embodiment, the organic photovoltaic element has a substrate 1 made of glass, but the substrate 1 can also be made of a film, e.g. made of PET. On the substrate 1 there is a base electrode 2, e.g. made of ITO. Arranged thereon is the layer system 7 with an electron-transporting layer 3 (ETL) and a photoactive layer 4, which is designed as a planar heterojunction, with at least one compound according to the invention as donor material, and an acceptor material, e.g. fullerene C60. Arranged above this is a p-doped hole-transport layer 5 (HTL) and a cover electrode 6 made of gold or aluminum.

[0113] In one embodiment of the invention, the optoelectronic component 10 comprising a compound of the general formula I in a photoactive layer 4 formed as a planar heterojunction is an organic optoelectronic component, preferably an organic photovoltaic element, an OFET, an OLED or an organic photodetector.

[0114] The organic materials are printed, glued, coated, vapor-deposited, or otherwise applied to the foils in the form of thin films or small volumes. All processes used for electronics on glass, ceramic, or semiconducting substrates are also suitable for producing the thin layers. Vacuum evaporation was used to produce the layer system in the present examples.

[0115] Fig. 2 shows a schematic representation of an embodiment of a synthesis scheme for the synthesis of compounds according to the invention.

[0116] The experimental procedure for the synthesis of compounds of general formula I is shown in Fig. 2.

[0117] General Procedure Step 2-A:

[0118] Aldehyde A (1.00 eq.) was dissolved / suspended in 9 vol of anhydrous ethanol. Ethyl trifluoroacetate (1.50 eq.) was added, and the resulting mixture was cooled to 0°C. Subsequently, sodium methoxide solution (21 wt%, 1.50 eq.) was added, and after 5 min, ethyl 2-azidoacetate (1.50 eq.) was slowly added over 10 min at a temperature below 5°C. The mixture was then stirred at 0°C for 30 min and slowly warmed to room temperature, with stirring continued for 4 hours. The reaction mixture was dissolved in 21 vol of ethanol, the precipitate was filtered off, and washed with chilled, anhydrous ethanol to afford Intermediate B.

[0119] General procedure Step 2-B:

[0120] Intermediate B was dissolved in toluene, and the resulting solution was dried over anhydrous sodium sulfate and filtered. A flask was filled with 43 vol of anhydrous toluene under argon and heated to reflux. The solution of intermediate B was transferred to a dropping funnel and slowly added to the refluxing toluene over 15 min. The resulting solution was heated for a further 15 min. The solvent was removed in vacuo to afford a brown solid as the crude product. The crude product was suspended in 8 vol of petroleum ether and sonicated. The resulting precipitate was filtered off, washed with petroleum ether, and dried in vacuo to afford pyrrole ester C.

[0121] General Procedure Step 3-A:

[0122] Pyrrole ester C (1.00 eq.) was suspended in 19 vol ethanol, and a solution of 5.0 eq. NaOH in 4 vol water was added. The mixture was stirred at 75 °C for 1 hour, and then 7.0 eq. AcOH in 11 vol water was added to obtain a pH of ~4. The product was filtered and washed with water and then toluene to yield pyrrolic acid D.

[0123] General procedure Step 3-B:

[0124] Pyrrolic acid D (1.00 eq.) was dissolved in 21 vol of ethanolamine. The mixture was heated to 150°C and stirred for 4 hours. After cooling to 50°C, 32 vol of heptane was added. The mixture was further cooled to 10°C, the product was filtered off, washed with water and heptane, and dried in vacuo to yield pyrrole E.

[0125] General Procedure Step 4: Pyrrole E (2.00 eq.) and aldehyde (1.00 eq.) were dissolved / suspended in 30 vol dichloromethane. Trifluoroacetic acid (0.10 eq.) was added dropwise at room temperature and the mixture was stirred for 3 hours. p-Chloranil (1.05 eq.) was added dropwise over 5 min and the mixture was mixed at room temperature for 30 min. The mixture was diluted with 25 vol methanol and then concentrated under reduced pressure (40°C in a water bath) to remove most of the dichloromethane. The resulting suspension was then stirred at 0°C for 90 min and then filtered. The isolated solid was washed with cold methanol and dried in vacuo to give dipyrrin F.

