Dopant and conductor materials

Abstract

The present invention provides a dopant capable of forming a conductor material having high conductivity. The present invention relates to a dopant comprising a radical cation and a counter anion represented by the following formula (1). In the following formula (1), R 1 ~R 3 are the same or different and represent a monovalent aromatic group or a group represented by the following formula (r). 1 ~R 3 At least one of them is a group represented by the following formula (r). n represents the valence of the radical cation, which is equal to the number of nitrogen atoms (n) in the formula. 1 ,Ar 2 ,Ar 3 The same or different, indicating a divalent aromatic group, Ar 4 ,Ar 5 ,Ar 6 ,Ar 7 are the same or different and represent a monovalent aromatic group which may have a substituent represented by the following formula (sb). m and n are the same or different and represent an integer greater than 0.

Description

Technical Field

[0001] The present disclosure relates to a novel dopant and a conductor material obtained by using the dopant. The present disclosure claims priority to Japanese Patent Application No. 2020-074089 filed in Japan on April 17, 2020, the contents of which are incorporated herein by reference. Background Art

[0002] Conjugated polymer compounds are used as materials for various electronic devices due to their light weight and excellent moldability. In addition, conjugated polymer compounds are given high conductivity by doping with a dopant.

[0003] Among the dopants, there are donors (ie, N-type dopants) that inject electrons as carriers and acceptors (ie, P-type dopants) that attract electrons and form holes.

[0004] As a representative acceptor, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) can be cited. For example, the following example is recorded in Non-Patent Document 1: F4-TCNQ is doped into PBTTT-C16 (poly[2,5-bis(3-hexadecylthiophene-2-yl)thieno[3,2-b]thiophene]) as a conjugated polymer compound to prepare a P-type conductive polymer.

[0005] Prior art literature

[0006] Non-patent literature

[0007] Non-patent document 1: R. Fujimoto et al. Org. Electron. 47 (2017), 139-146 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] However, it is known that the doping efficiency of F4-TCNQ is low. Specifically, it is known that F4-TCNQ has a weak ability to attract electrons from PBTTT-C16 (that is, oxidizing power). Moreover, even if F4-TCNQ obtains electrons attracted from PBTTT-C16 and becomes an anion, the anion is unstable and easily dedoped.

[0010] In addition, in the case of a dopant having a low doping efficiency, the low doping efficiency can be compensated by using a large amount of the dopant, but if the dopant is used in a large amount, a new problem of blocking the conductive path will arise.

[0011] Therefore, it is known that it is difficult to form a conductor material with high conductivity using F4-TCNQ.

[0012] Therefore, an object of the present disclosure is to provide a dopant capable of forming a conductor material having high conductivity.

[0013] Another object of the present disclosure is to provide a conductor material having high conductivity obtained by using the dopant.

[0014] Another object of the present disclosure is to provide a method for manufacturing a conductor material having high conductivity using the dopant.

[0015] Another object of the present disclosure is to provide an electronic device having a conductor material with high conductivity.

[0016] Technical Solution

[0017] The inventors of the present invention have conducted in-depth research to solve the above problems, and found that: an ionic compound composed of a radical cation and a counter anion represented by the following formula (1) has a high oxidizing power; after the radical cation attracts electrons from a conjugated polymer compound, the counter anion is released from the ionic bond with the radical cation and stably stored in the gap of the crystal structure of the conjugated polymer compound, so it is not easy to dedope; and the crystallinity of the conjugated polymer compound can be improved by storing the counter anion. The present disclosure is completed based on these insights.

[0018] That is, the present disclosure provides a dopant comprising a radical cation represented by the following formula (1) and a counter anion.

[0019] [Chemical formula 1]

[0020]

[0021] [In formula (1), R 1 ~R 3 are the same or different and represent a monovalent aromatic group or a group represented by the following formula (r). 1 ~R 3 At least one of them is a group represented by the following formula (r). n represents the valence of the radical cation, which is equal to the number of nitrogen atoms (n) in the formula.]

[0022] [Chemical formula 2]

[0023]

[0024] (In formula (r), Ar 1 ,Ar 2 ,Ar 3 The same or different, indicating a divalent aromatic group, Ar 4 ,Ar 5 ,Ar 6 ,Ar7 are the same or different and represent a monovalent aromatic group optionally having a substituent represented by the following formula (sb). m and n are the same or different and represent an integer greater than 0. The wavy bond in the formula is bonded to the nitrogen atom in formula (1).

