Electronic component comprising a chemical compound of general formula i, ii and / or iii

Abstract

The invention relates to an electronic component comprising an electrode, a counter-electrode and a layer system between the electrode and the counter-electrode, at least one layer of the layer system comprising a chemical compound of general formula I, II, and / or III, and to a use of such a chemical compound of general formula I, II, and / or III in an electronic component.

Description

[0001] Electronic component with a chemical compound of the general formula I, II and / or III

[0002] The present invention relates to an electronic component with an electrode, a counter electrode and a layer system between the electrode and the counter electrode, wherein at least one layer of the layer system comprises a chemical compound of the general formula I, II and / or I II, and to a use of such a chemical compound of the general formula I, II and / or I II in an electronic component.

[0003] Optoelectronic components enable the conversion of electromagnetic radiation into electrical current, or emit electromagnetic radiation when electrical current flows through them.

[0004] Organic solar cells for converting electromagnetic radiation into electrical current comprise at least two electrodes, one electrode being applied to a substrate and the other acting as a counter electrode. Between the electrodes there is at least one photoactive layer and transport layers for charge carriers, in particular electron transport layers and hole transport layers, which are preferably vapor deposited in a vacuum or processed from solution. A structure of an organic solar cell known from the prior art consists of a PIN or NIP diode (Martin Pfeiffer, "Controlled doping of organic vacuum deposited dye layers: basics and applications", PhD thesis TU-Dresden, 1999, and W02011 / 161108A1). A PIN solar cell consists of a substrate with an adjoining usually transparent ground contact, p-layer(s), i-layer(s), n-layer(s) and a cover contact.An nip solar cell consists of a substrate with an adjoining, usually transparent, ground contact, n-layer(s), i-layer(s), p-layer(s) and a cover contact. In the photoactive layers of organic solar cells, photoactive compounds called absorbers are used in a donor / acceptor system, a heterojunction, where at least the donor and / or the acceptor absorbs electromagnetic radiation. The donor / acceptor system can be a planar heterojunction or a bulk heterojunction. The photoactive layers can be made of polymers or small molecules. While polymers are not vaporizable and can therefore only be applied from solutions, small molecules are vaporizable. The absorbers absorb electromagnetic radiation of a specific wavelength, converting photons into excitons that contribute to a photocurrent.The compounds in the donor / acceptor system must exhibit high charge carrier mobility to minimize photocurrent loss due to exciton recombination within the donor / acceptor system. The excitons must be separated into charge carriers at an interface, and the charge carriers must leave the photoactive layer before recombination. To minimize charge carrier recombination, the layers must exhibit high conductivity.

[0005] The efficiency of optoelectronic elements is determined, among other things, by the layers' ability to transport charge carriers. The transport layers must exhibit a certain conductivity, but the conductivity should not be too high. Furthermore, for commercial applications, the conductivity must be maintained over the long lifetime of the electronic component. The materials must therefore be electrochemically stable and exhibit as little diffusion as possible within the transport layer.

[0006] By doping hole transport layers (HTL) with a suitable acceptor material (p-dopant) and / or electron transport layers (ETL) with a suitable donor material (n-dopant), the charge carrier density in layers and the conductivity can be increased, which can also lead to an improved transfer of charge carriers between adjacent layers.

[0007] The use of dopants in organic electronic components, particularly in organic solar cells and organic light-emitting diodes, is known. Various materials have been proposed as dopants, for example, aryl- and / or heteroaryl-substituted main group element halides (DE102007018456B4), metal complexes (W02005086251A2, EP1721347A1), transition metal complexes (DE102008051737), bora-tetraazapentalenes (W02007115540A1), and organic phosphoranes (EP2724388B1). Inorganic dopants such as alkali metals ( e.g. cesium) or Lewis acids ( e.g. FeC13 ; SbC15 ) are usually disadvantageous in organic matrix materials due to their high diffusion coefficients, as the function and stability of the electronic components are impaired (D. Oeter, Ch. Ziegler, W. Göpel Synthetic Metals ( 1993 ) 61 147 ; Y. Yamamoto et al. ( 1965 ) 2015 , J. Kido et al. Jpn J. Appl. Phys. 41 ( 2002 ) L358 ).

[0008] While the dopants disclosed in the prior art are suitable for doping transport layers in electronic components, alternative dopants are required that are freely available and enable sufficient conductivity in layers doped with them. Furthermore, thermal decomposition occurs during evaporation of many known dopants, making it impossible to clean them thoroughly by sublimation or to evaporate them from evaporation sources relevant for production without the formation of decomposition products.

[0009] The present invention is therefore based on the object of providing novel dopants for doping organic layers in electronic components that have sufficiently high redox potentials, do not interfere with the matrix material, and provide an effective increase in conductivity and / or charge carrier density in the matrix material. Furthermore, the dopants should be evaporable for processing in a vacuum.

[0010] The problem is solved by the subject matter of the independent claims. Advantageous embodiments emerge from the subclaims.