[0126] General procedure (synthesis) Step 5:

[0127] Dipyrrin F (1.00 eq.) was suspended in 42 vol of anhydrous toluene. The mixture was stirred at 55°C, and N,N-diisopropylethylamine (1.50 eq.) was added. A solution of boron trifluoride diethyl etherate (4.00 eq.) in 10 vol of anhydrous toluene was slowly added. The mixture was stirred at 55°C until completely dissolved. The reaction mixture was cooled to 0°C and stirred at this temperature for one hour. The precipitate was filtered, washed with toluene and methanol, and then dried in vacuo to afford crude BODIPY G. The crude BODIPY G was purified by recrystallization to afford purified BODIPY G.

[0128] Synthesis of the compounds:

[0129] Synthesis of 5-phenylfuran-2-carbaldehyde A-1

[0130] The synthesis of 5-phenylfuran-2-carbaldehyde A-1 can be carried out according to Li et al. (J. Am. Chem. Soc. 2017, 139 (39) , 13636-13639).

[0131] Synthesis of pyrrole ester Cl

[0132] Using compound 5-phenylfuran-2-carbaldehyde A-1 (8.61 g, 50.0 mmol) after Step 2-A and Step 2-B, compound Cl was isolated as a white to brownish solid (8.33 g, 65% yield). 1H NMR (400 MHz, acetone-d6) 5 10.70 (m, 1H), 7.82 (m, 2H), 7.44 (m, 2H), 7.32 (m, 1H), 7.03 (m, 1H), 6.78 (m, 1H), 4.30 (q, J = 8.0 Hz, 2H), 1.33 (t, J = 8.0 Hz, 3H).

[0133] Synthesis of pyrrolic acid Dl

[0134] Following the general procedure for step 3-A using pyrrole ester Cl (58.0 g, 0.227 mol), compound Dl was isolated as a beige solid (50.3 g, 97% yield).

[0135] Synthesis of Pyrrole El

[0136] Following the general procedure for step 3-B using pyrrolic acid Dl (50.0 g, 0.220 mol), compound El was isolated as a brownish solid (36.6 g, 91% yield). 1H NMR (400 MHz, acetone-d6) 5 9.86 (m, 1H), 7.73 (m, 2H), 7.37 (m, 2H), 7.21 (m, 1H), 6.96 (m, 1H), 6.88 (m, 1H), 6.11 (m, 1H).

[0137] Synthesis of Dipyrrine Fl

[0138] Following the general procedure for step 4 using pyrrole El (5.13 g, 28.0 mmol) and 3,5-dichloro-4-pyridinecarboxaldehyde (2.54 g, 14.0 mmol), compound Fl was isolated as a green crystalline solid (6.30 g, 86% yield).

[0139] Synthesis of BODIPY Gl

[0140] Following the general procedure for step 5 using dipyrrine Fl (6.30 g, 12.1 mmol), compound Gl was isolated and purified by recrystallization from toluene (800 mL). A green crystalline solid was obtained (4.10 g, 60% yield).

[0141] Fig. 3 shows a graphical representation of the current-voltage curve, the spectral external quantum efficiency, and the fill factor of a PH J cell with compound (40), measured on an organic optoelectronic component 10. Identical and functionally identical elements are provided with the same reference numerals, so reference is made to the preceding description. In this embodiment, the optoelectronic component 10 is an organic photovoltaic element.

[0142] To investigate the compounds, i.e., their use as absorber materials in organic optoelectronic components, the current-voltage curve of a PH J cell was measured (Fig. 3A), and the external quantum yield was plotted as a function of wavelength (Fig. 3B). The current-voltage curve contains parameters that characterize the organic photovoltaic element. The most important parameters are the fill factor FF, the open-circuit voltage U oc and the short-circuit current Jsc.

[0143] The current-voltage curve of a PH J-cell with the following structure: glass with ITO / C60 (15 nm) / compound (40) (10 nm, RT) / NHT169 (10 nm) / NHT169:NDP9 (45 nm, 9.9 wt%) / NDP9 (10 nm) / Au (50 nm) was determined. The cell parameters were measured under AMI 0.5 illumination (AM = Air Mass; AM = 1.5). In this spectrum, the global radiant power is 1000 W / m 2; AM = 1.5 as a standard value for the measurement of solar modules), whereby the photoactive layer comprises a planar junction (planar heterojunction - PHJ). In the photoactive layer 4, the donor layer made of compound (40) was applied separately from the acceptor layer made of C60, which is designed as a planar heterojunction. ITO serves as the base electrode 2, and the adjacent fullerene C60 as the electron transport layer (ETL) 3, followed by the photoactive layer 4 with an acceptor layer arranged on the electron transport layer 3 and a donor layer, followed by NHT169 as the hole transport layer (HTL) 5 and NHT169 doped with NDP9. The cover electrode is made of gold. NDP9 is a commercial p-dopant from Novaled GmbH. NHT169 is an HTL matrix material from Novaled GmbH.