[0025] [Chemical formula 3]

[0026]

[0027] (In formula (sb), Ar 8 ,Ar 9 The same or different, indicating a divalent aromatic group, Ar 10 ,Ar 11 ,Ar 12 ,Ar 13 are the same or different and represent a monovalent aromatic group. s and t are the same or different and represent an integer greater than 0. The wavy bond in the formula is bonded to the monovalent aromatic group.

[0028] The present disclosure also provides a dopant as described above, wherein the counter anion is a nitrogen anion, a boron anion, a phosphorus anion, or an antimony anion.

[0029] The present disclosure also provides a conductive material, wherein the conductive material has a structure in which the dopant is doped into a conjugated polymer compound.

[0030] The present disclosure also provides a method for producing a conductive material, wherein the dopant is doped into a conjugated polymer compound to obtain a conductive material having a structure in which the conjugated polymer compound is doped with the dopant.

[0031] The present disclosure also provides an electronic device comprising the conductive material.

[0032] Effects of the Invention

[0033] The dopant disclosed in the present invention has excellent oxidizing power and is not easily dedoped. Therefore, if the dopant is doped into a conjugated polymer compound, a conductive material with high conductivity can be obtained.

[0034] In addition, if the dopant is doped into a conjugated polymer compound, the crystallinity of the conjugated polymer compound is improved, and a conductor material with high stability (stability against heat, water, electricity, etc.) can be obtained. Therefore, according to the dopant, a conductor material with both high conductivity and high stability can be realized.

[0035] The conductor material obtained by using the dopant has both high conductivity and high crystallinity. In addition, the conductor material is flexible. Moreover, it can be formed into a film by a simple method and is easy to be applied to a large area. Therefore, if the conductor material is used, an electronic device that is light-weight, thin, flexible, and has a large area and the like can be realized while suppressing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a graph showing the ultraviolet-visible-near infrared absorption spectra of the conductor materials obtained in Examples and Comparative Examples. DETAILED DESCRIPTION

[0037] [Dopant]

[0038] The dopant disclosed in the present invention is an ionic compound (also referred to as a salt or an ion pair) comprising a radical cation and a counter anion represented by the following formula (1). The dopant may be a metal compound or a metal complex.

[0039] The dopant acts as a P-type dopant. Furthermore, since the dopant contains a plurality of radical cations, it has excellent oxidizing power and easily attracts electrons from the conjugated polymer compound. That is, it has excellent doping efficiency.

[0040] In addition, when the free radical cation attracts electrons from the conjugated polymer compound and is converted into a neutral compound, the counter anion is released from the ionic bond with the free radical cation. Then, the counter anion is stored in the gap of the crystal structure of the conjugated polymer compound. Thus, the crystallinity of the conjugated polymer compound is improved and the stability is improved.

[0041] (Radical cation)

[0042] The radical cation is represented by the following formula (1).

[0043] [Chemical formula 4]

[0044]

[0045] [In formula (1), R 1 ~R 3 are the same or different and represent a monovalent aromatic group or a group represented by the following formula (r). 1 ~R 3 At least one of them is a group represented by the following formula (r). n represents the valence of the radical cation, which is equal to the number of nitrogen atoms (n) in the formula.]

[0046] [Chemical formula 5]

[0047]

[0048] (In formula (r), Ar 1 ,Ar 2 ,Ar 3 The same or different, indicating a divalent aromatic group, Ar 4 ,Ar 5 ,Ar 6 ,Ar 7 The same or different, represents a monovalent aromatic group. The monovalent aromatic group optionally has a substituent represented by the following formula (sb). m and n are the same or different, and represent an integer greater than 0. The wavy bond in the formula is bonded to the nitrogen atom in formula (1).

[0049] [Chemical formula 6]

[0050]

[0051] (In formula (sb), Ar 8 ,Ar 9 The same or different, indicating a divalent aromatic group, Ar 10 ,Ar 11 ,Ar 12 ,Ar 13 are the same or different and represent a monovalent aromatic group. s and t are the same or different and represent an integer greater than 0. The wavy bond in the formula is bonded to the monovalent aromatic group in formula (r).