[0011] The object is achieved in particular by providing an electronic component with an electrode, a counter electrode, and a layer system between the electrode and the counter electrode. At least one layer of the layer system comprises at least one chemical compound of the general formula I (a quinoline derivative), II (an isoquinoline derivative), and / or III (a quinazoline derivative): wherein no further ring is fused to the basic structure of formula I, II and III, with at least one RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or at least one RI, R2, R3, R4, R5 and R6 in formula III independently of one another form an amino group NR8R9, wherein R8 and R9 are each independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, aryl, heteroaryl with a heteroatom selected from O, S and N, wherein the aryl or heteroaryl can be bridged via a CH2 or C2H4 unit to the N atom of the amino group, and wherein H atoms can each be substituted, wherein the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, with the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4,R5 and R6 in formula III are independently selected from the group consisting of H, halogen, CN, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, where H atoms may each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N. It is assumed that the basic form used, particularly upon evaporation, transforms into a stable cation by the addition of an additional hydrogen atom and the release of an electron to the matrix. Substitution is understood in particular to mean the exchange of H by a substituent. A substituent is understood in particular to mean all atoms and atom groups except H, preferably a halogen, an alkyl group, the alkyl group may be linear or branched, an alkenyl group,an alkynyl group, an amino group, an O-alkyl group, an S-alkyl group, an aryl group, or a heteroaryl group. A halogen is understood to mean, in particular, F, Cl, or Br, preferably F. The alkyl groups are preferably C1-C4 alkyl groups. The aryl or heteroaryl groups are preferably 5-membered or 6-membered rings.

[0012] In a preferred embodiment of the invention, two RI, R2, R3, R4, R5, R6 and R7 in formula I are independently an amino group NR8R9.

[0013] In a preferred embodiment of the invention, one of the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I is selected from the group consisting of H, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S or N, where H atoms may each be substituted, where the substituent is in each case selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S or N.

[0014] In a preferred embodiment of the invention, an RI, R2, R3, R4, R5, R6 and R7 in formula I is an amino group NR8R9, where R8 and R9 are each independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, aryl, heteroaryl having a heteroatom selected from O, S or N, where the aryl or heteroaryl can be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and where H atoms can each be substituted, where the substituent is each selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl having a heteroatom selected from O, S or N, and one of the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I is selected from the group consisting of alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S or N, where H atoms may each be substituted,wherein the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S or N.,

[0015] The chemical compounds refer to so-called small molecules. Small molecules are understood in particular to be non-polymeric organic molecules with monodisperse molar masses between 100 and 2000 g / mol, which exist in the solid phase under normal pressure (air pressure of the surrounding atmosphere) and at room temperature. In particular, the small molecules are photoactive, whereby photoactive means that the molecules change their charge state and / or their polarization state when exposed to light. The photoactive molecules exhibit in particular an absorption of electromagnetic radiation in a specific wavelength range, whereby absorbed electromagnetic radiation, i.e. photons, are converted into excitons.

[0016] The electronic component with the chemical compound has advantages compared to the prior art. Advantageously, new alternative dopants are provided. Advantageously, the chemical compounds are suitable for doping a matrix material, preferably for doping transport materials, in particular electron-transport materials, in particular the chemical compounds have sufficiently high redox potentials for this purpose. Advantageously, the chemical compounds contribute to an increase in the charge carrier density in a matrix material. Advantageously, the compounds have no disruptive influence on the matrix material, in particular on fullerenes. Advantageously, the chemical compounds contribute to an increase in the charge carrier density of the doped matrix material and / or lead to an increased effective charge carrier mobility.Advantageously, the dopants increase the conductivity of charge transport layers and / or the transfer of charge carriers between adjacent layers, in particular an electrode layer and an organic layer, or between two organic layers, is improved. Advantageously, a conductivity achieved at higher temperatures of a layer doped with a chemical compound according to the invention is at least largely retained even after cooling. Advantageously, the chemical compounds have a low oxidation potential, are therefore stable in air and can be used under atmospheric conditions. Advantageously, the chemical compounds are sufficiently thermally stable and can be evaporated in a vacuum, for example by vacuum thermal evaporation (VTE) or organic vapor phase deposition (OVPD); in particular, the chemical compounds do not decompose on evaporation in a vacuum.Advantageously, the chemical compounds are colorless, which at least largely does not lead to a reduction in the efficiency of photovoltaic elements due to parasitic absorption.

[0017] According to a further development of the invention, it is provided that R8 and R9 are each independently selected from the group consisting of H, alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, where the aryl or heteroaryl can be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and where H atoms can each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, aryl, and heteroaryl with a heteroatom selected from O, S and N.

[0018] According to a further development of the invention, it is provided that R8 and R9 are each independently selected from the group consisting of alkyl, preferably methyl, ethyl, propyl, isopropyl, aryl, preferably phenyl or naphthyl, heteroaryl with a heteroatom selected from O, S and N, preferably furanyl or thiophenyl, where the aryl or heteroaryl can be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and where H atoms can each be substituted, where the substituent is selected from the group consisting of amino, alkyl, aryl, and heteroaryl with a heteroatom selected from O, S and N, preferably at least one substituent is an amino group NR10R11, with R10 and R11 independently selected from the group consisting of H, alkyl and aryl, or form R10 and Rll together form a heterocyclic aliphatic or aromatic ring .

[0019] In a preferred embodiment of the invention, at least R8 or R9, preferably R8 and R9, of the amino group NR8R9 is an aryl or a heteroaryl.

[0020] In a preferred embodiment of the invention, at least R8 or R9, preferably R8 and R9, of the amino group NR8R9 are each independently an aryl or heteroaryl having a heteroatom selected from O, S or N, where H atoms can each be substituted, where the substituent is in each case selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl having a heteroatom selected from O, S or N, where preferably at least one substituent is a homocyclic or heterocyclic aliphatic 5-membered ring or 6-membered ring, an aryl or heteroaryl, where the heterocyclic aliphatic ring or the heteroaryl has a heteroatom selected from O, S or N.