[0144] The individual layers of the optoelectronic component 10, in particular the photoactive layer 4, can be applied by evaporating the corresponding material in a vacuum. Compound (40) exhibits good evaporability in a vacuum.

[0145] In the optoelectronic component with connection (40) in a planar heterojunction, the fill factor FF is 73.1%, the open circuit voltage U oc 0.99 V and the short-circuit current Jsc 11.2 mA / cm2. The EQE max of such an organic photovoltaic element is 84%.

[0146] Fig. 4 shows a graphic representation of an absorption spectrum of compound (40). Identical and functionally equivalent elements are provided with the same reference numerals, so that reference is made to the preceding description. The structure of the optoelectronic component 10 corresponds to that of Figure 2; the donor in the photoactive layer 4, formed as a planar heterojunction, is also compound (40).

[0147] The absorption maximum Ämax of compound ( 40 ) is at 743 nm.

[0148] Fig. 5 shows the maximum external quantum efficiency (EQEmax) of several embodiments of compounds according to the invention in an optoelectronic component 10. Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description. In this embodiment, the optoelectronic component 10 is an organic photovoltaic element.

[0149] The structure of the optoelectronic component 10 corresponds to that of Figure 2, wherein the donor in the photoactive layer 4 formed as a planar heterojunction is different in each case.

[0150] The following donors from the compounds of general formula I according to the invention were used:

[0151]

[0152]

[0153] Table 1 shows the absorption maxima λmax of several compounds according to the invention in the film. The optical properties were determined experimentally. The absorption maxima λmax were determined from 30 nm thick vacuum deposited layers on quartz glass using a photometer. Table 1 shows the photovoltaic parameters Uoc, Jsc and FF of several compounds according to the invention with the respective EQE max The maximum EQE is shown as EQE maxand is an essential parameter for describing the efficiency of photovoltaic elements. The efficiency of a photovoltaic element increases with higher EQE max for the corresponding spectral range. The EQE max of the compounds according to the invention is in a range of 60 to 84%.

[0154] Table 1

[0155] An overview of the EQE max For the specific embodiments of the chemical compound of the general formula I according to the invention in PHJ cells of the organic photovoltaic element, the overview in Fig. 5 shows the properties of the compound depending on the meso group on the BODIPY backbone and the lateral groups (corresponding to R14 / R16 of the compound with the general formula I II). The corresponding compound number is given in parentheses. PHJ cells with compounds according to the invention show a particularly high EQE max, in particular in comparison to non-inventive compounds, in particular non-inventive BODIPY compounds which do not have any inventive structural features in the meso-position.

[0156] The experimental data of the compounds according to the invention in photoactive layers 4 formed as planar heterojunctions of organic photovoltaic elements demonstrate that the compounds according to the invention are very well suited as absorber material in planar heterojunctions and lead to an improved efficiency of photovoltaic elements with such photoactive layers 4.