[0052] m, n, s, and t each represent an integer greater than 0, for example, an integer from 0 to 5, preferably an integer from 0 to 3, and particularly preferably an integer from 0 to 2. As the values ​​of m, n, s, and t increase, the doping efficiency into the conjugated polymer compound tends to increase, and the crystallinity of the conjugated polymer compound after doping tends to increase.

[0053] When m, n, s, and t are each an integer of 2 or more, there are plural groups shown in parentheses, and these groups may be the same or different.

[0054] The monovalent aromatic group is a group formed by removing a hydrogen atom from the structural formula of an aromatic compound [more specifically, a group formed by removing a hydrogen atom bonded to a carbon atom (a carbon atom or a heteroatom when the aromatic compound is an aromatic heterocycle) constituting the aromatic compound].

[0055] The divalent aromatic group is a group formed by removing two hydrogen atoms from the structural formula of an aromatic compound [more specifically, a group formed by removing two hydrogen atoms bonded to a carbon atom (a carbon atom or a heteroatom when the aromatic compound is an aromatic heterocycle) constituting the aromatic compound].

[0056] The aromatic compounds include aromatic hydrocarbons and aromatic heterocycles.

[0057] The aromatic hydrocarbons include: aromatic hydrocarbon rings having 6 to 14 carbon atoms, such as benzene and naphthalene; and compounds in which two or more aromatic hydrocarbon rings are bonded via a single bond or a linking group.

[0058] Examples of the linking group include: 1-5 Alkylene group, carbonyl group (-CO-), ether bond (-O-), thioether bond (-S-), ester bond (-COO-), amide bond (-CONH-), carbonate bond (-OCOO-), etc.

[0059] As the aromatic hydrocarbon, at least one compound selected from the group consisting of compounds represented by the following formulae (ar-1) to (ar-6) is preferred.

[0060] [Chemical formula 7]

[0061]

[0062] Examples of the aromatic heterocycle include: a monocyclic aromatic heterocycle having carbon atoms and at least one heteroatom (e.g., an oxygen atom, a sulfur atom, a nitrogen atom, a phosphorus atom, etc.) as atoms constituting the ring; and a condensed ring formed by condensing the monocyclic aromatic heterocycle with one or more aromatic hydrocarbon rings. Specific examples thereof include pyrrole, furan, thiophene, phosphole, pyrazole, imidazole, oxazole, isoxazole, thiazole, indole, benzofuran, benzothiophene, isoindole, isobenzofuran, benzophosphole, benzimidazole, benzoxazole, benzothiazole, benzisoxazole, indazole, benzisothiazole, benzotriazole, purine, pyridine, phosphinine, pyrimidine, pyrazine, pyridazine, triazine, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, hexazine, quinoline, isoquinoline, quinoxaline, quinazoline, cinnoline, pteridine, phthalazine, acridine, 4aH-phenoxazine, and carbazole.

[0063] The monovalent aromatic group and the divalent aromatic group may have a substituent. Examples of the substituent include a halogen atom, a C 1-5 Alkyl, oxo, hydroxy, substituted oxy (e.g., C 1-5 Alkoxy, C 1-5 acyloxy, etc.), carboxyl, substituted oxycarbonyl (e.g., C 1-5 alkoxycarbonyl), substituted or unsubstituted carbamoyl, cyano, nitro, amino, substituted amino (e.g., mono-C 1-5 Alkylamino or di-C 1-5 Alkylamino, mono C 1-5 Amide or di-C1-5 As the substituent, a halogen atom is preferred, and a bromine atom is particularly preferred.

[0064] In addition, the monovalent aromatic group may have, in addition to the above-mentioned substituent, a group represented by the following formula (sb-1). 13 ,Ar 14 The monovalent aromatic group in can be exemplified by the same examples as those mentioned above.

[0065] [Chemical formula 8]

[0066]

[0067] [Wherein, Ar 13 ,Ar 14 The same or different, represents a monovalent aromatic group. The wavy bond in the formula is bonded to a carbon atom (a carbon atom or a heteroatom when the aromatic compound is an aromatic heterocycle) constituting the aromatic compound.]

[0068] (Counter anion)

[0069] The counter anion is a monovalent or divalent or higher-valent anion, and examples thereof include nitrogen anions, boron anions, phosphorus anions, and antimony anions.