[0021] According to a further development of the invention, it is provided that in each case at least R8 or R9 of the amino group NR8R9 is an aryl or a heteroaryl, preferably at least R8 or R9 is an aryl with at least one amino group NR10R11, or R8 and R9 of the amino group NR8R9 are an aryl or a heteroaryl, preferably R8 and R9 are an aryl with in each case at least one amino group NR10R11.

[0022] According to a further development of the invention, at least two R1, R2, R3, R4, R5, R6, and R7 in formula I or formula II, or at least two R2, R3, R4, R5, and R6 in formula III, independently of one another, are an amino group NR8R9. In a preferred embodiment of the invention, R8 and R9 form a homocyclic or heterocyclic aromatic or aliphatic ring.

[0023] According to a further development of the invention, it is provided that the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are independently selected from the group consisting of H and alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, where H atoms can each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, aryl, and heteroaryl with a heteroatom selected from O, S and N.According to a further development of the invention, it is provided that the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are independently selected from the group consisting of H and alkyl, preferably H and Cl-C6-alkyl, particularly preferably H, methyl, ethyl, propyl and isopropyl, and / or the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are the same.

[0024] In a preferred embodiment of the invention, at least one of the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III is not H. In an alternative preferred embodiment of the invention, the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are H.

[0025] In a preferred embodiment of the invention, R1 or R2, and R3 or R4, and R5 or R? in formula I are each independently a non-substituted or substituted aryl or a non-substituted or substituted heteroaryl having a heteroatom selected from O, S and N, wherein the substituent is in each case selected from the group consisting of halogen, amino, alkyl, O-alkyl, S-alkyl, aryl, and heteroaryl having a heteroatom selected from O, S or N.

[0026] In a particularly preferred embodiment of the invention, at least R8 or R9, preferably R8 and R9, of the amino group NR8R9 is an aryl, preferably phenyl, where H atoms of the aryl may be substituted, preferably at least one H atom is substituted with an electron-donating substituent.

[0027] In a preferred embodiment of the invention, R8 and R9 each represent an amino group NR8R9.

[0028] According to a further development of the invention, it is provided that R8 and R9 are independently an aryl or heteroaryl, preferably selected from the group consisting of

[0029] where * represents the linkage to N of the amino group, with R12 to R18 independently selected from the group consisting of H, halogen, CN, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, where H atoms may each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl,

[0030] Alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with one heteroatom selected from O, S and N.

[0031] According to a further development of the invention, it is provided that the chemical compound is a compound of the general formula I, wherein preferably at least R2, at least R3, or at least R6

[0032] Amino group NR8R9, particularly preferred are at least RI and

[0033] R6, at least R3 and R6, at least R3 and R7, at least R2 and R7, or at least R2 and R6 are an amino group NR8R9.

[0034] According to a further development of the invention, it is provided that the chemical compound is a compound of the general formula IV, V or VI wherein preferably RIO and Rll are independently selected from the group consisting of H and alkyl, or RIO and Rl l together form a heterocyclic aliphatic or aromatic ring, wherein H atoms of the basic structure may be substituted, preferably at least one H atom is substituted with a further amino group NR8R9.

[0035] According to a further development of the invention, the chemical compound is selected from the group consisting of: In a preferred embodiment of the invention, the electronic component has at least one photoactive layer, preferably two photoactive layers, or preferably three photoactive layers in the layer system.

[0036] Photoactive is understood in particular to mean that molecules change their charge state and / or their polarization state when exposed to light. Accordingly, a photoactive layer is understood in particular to mean a layer of an electronic component which has photoactive molecules that contribute to the absorption of radiation and / or the emission of radiation. A photoactive layer is understood accordingly to mean a light-absorbing layer or a light-emitting layer. In a preferred embodiment of the invention, at least one photoactive layer is a light-absorbing layer.

[0037] In a preferred embodiment of the invention, the electronic component has two photoactive layers, i.e. is a so-called tandem cell, or three photoactive layers, i.e. is a so-called triple cell.

[0038] According to a development of the invention, it is provided that the chemical compound of the general formula I, II, and / or III in a matrix material, wherein the matrix material has a LUMO energy level of -3.5 eV to -5.0 eV, preferably of -3.0 eV to -4.5 eV, preferably the matrix material is a fullerene, a fullerene derivative, phthalocyanine zinc or CN-HAT, particularly preferably the matrix material is selected from the group consisting of C60, C70, C76, C80, C82, C84, C86, C90 and C94. The chemical compound of the general formula I, II, and / or III is homogeneously distributed in the matrix material or forms a gradient in the matrix material. In a preferred embodiment of the invention, the matrix material is the matrix material of an electron transport layer or an electron injection layer.

[0039] In a preferred embodiment of the invention, the chemical compound of the general formula I, II and / or I II has an oxidation potential E (1 / 2) ox with respect to Fe / Fe+ (ferrocene / ferrocenium) of -0.09 V, preferably -0.6 V.

[0040] In a preferred embodiment of the invention, the matrix material has a reduction potential of -0.3 V compared to Fe / Fe+ (ferrocene / ferrocenium), preferred by -0.5 V, or preferably -0.8 V. The reduction potential of fullerene C60 is E re d=- 0.98V compared to Fc / Fc+.