Claims

Patent claims 1. An optoelectronic component, preferably a photovoltaic element, comprising a base electrode, a cover electrode and a layer system with at least one photoactive layer, wherein the layer system is arranged between the base electrode and the cover electrode, wherein at least one photoactive layer is formed as a planar heterojunction (PHJ), and wherein the at least one photoactive layer formed as a planar heterojunction comprises at least one chemical compound of the general formula I, with Yi selected from the group consisting of N and CR21, where R21 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Y2 selected from the group consisting of N and CR22, where R22 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Y3 selected from the group consisting of N and CR23, where R23 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN, CF3 or SF5; with Z1 and Z2 independently selected from the group consisting of F, Cl, CN, CF3, C2F5, OCH3, and OC2H5; with RI and R2 independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl, CF3, CHF2, CH2F or CH3; with R3 and R5 independently selected from the group consisting of H, halogen, CN, unsubstituted and aryl or heteroaryl-substituted alkyl, unsubstituted and aryl- or heteroaryl-substituted alkenyl, O-alkyl, S-alkyl, a unsubstituted and alkyl-substituted heterocyclic 5-ring and 6-ring, preferably having at least one heteroatom selected from S, O or N, and a unsubstituted and alkyl-substituted homocyclic 6-ring, wherein the unsubstituted or substituted heterocyclic 5-ring or 6-ring, or the unsubstituted or substituted homocyclic 6-ring may be fused to another unsubstituted or substituted heterocyclic 5-ring or 6-ring;with R4 and R6 independently selected from the group consisting of H, halogen, CN, alkyl, alkenyl, O-alkyl, S-alkyl, an unsubstituted and halogen-, alkyl-, and / or O-alkyl-substituted heterocyclic 5-membered ring and 6-membered ring, preferably having at least one heteroatom selected from S, O and N, and an unsubstituted and halogen-, alkyl-, and / or O-alkyl-substituted homocyclic 6-membered ring; or wherein R3 and R4 and / or R5 and R6 each together form an unsubstituted or halogen-, alkyl-, O-alkyl-, aryl-, and / or heteroaryl-substituted heterocyclic 5-membered ring or 6-membered ring, preferably having at least one heteroatom selected from S, O and N, or an unsubstituted or halogen-, alkyl-, O-alkyl-, aryl-, and / or heteroaryl-substituted homocyclic 6-membered ring.; 2. Optoelectronic component according to claim 1, wherein Z1 and Z2 are F; and / or wherein R1 and R2 are independently selected from the group consisting of H, F, Cl, Br, CN, CF3, Me, Et, OMe, SMe, OEt, SEt, Pr, and iPr, with the proviso that at least R1 or R2 is Br or Cl, preferably where R1 and R2 are not H; or wherein R1 and R2 are independently selected from the group consisting of Cl, Br, CF3, CN, Me, Et, OMe, SMe, OEt, and SEt, with the proviso that at least R1 or R2 is Cl, Br, CF3, or Me; or where RI and R2 are selected from the group consisting of Br , CI , CF3, CHF2 , and CH2F .

3. Optoelectronic component according to claim 1 or 2, wherein Y is selected from the group consisting of N and CR21, where R21 is H or Cl, and / or wherein Y2 is selected from the group consisting of N and CR22, where R22 is H, CH3, O-CH3, S-CH3, F, Cl, CF3 or SF5, preferably N or CH, and / or wherein Y3 is selected from the group consisting of N and CR23, where R23 is H or Cl; wherein preferably one Y1, Y2, Y3 is an N, or two Y1, Y2, Y3 are an N.

4. Optoelectronic component according to one of the preceding claims, wherein R3 and R4 and / or R5 and R6 form an unsubstituted or substituted heterocyclic 5-ring or 6-ring with at least one heteroatom selected from O, S and N, preferably from O and S, or an unsubstituted or substituted homocyclic 6-ring, or wherein R3 and R4 and / or R5 and R6 form an unsubstituted or substituted heterocyclic 5-ring, preferably a substituted heterocyclic 5-ring, with at least one heteroatom selected from O, S and N, preferably O and S, or an unsubstituted or substituted homocyclic 6-ring, preferably an unsubstituted homocyclic 6-ring. 5 . Optoelectronic component according to one of the preceding claims, wherein the at least one chemical compound is a compound of the general formula II, with Y1 selected from the group consisting of N and CR21, where R21 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3; with Y2 selected from the group consisting of N and CR22, where R22 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3; with Y3 selected from the group consisting of N and CR23, where R23 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3; with Z1 and Z2 being F or CF3; with X1 and X2 independently of one another are O, S or N-R8 with R8 selected from the group consisting of H, alkyl and aryl, where preferably X1 and X2 are S or X1 and X2 are 0; with RI and R2 independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl, CF3, CH2F, CHF2 or CH3;wherein R13 and R15 are independently selected from the group consisting of H, halogen, CN, alkyl, O-alkyl, and S-alkyl, preferably H or C1-C4-alkyl; wherein R14 and R16 are independently selected from the group consisting of an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl-substituted heterocyclic 5-membered ring or 6-membered ring, preferably with a heteroatom independently selected from S, O and N, and an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl-substituted homocyclic 6-membered ring, preferably from an unsubstituted and; substituted heterocyclic 5-membered ring, and an unsubstituted and substituted homocyclic 6-membered ring.