[0070] As the counter anion, a monovalent counter anion is preferred. Also, as the counter anion, a nitrogen anion is preferred.

[0071] Therefore, as the counter anion, an anion represented by the following formula (2) is preferred.

[0072] [Chemical formula 9]

[0073]

[0074] (Where R 6 , R 7 The same or different, represents an electron-attracting group. 6 , R 7 They are optionally bonded to each other to form a ring together with the adjacent nitrogen atom.)

[0075] Examples of the electron-attracting group include a nitro group, a cyano group, a (C 1-5 ) acyl, carboxyl, (C 1-5 ) alkoxycarbonyl, halo(C 1-5 ) alkyl, sulfonyl, (C 1-5 ) alkylsulfonyl, halogenated sulfonyl, halogenated (C 1-5 ) alkylsulfonyl, etc.

[0076] As R 6 , R 7 , wherein preferably halosulfonyl, haloalkylsulfonyl, or R 6 With R 7 They are bonded to each other to form a sulfonyl-haloalkylene-sulfonyl group.

[0077] Examples of the halogenated sulfonyl group include a fluorosulfonyl group and a chlorosulfonyl group.

[0078] Examples of the halogenated alkylsulfonyl group include fluoroalkylsulfonyl groups (e.g., fluoromethylsulfonyl, trifluoroethylsulfonyl, trifluoropropylsulfonyl, pentafluoropropylsulfonyl, etc.); 1-5 Alkylsulfonyl; trifluoromethylsulfonyl, pentafluoroethylsulfonyl, pentafluoropropylsulfonyl, nonafluorobutylsulfonyl and other perfluoro C 1-5 alkylsulfonyl); chloroalkylsulfonyl (e.g., chloromethylsulfonyl, etc. 1-5 Alkylsulfonyl) etc.

[0079] As the R 6 With R 7 Examples of the halogenated alkylene group in the sulfonyl-halogenated alkylene-sulfonyl group bonded to each other include fluoroalkylene groups (e.g., perfluoro C 2-hydroxy-1,2-diyl, 1,3-hexafluoropropane, 1,4-octafluorobutane, etc.) 1-5 alkylene); chloroalkylene (e.g., perchloro-C 1-5 alkylene, etc.).

[0080] As the counter anion, an anion represented by the following formula (2a) is particularly preferred.

[0081] [Chemical formula 10]

[0082]

[0083] (Where R 8 , R 9 are the same or different and represent a halogen atom or a halogenated alkyl group. 8 , R 9 are optionally bonded to each other to form a haloalkylene group. )

[0084] Examples of the halogenated alkyl group include fluoroalkyl groups (e.g., fluoromethyl, trifluoroethyl, trifluoropropyl, pentafluoropropyl, etc.); 1-5 Alkyl; trifluoromethyl, pentafluoroethyl, pentafluoropropyl, nonafluorobutyl and other perfluoro C 1-5 alkyl); chloroalkyl (e.g., chloromethyl, etc. chloro C 1-5 Alkyl) etc.

[0085] Examples of the halogenated alkylene group include fluoroalkylene groups (for example, perfluoroalkylene groups such as tetrafluoroethylene, hexafluoropropane-1,3-diyl, and octafluorobutane-1,4-diyl); 1-5 alkylene); chloroalkylene (e.g., perchloro-C 1-5 alkylene, etc.).

[0086] (Method for producing dopant)

[0087] The dopant containing the radical cation represented by formula (1) and the counter anion can be produced, for example, through the following steps.

[0088] [1] A compound represented by the following formula (1′) is reacted with an oxidizing agent to form an ionic compound (1) containing a radical cation represented by the formula (1).

[0089] [2] The ionic compound (1) is reacted with the ionic compound (2) containing a counter anion.

[0090] [Chemical formula 11]

[0091]

[0092] [In formula (1'), R 1 ~R 3 are the same or different and represent a monovalent aromatic group or a group represented by the following formula (r'). 1 ~R 3 At least one of them is a group represented by the following formula (r').]

[0093] [Chemical formula 12]

[0094]

[0095] (In formula (r'), Ar 1 ,Ar 2 ,Ar 3 The same or different, indicating a divalent aromatic group, Ar 4 ,Ar 5 ,Ar 6 ,Ar 7 The same or different, represents a monovalent aromatic group. The monovalent aromatic group optionally has a substituent represented by the following formula (sb'). m and n are the same or different, and represent an integer greater than 0. The wavy bond in the formula is bonded to the nitrogen atom in formula (1').