[0041] Fe / Fe+ refers to the ferrocene / ferrocenium redox couple, which is used as a reference in determining the electrochemical potential by cyclic voltammetry. The oxidation potential toward ferrocene / ferrocenium can be determined by cyclic voltammetry according to IUPAC recommendations (Gritzner, G.; Kuta, J. Pure Appl. Chem. 1984, 56, 461-466).

[0042] In a preferred embodiment of the invention, at least one transport layer, preferably an electron transport layer, of the layer system has the at least one chemical compound as a dopant, preferably as an n-dopant.

[0043] In a preferred embodiment of the invention, the at least one layer with the at least one chemical compound is in direct contact with an electrode, is an electron-transport layer, and / or an electron-injection layer, or is in direct contact with such a layer, or is a layer of a pn junction (connection unit). The electron-injection layer is preferably arranged between an electrode and an electron-transport layer.

[0044] According to a further development of the invention, the chemical compound of the general formula I, II, and / or III is an n-dopant for doping an electron-transport layer, an electron-injection layer, or a layer of a connecting unit (pn junction) of the layer system. The electron-transport layer can be a layer of a connecting unit (pn junction) or, alternatively, can be arranged between an electrode and a photoactive layer. The pn junction is, in particular, a connecting unit between two photoactive layers.

[0045] In a preferred embodiment of the invention, the n-dopant is present in the matrix material in a proportion of 0.1 to 30%, preferably 1 to 30%, preferably 5 to 20%, based on the molar proportion in the matrix material.

[0046] In a preferred embodiment of the invention, the doped electron transport layer has a layer thickness of 1 to 100 nm, preferably from 2 to 50 nm, preferably from 2 to 20 nm, preferably from 5 to 100 nm, preferably from 5 to 50 nm, preferably from 5 to 30 nm, preferably from 10 to 100 nm, preferably from 10 to 50 nm, preferably from 10 to 20 nm, or preferably from 10 to 40 nm.

[0047] In a preferred embodiment of the invention, the doped electron in ection layer has a layer thickness of 0.1 to 50 nm, preferably from 0.1 to 30 nm, preferably from 0.1 to 20 nm, preferably from 0.5 to 50 nm, preferably from 0.5 to 30 nm, preferably from 0.5 to 20 nm, preferably from 1 to 40 nm, or preferably from 1 to 20 nm.

[0048] According to a further development of the invention, it is provided that the electronic component is an organic electronic component, preferably an organic optoelectronic component, wherein the layer system has at least one photoactive layer, preferably the organic electronic component is an organic light-emitting diode (OLED), an organic photovoltaic element (OPV), a battery, an organic field-effect transistor (OFET), or an organic photodetector, or a thermal sensor.

[0049] An organic electronic component is understood, in particular, to be an organic photovoltaic element with at least one organic photoactive layer. An organic photovoltaic element makes it possible to convert electromagnetic radiation into electrical current by utilizing the photoelectric effect. Organic electronic components can be manufactured in various ways. The layers of the layer system can be applied in liquid form as a solution or dispersion by printing or coating, or by vapor deposition in a vacuum, for example using CVD, PVD, or OVPD.

[0050] In a preferred embodiment of the invention, the electronic component is designed as a nip, ni, ip, pnip, pni, pip, nipn, nin, ipn, pnipn, or pipn cell or a combination of nip, ni, ip, pnip, pni, pip, nipn, nin, ipn, pnipn, or pipn cells which contain at least one i-layer. An i-layer is understood in particular to be an intrinsic undoped layer. One or more i-layers can consist of one material (planar heterojunction, PHJ) or of a mixture of two or more materials (bulk heterojunction, BHJ).

[0051] In a preferred embodiment of the invention, the photoactive layer has a donor / acceptor system. In a preferred embodiment of the invention, the at least one donor is an ADA oligomer and / or a BODIPY, and the at least one acceptor is an ADA oligomer and / or a fullerene and / or fullerene derivative. A BODIPY compound is understood to mean, in particular, a compound of the general formula C9H7BN2F2 as the basic structure, i.e., a compound having a boron difluoride group with a dipyrromethene group, in particular a compound 4,4-Dif luoro-4-bora-3a,4a-diaza-s-Indacene. An ADA oligomer is understood to mean, in particular, a conj ugated acceptor-donor-acceptor oligomer (ADA ' oligomer ) with an acceptor unit (A) and a further acceptor unit (A ' ), each of which is bound to a donor unit (D).

[0052] In a preferred embodiment of the invention, the electrodes are made of a metal, preferably Al, Ag, Au or a combination thereof, a conductive oxide, preferably ITO, ZnO:Al or another TCO (Transparent Conductive Oxide), a conductive polymer, preferably PEDOT / PSS poly (3,4-ethylenedioxythiophene) poly (styrenesulfonate) or PANI (polyaniline), or a combination of these materials.

[0053] In a particularly preferred embodiment of the invention, the layer doped n-type with the at least one chemical compound is a layer of a connecting unit (pn-junction) that connects one photoactive layer to another photoactive layer in a tandem solar cell or in a multi-junction solar cell. The connecting unit (pn-junction) comprises at least one n-type layer and one p-type layer, with an interlayer in the form of a further n-type layer that has the chemical compound as an n-dopant preferably being arranged between the n-type layer and the p-type layer.

[0054] In a preferred embodiment of the invention, the layer doped n-type with the at least one chemical compound is in direct contact with an electrode, preferably a cathode, wherein the electrode is preferably formed from oxide conductors such as ITO, ZnO or ZnO:Al (AZO) or metals such as Al, Au or Ag, wherein an ohmic contact behavior is ensured.