6. Optoelectronic component according to claim 5, wherein R14 and R16 are independently selected from the group consisting of with X3 being O, S, or N-R9 with R9 being selected from the group consisting of H, alkyl and aryl; with R17 to R19 and R31 to R35 being independently selected from the group consisting of H, halogen, preferably F and Cl, CN, alkyl, preferably Cl-C4-alkyl, O-alkyl, preferably O-Cl-C4-alkyl, and S-alkyl, preferably S-Cl-C4-alkyl, where preferably at least one H atom is substituted by F.

7. Optoelectronic component according to claim 5 or 6, with Zi and Z2 being F, and with RI and R2 being independently selected from the group consisting of H, F, Cl, Br, CH3, CH2F, CHF2 and CF3, with the proviso that at least RI or R2 is Br, Cl or CF3.

8. Optoelectronic component according to one of the preceding claims, wherein Yi and Y3 are CH and Y2 are CR22, preferably with CR22 selected from F, Br, Cl, and CN, or Yi are CR21, Y2 are N and Y3 are CR23, preferably with CR21 and CR23 being H or methyl, or Yi are N, Y2 are CR22 and Y3 are N, preferably with CR22 being H or methyl.

9. Optoelectronic component according to one of the preceding Claims, wherein the at least one chemical compound is a compound of general formula III, where Xi and X2 are independently O or S, where R 40 H, Cl or F, preferably H, and wherein Hal is Br, Ci or F.

10. Optoelectronic component according to one of the preceding claims, wherein the at least one chemical compound is a compound of the general formula IV, where Xi and X2 are independently O or S, where R 41 H, F, Cl, Br, CF3 or Cl-C4-alkyl, preferably H or Cl, and wherein Hal is Br, Cl or F.

11. Optoelectronic component according to one of the preceding claims, wherein the at least one chemical compound is a compound of the general formula V, where Xi and X2 are independently 0 or S, where R 42 H, F, Cl, CF3 or Cl-C4 alkyl, and wherein Hal is Br, Cl or F. 12 . Optoelectronic component according to one of the preceding claims, wherein R 14 and R 16 are independently of one another an unsubstituted or halogen, alkyl and / or O-alkyl substituted heterocyclic 5-membered ring having at least one heteroatom selected from S, O and N, preferably O and S, where preferably R19, or R17 and R19, or R18 and R19 are substituted, or an unsubstituted or halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted homocyclic 6-membered ring, where preferably R32, R33, or R32 and R34 are substituted, or preferably R31 to R35 are H.

13. Optoelectronic component according to one of the preceding claims, wherein the compound is selected from the group consisting of:

14. Use of at least one compound according to one of claims 1 to 13 in a photoactive layer formed as a planar heterojunction (PHJ) of an optoelectronic component, preferably an organic optoelectronic component, wherein the organic optoelectronic component is preferably an organic photovoltaic element, an OLED, an OFET, or an organic photodetector.

15. A chemical compound of the general formula II, with Y1 selected from the group consisting of N and CR21, where R21 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3; with Y2 selected from the group consisting of N and CR22, where R22 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3; with Y3 selected from the group consisting of N and CR23, where R23 is H, alkyl, O-alkyl, S-alkyl, a halogen, preferably F or Cl, CN or CF3; with Z1 and Z2 being F or CF3; with X1 and X2 independently of one another are O, S or N-R8 with R8 selected from the group consisting of H, alkyl and aryl, where preferably X1 and X2 are S or X1 and X2 are 0; with RI and R2 independently selected from the group consisting of H, F, Cl, Br, CN, CF3, CHF2, CH2F, Cl-C4-alkyl, O-Cl-C4-alkyl, S-Cl-C4-alkyl, and N-(Cl-C4-alkyl)2, with the proviso that at least RI or R2 is Br, Cl, CF3, CHF2, CH2F or CH3; where R13 and R15 are independently selected from the group consisting of H, halogen, CN, alkyl, O-alkyl, and S-alkyl, preferably H or C1-C4-alkyl; where R14 and R16 are independently selected from the group consisting of an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted heterocyclic 5-membered ring or 6-membered ring, preferably with a heteroatom independently selected from S, O and N, and an unsubstituted and halogen, alkyl, fluorinated alkyl, O-alkyl and / or fluorinated O-alkyl substituted homocyclic 6-membered ring, preferably an unsubstituted and substituted heterocyclic 5-membered ring, and an unsubstituted and substituted homocyclic 6-membered ring.

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