[0055] In a preferred embodiment of the invention, the layer n-doped with the at least one chemical compound is in direct contact with an adjacent p-doped layer, preferably a p-doped hole transport layer (HTL) in a connection unit, in order to form a charge carrier generation layer (CGL) for an OLED and / or a recombination layer for an OPV.

[0056] In a preferred embodiment of the invention, the layer with the chemical compound is arranged directly on an electron-transport layer. In a preferred embodiment of the invention, the layer n-doped with the at least one chemical compound is in direct contact with another n-doped layer with a deeper LUMO in order to form an ohmic contact behavior between the two n-doped layers.

[0057] In a preferred embodiment of the invention, the layer n-doped with the at least one chemical compound is in direct contact with an undoped photoactive layer which has a donor-acceptor junction formed as a planar heterojunction (PHJ) or bulk heterojunction (BHJ), or an undoped, electron-conducting intermediate layer, in particular made of fullerene C60, which is arranged between the n-doped layer and the photoactive layer.

[0058] The object of the present invention is also achieved by providing a use of a chemical compound of the general formula I, II and / or III as a dopant in an electronic component, preferably as an n-dopant, for doping at least one layer in a layer system of the electronic component, in particular according to one of the previously described embodiments. The use of the chemical compound of the general formula I, II and / or III in an electronic component results in particular in the advantages already explained in connection with the electronic component.

[0059] The synthesis of compounds of general formulas I, II, and III according to the invention is known to the person skilled in the art. A scheme for the synthesis of chemical compounds of general formula I is presented below. The synthesis is demonstrated using the example of chemical compound (01) (Scheme A) and the example of chemical compound (02) (Scheme B).

[0060] Synthesis of compound (01)

[0061] Synthesis of compound (02)

[0062]

[0063] The invention is explained in more detail below with reference to the exemplary embodiments. In particular, it has been shown that a chemical compound of the general formula I, II or III is suitable for n-doping a layer of an electronic component, in particular an electron-transport layer with the matrix material C60, whereby the conductivity of the layer system is increased.

[0064] Fig. 1 shows, in one embodiment, a schematic representation of an electronic component with a layer system between an electrode and a counter electrode in cross section;

[0065] Fig. 2 shows in one embodiment the electrical conductivity of a layer of C60 with different proportions of doping with compound (01); and

[0066] Fig. 3 shows in one embodiment the electrical conductivity of a layer of C60 with different proportions of doping with compound (02).

[0067] Examples of implementation

[0068] Fig. 1 shows, in one embodiment, a schematic representation of an electronic component 1 with a layer system 8 between an electrode 3 and a counter electrode 8 in cross section. In this embodiment, the electronic component 1 is an organic photovoltaic element.

[0069] The electronic component 1 has an electrode 3, a counter electrode 7, and a layer system 8 between the electrode 3 and the counter electrode 7. The layer system 8 comprises a photoactive layer 5 and the transport layers 4, 6.

[0070] At least one layer of the layer system 8 comprises at least one chemical compound of the general formula I, II, and / or III: wherein no further ring is fused to the basic structure of formula I, II and III, with at least one RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or at least one RI, R2, R3, R4, R5 and R6 in formula III independently of one another form an amino group NR8R9, wherein R8 and R9 are each independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, aryl, heteroaryl with a heteroatom selected from O, S and N, wherein the aryl or heteroaryl can be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and wherein H atoms can each be substituted, wherein the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, with the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4,R5 and R6 in formula III are independently selected from the group consisting of H, halogen, CN, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl having a heteroatom selected from O, S and N, where H atoms may each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl having a heteroatom selected from O, S and N.

[0071] In one embodiment of the invention, R8 and R9 are each independently selected from the group consisting of H, alkyl, aryl, heteroaryl having a heteroatom selected from O, S and N, where the aryl or heteroaryl may be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and where H atoms may each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, aryl, and heteroaryl having a heteroatom selected from O, S and N.

[0072] In a further embodiment of the invention, at least two RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or at least two RI, R2, R3, R4, R5 and R6 in formula III are independently an amino group NR8R9.

[0073] In a further embodiment of the invention, at least R8 or R9 of the amino group NR8R9 is an aryl or a heteroaryl, preferably at least R8 or R9 is an aryl with at least one amino group NR10R11, or R8 and R9 of the amino group NR8R9 are an aryl or a heteroaryl, preferably R8 and R9 are an aryl with at least one amino group NR10R11.

[0074] In a further embodiment of the invention, the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are independently selected from the group consisting of H and alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, where H atoms may each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, aryl, and heteroaryl with a heteroatom selected from O, S and N.

[0075] In a further embodiment of the invention, the chemical compound is selected from the group consisting of:

[0076]

[0077] In a further embodiment of the invention, the chemical compound of the general formula I, II, and / or III is present in a matrix material, wherein the matrix material has a LUMO energy level of -3.5 eV to -5.0 eV, preferably of -3.0 eV to -4.5 eV, preferably the matrix material is a fullerene, a fullerene derivative, or CN-HAT, particularly preferably the matrix material is selected from the group consisting of C60, C70, C76, C80, C82, C84, C86, C90 and C94. In a preferred embodiment of the invention, the matrix material is an electron transport material (ETM).

[0078] In a further embodiment of the invention, the chemical compound of the general formula I, II, and / or III is an n-dopant for doping an electron transport layer, an electron injection layer, or a layer of a pn junction of the layer system 8. The n-dopant is present in the matrix material in a proportion of 0.1 to 30%, preferably 1 to 30%, preferably 5 to 20%, based on the molar proportion in the matrix material. In a further embodiment of the invention, the electronic component 1 is an organic electronic component 1, preferably an organic optoelectronic component, wherein the layer system 8 has at least one photoactive layer 5, preferably the organic electronic component 1 is an organic light-emitting diode (OLED), an organic photovoltaic element (OPV), an organic field-effect transistor (OFET), or an organic photodetector, or a thermal sensor, or a battery.The optoelectronic component 1 has in particular at least one light-absorbing photoactive layer 5.

[0079] In this exemplary embodiment, the electronic component 1 has a substrate 2 made of glass; alternatively, the substrate 2 can be a transparent film. An electrode 3 is arranged on the substrate 2 and is made, for example, from metal, a conductive oxide, in particular ITO (indium tin oxide), ZnO:Al or another transparent, conductive oxide or polymer, such as PEDOT:PSS or PANI. A layer system 8 is arranged on the electrode 3 and comprises a transport layer 4, designed as an n-doped electron transport layer 4 (ETL). A photoactive layer 5 is arranged on the transport layer 4 and comprises at least one donor and one acceptor material, in particular with a p-conducting donor material and an n-conducting acceptor material, e.g. C60 fullerenes, which together form a donor-acceptor system, either as a shallow heterojunction (PHJ) or as a bulk heterojunction (BHJ).Arranged above this is a transport layer 6, in particular a p-doped hole transport layer 6 (HTL), and the counter electrode 7 made of aluminum. In this exemplary embodiment, the electron transport layer 4 (ETL) is n-doped with a compound according to the invention. The photoactive layer 5 in this exemplary embodiment is designed as a bulk heterojunction (BHJ), with a donor and fullerene C60 as acceptor. In this exemplary embodiment, the electron transport layer 4 has at least one chemical compound of the general formula I.

[0080] The chemical compounds are thermally stable and enable evaporation in high vacuum with a process window between 100°C and 400°C, for example by means of vacuum thermal evaporation (VTE) or organic vapor phase deposition (OVPD).

[0081] Fig. 2 shows, in one exemplary embodiment, the electrical conductivity of a layer of C60 with varying amounts of doping with compound (O1). Identical and functionally equivalent elements are provided with the same reference numerals, so reference is made to the preceding description.

[0082] The conductivity of a layer of fullerene C60 doped with compound (01) as an n-dopant as a matrix material was determined. To dope the layer, the matrix material was co-evaporated with compound (01), and the conductivity of the thus doped layer was investigated. The layer contains the chemical compound (01) in proportion to the matrix material C60 at a doping concentration of

[0083] 8.8 wt.% and 15.8 wt.%. The electrical conductivity of such a doped layer is shown in Fig. 2.

[0084] To determine the specific conductivity sigma, high vacuum (2 x 10~ 6mbar) by co-evaporation of fullerene C60 and the respective compound as dopant onto a glass substrate on which structured ITO electrodes were located. The ITO electrodes have a distance a of 1.3 mm and a width b of 7.6 mm. After deposition of the doped layers, they are heated to 100°C for a period of 20 minutes and then cooled again. Thermal annealing increases the conductivity of these doped layers. To determine the conductivity, a voltage U of 10 V was applied, and the current I through the organic layer between two ITO electrodes was measured. The specific conductivity sigma of such a layer was determined by neglecting contact resistances of a layer of thickness d: sigma = I / U a / (b*d)

[0085] The conductivity of the layer with C60 as matrix material increases when doped with the compound (01) compared to a non-doped layer of C60 and is 8.5 -IO when doped at a proportion of 8.8 wt.% -6 S / cm and in a proportion of

[0086] 15.8 wt.% at 1.2 -IO -5 S / cm. In contrast, the conductivity of an undoped layer of C60 is 10~ 8 S / cm or lower.

[0087] Doping with compound (01) can significantly increase the conductivity of C60. The increased electrical conductivity due to doping with compound (01) as an n-dopant is largely irreversible, so that even at a lower temperature, the increase in conductivity of heated layers is largely maintained.

[0088] Fig. 3 shows in one embodiment the electrical conductivity of a layer of C60 with different proportions of doping with compound (02).

[0089] The conductivity of a fullerene C60 layer doped with compound (O2) as an n-dopant as a matrix material was determined. The doped layer was prepared according to the procedure shown in Fig. 2, and the conductivity was measured accordingly.

[0090] The conductivity of the layer with C60 as matrix material increases when doped with the compound (02) compared to a non-doped layer of C60 and is 6.4 -IO at a doping of 10.8 wt.% -4 S / cm and a proportion of 16.1 wt.% at 4.9 -10~ 3 S / cm. In contrast, the conductivity of an undoped layer of C60 is 10~ 8 S / cm or lower.

[0091] The exemplary embodiments demonstrate that doping a matrix material with a chemical compound according to the invention leads to increased conductivity compared to an undoped matrix material. In particular, it was demonstrated that the conductivity of the matrix material C60 can be increased with the compounds (01) and (02) according to the invention compared to a layer of undoped fullerene C60. The conductivity of the layers doped with the chemical compounds (01) and (02) is at least largely maintained or even increased at higher temperatures.

[0092] In one embodiment, the compound (O2) was used to dope a layer in a layer system 8 of an electronic component 1. Identical and functionally identical elements are provided with the same reference numerals, so reference is made to the preceding description. In this embodiment, the electronic component 1 is an organic photovoltaic element having a photoactive layer 5.

[0093] The materials are printed, glued, coated, vapor-deposited or applied in some other way onto the substrate 2 in the form of thin films or small volumes. The substrate 2 can be glass or a film, for example. All methods that are also used for electronics on glass, ceramic or semiconducting carriers can be used to produce the thin layers. To produce the layer system 8, vacuum evaporation of the individual layers of the layer system 8 with the electrodes 3, 7 was used in the present exemplary embodiments. The materials were applied by evaporating the corresponding material in a vacuum. To form the layer doped with the chemical compound, the chemical compound can be co-evaporated at the same time as the matrix material, so that a specific doping ratio is obtained.Alternatively, the layers can also be deposited by means of vapor deposition or solvent processing.

[0094] In this embodiment, the compound (O2) was used as an n-dopant to dope an electron-transport layer 4 between an electrode 3 and a photoactive layer 5 of the layer system. In the photoactive layer 5, C60 was used as the acceptor and absorber O14 as the donor in the donor / acceptor heterojunction.

[0095] The layer structure of layer system 8 is summarized in Table 1 .

[0096] Table 2

[0097]

[0098] ITO: Indium Tin Oxide

[0099] NHT49: commercial hole conductor from Novaled GmbH

[0100] NDP9: commercial p-dopant from Novaled AG

[0101] NDN45: commercial n-dopant from Novaled AG

[0102] Absorber014 :

[0103] The layers were deposited on a PET film as a substrate with ITO ground contact in high vacuum (2xlCh 6 mbar). The deposition rates for all layers were selected so that the total rate of co-evaporated materials was between 0.03 and 0.06 nm / s. Mixed evaporation ratios and doping densities refer to mass fractions. For all layers without an explicit temperature specification, the substrate temperature during deposition was 30+ / -5°C. 100 nm of aluminum (Al) was evaporated through a shadow mask as a cover contact.

[0104] Doped n-ETL layers (4) with C60 as matrix material were used: Type A: fullerene C60 doped with 10 wt.% NDN45 (reference) , and type B: fullerene C60 doped with 10 wt.% compound (02) .

[0105] The current-voltage characteristics of the organic photovoltaic

[0106] The element was measured and the parameters fill factor FF, open circuit voltage Voc, and short circuit current Jsc with the compound (O2) were determined. The parameters of the organic photovoltaic element were measured under simulated AMI . 5 illumination (AM = Air Mass; AM = 1.5). In this spectrum, the global radiant power is 1000 W / m 2 ; AM = 1 , 5 as standard value for measuring solar modules).

[0107] Within the limits of measurement accuracy, the same photovoltaic parameters Jsc = 9.8 mA / cm 2 , Voc = 0 . 85 V and FF = 69 . 7%, which corresponds to an efficiency of 5 . 8% .

[0108] In a further embodiment, the compound (02) was used to dope a layer in a layer system 8 of an electronic component 1. In this embodiment, the electronic component 1 is an organic photovoltaic element, which is designed as a tandem cell with two photoactive layers 5. The production of the organic photovoltaic element corresponds to that in the previous embodiment.

[0109] In this embodiment, compound (O2) was used as an n-dopant to dope an n-type layer of a connecting unit (pn junction) between two photoactive layers of the layer system. In the photoactive layers, C60 was used as the acceptor and AbsorberO14 as the donor in the donor / acceptor heterojunction.

[0110] The layer structure of layer system 8 is summarized in Table 2 .

[0111] Table 2

[0112]

[0113] Different doped n-ETL layers of the pn-junction with C60 as matrix material were used: Type C: fullerene C60 doped with 20 wt.% NDN45 (reference), type D: fullerene C60 doped with 10 wt.% compound (02), and type E: fullerene C60 doped with 20 wt.% compound (02).

[0114] The current-voltage characteristics of the organic photovoltaic element were measured according to the previous embodiment and the parameters fill factor FF, open circuit voltage Voc, and short circuit current Jsc with the compound (02) were determined.

[0115] Within the limits of measurement accuracy, the same photovoltaic parameters Jsc = 6.7 mA / cm 2 , V oc= 1.73 V and FF = 71% were measured, corresponding to an efficiency of 8.2%. In particular, the high fill factor FF demonstrates that the n-doping of C60 with compound (02) works efficiently, resulting in a quasi-ohmic contact behavior at the interface between the ETL on one side and the doped p-HTL on the other. In contrast, inefficient doping or too low doping densities would result in an s-shaped characteristic curve with a greatly reduced fill factor, as the pn junction would form a counter diode.

[0116] The chemical compounds according to the invention are suitable as n-dopants for doping a layer in a layer system 8 of an electronic component 1. It has also been shown that the compound (02) is advantageous as a weak dopant for the performance of an organic photovoltaic element.

Claims

Patent claims 1. Electronic component with an electrode, a counter electrode and a layer system between the electrode and the counter electrode, characterized in that at least one layer of the layer system comprises at least one chemical compound of the general formula I, II, and / or III: wherein no further ring is fused to the basic structure of formula I, II and III, with at least one RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or at least one RI, R2, R3, R4, R5 and R6 in formula III independently of one another an amino group NR8R9, wherein R8 and R9 are each independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, aryl, heteroaryl with a heteroatom selected from O, S and N, wherein the aryl or heteroaryl can be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and wherein H atoms can each be substituted can, wherein the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, with the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III independently of one another selected from the group consisting of H, halogen, CN, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, where H atoms can each be substituted, wherein the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N.

2. Electronic component according to claim 1, wherein R8 and R9 are each independently selected from the group consisting of H, alkyl, aryl, heteroaryl having a heteroatom selected from O, S and N, wherein the aryl or heteroaryl may be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and wherein H atoms may each be substituted, wherein the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, aryl, and heteroaryl having a heteroatom selected from O, S and N.

3. Electronic component according to claim 1 or 2, wherein R8 and R9 are each independently selected from the group consisting of alkyl, preferably methyl, ethyl, propyl, isopropyl, aryl, preferably phenyl or naphthyl, heteroaryl with a heteroatom selected from O, S and N, preferably furanyl or thiophenyl, where the aryl or heteroaryl can be bridged to the N atom of the amino group via a CH2 or C2H4 unit, and where H atoms can each be substituted, where the substituent is selected from the group consisting of amino, alkyl, aryl, and heteroaryl with a heteroatom selected from O, S and N, preferably at least one substituent is an amino group NR10R11, with R10 and R11 independently selected from the group consisting of H, alkyl and aryl, or R11 and R11 form together form a heterocyclic aliphatic or aromatic ring .

4. Electronic component according to one of the preceding claims, wherein in each case at least R8 or R9 of the amino group NR8R9 is an aryl or a heteroaryl, preferably at least R8 or R9 is an aryl with at least one amino group NR10R11, or R8 and R9 of the amino group NR8R9 are an aryl or a heteroaryl, preferably R8 and R9 are an aryl with in each case at least one amino group NR10R11.

5. Electronic component according to one of the preceding claims, wherein at least two RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or at least two RI, R2, R3, R4, R5 and R6 in formula III are independently an amino group NR8R9.

6. Electronic component according to one of the preceding claims, wherein the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are independently selected from the group consisting of H and alkyl, aryl, heteroaryl having a heteroatom selected from O, S and N, where H atoms may each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, aryl, and heteroaryl having a heteroatom selected from O, S and N.

7. Electronic component according to one of the preceding claims, wherein the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are independently selected from the group consisting of H and alkyl, preferably H and C1-C6-alkyl, particularly preferably H, methyl, ethyl, propyl and isopropyl, and / or the remaining RI, R2, R3, R4, R5, R6 and R7 in formula I or formula II, or the remaining RI, R2, R3, R4, R5 and R6 in formula III are the same, preferably each H. 8 . Electronic component according to one of the preceding Claims , wherein R8 and R9 independently of each other are aryl or Heteroaryl, preferably selected from the group consisting of where * represents the linkage to N of the amino group, with R12 to R18 independently selected from the group consisting of H, halogen, CN, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N, where H atoms may each be substituted, where the substituent is selected from the group consisting of amino, alkyl, alkenyl, alkynyl, O-alkyl, S-alkyl, aryl, heteroaryl with a heteroatom selected from O, S and N.

9. Electronic component according to one of the preceding claims, wherein the chemical compound is a compound of the general formula I, wherein preferably at least R2, at least R3, or at least R6 is an amino group NR8R9, particularly preferably at least R1 and R6, at least R3 and R6, at least R3 and R7, at least R2 and R7, or at least R2 and R6 are an amino group NR8R9.

10. Electronic component according to one of the preceding claims, wherein the chemical compound is a compound of the general formula IV, V or VI wherein preferably RIO and Rll are independently selected from the group consisting of H and alkyl, or RIO and Rl l together form a heterocyclic aliphatic or aromatic ring, wherein H atoms of the basic structure may be substituted, preferably at least one H atom is substituted with a further amino group NR8R9.

11. Electronic component according to one of the preceding claims, wherein the chemical compound is selected from the group consisting of:

12. Electronic component according to one of the preceding claims, wherein the chemical compound of the general formula I, II, and / or III is present in a matrix material, preferably an electron transport material, wherein the matrix material has a LUMO energy level of -3.5 eV to -5.0 eV, preferably of -3.0 eV to -4.5 eV, preferably the matrix material is a fullerene, a fullerene derivative, or CN-HAT, particularly preferably the matrix material is selected from the group consisting of C60, C70, C76, C80, C82, C84, C86, C90 and C94.

13. Electronic component according to one of the preceding claims, wherein the chemical compound of the general formula I, II, and / or III is an n-dopant for doping an electron transport layer, an electron injection layer, or a layer of a pn junction of the layer system, wherein the n-dopant is preferably present in the matrix material in a proportion of 0.1 to 30%, preferably from 1 to 30%, or preferably from 5 to 20% based on the molar proportion in the matrix material.

14. Electronic component according to one of the preceding claims, wherein the electronic component is an organic electronic component, preferably an organic optoelectronic component, wherein the layer system has at least one photoactive layer, preferably the organic electronic component is an organic light-emitting diode (OLED), an organic photovoltaic element (OPV), a battery, an organic field-effect transistor (OFET), or an organic photodetector, or a thermal sensor.

15. Use of a chemical compound of the general formula I, II and / or III according to one of claims 1 to 11 as a dopant in an electronic component, preferably as an n-dopant, for doping at least one layer in a layer system of the electronic component.

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