[0096] [Chemical formula 13]

[0097]

[0098] (In formula (sb'), Ar8 ,Ar 9 The same or different, indicating a divalent aromatic group, Ar 10 ,Ar 11 ,Ar 12 ,Ar 13 are the same or different and represent a monovalent aromatic group. s and t are the same or different and represent an integer greater than 0. The wavy bond in the formula is bonded to the monovalent aromatic group in formula (r').

[0099] The compound represented by the formula (1′) added in the reaction of step [1] can be produced by, for example, coupling reaction (for example, Sholl-type coupling reaction) of a halide of a triarylamine using an oxidizing agent such as 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ).

[0100] Examples of the oxidizing agent include NOPF6, ferric chloride (FeCl3), iodine, TFSI (trifluoromethanesulfonyl imide) salt, etc. These may be used alone or in combination of two or more.

[0101] The amount of the oxidizing agent used is, for example, about 1 to 5 mol per 1 mol of the compound represented by formula (1').

[0102] The reaction in step [1] can be carried out in the presence of a solvent. Examples of the solvent include aromatic hydrocarbons such as benzene and toluene; halogenated hydrocarbons such as 1,2-dichloromethane; esters such as ethyl acetate; etc. These solvents can be used alone or in combination of two or more.

[0103] The reaction atmosphere in step [1] is not particularly limited as long as it does not inhibit the reaction, and may be, for example, an air atmosphere, a nitrogen atmosphere, an argon atmosphere, or the like.

[0104] The reaction temperature of step [1] is, for example, about -5°C to 30°C. The reaction time is, for example, about 0.5 hour to 5 hours.

[0105] The reaction in step [2] is a reaction in which the anions constituting the ionic compound (1) are exchanged for desired counter anions (for example, nitrogen anions).

[0106] Examples of the ionic compound (2) containing a counter anion include compounds containing a counter anion (X - ) and an ionic compound of a monovalent metal ion. In addition, examples of the metal ions include: Li + 、Na + Alkali metals such as Mg 2 + , Ca 2+ Alkaline earth metals such as Cu +、Ag + 、Au + And other transition metals.

[0107] The reaction in step [2] can be carried out in the presence of a solvent. Examples of the solvent include nitrile solvents such as acetonitrile, propionitrile, and benzonitrile; water; alcohol solvents such as methanol; amide solvents such as N,N-dimethylformamide and N,N-dimethylacetamide; ester solvents such as ethyl acetate; ether solvents such as THF; hydrocarbon solvents such as pentane, hexane, heptane, and octane. These solvents can be used alone or in combination of two or more.

[0108] The reaction atmosphere in step [2] is not particularly limited as long as it does not inhibit the reaction, and may be, for example, an air atmosphere, a nitrogen atmosphere, an argon atmosphere, or the like.

[0109] The reaction temperature of step [2] is, for example, about 0° C. to 30° C. The reaction time is, for example, about 0.5 hour to 10 hours.

[0110] After the reaction is completed, the obtained reaction product can be separated and purified by separation methods such as filtration, concentration, distillation, extraction, crystallization, adsorption, recrystallization, column chromatography, or a combination of these separation methods.

[0111] [Conductor material]

[0112] The conductive material disclosed in the present invention has a structure in which the above-mentioned dopant is doped into a conjugated polymer compound (preferably a crystallized conjugated polymer compound).

[0113] The conductor material is preferably a p-type conductor material. In addition, the conductor material preferably has a counter anion (X - ) is stored in the gaps of the crystal structure of a conjugated polymer compound.

[0114] The radical cation represented by the formula (1) of the above-mentioned dopant has excellent oxidizing power and easily attracts electrons from the conjugated polymer compound. Then, when the above-mentioned dopant is doped into the conjugated polymer compound having a crystal structure, electrons are attracted from the conjugated polymer compound having a crystal structure, and holes as charged carriers are generated. Thus, conductivity is manifested. Then, the radical cation obtains the electrons attracted from the conjugated polymer compound and is converted into a neutral compound. The neutral compound is excluded from the system of the conjugated polymer compound.

[0115] On the other hand, when the radical cation shown in formula (1) is converted into a neutral compound, the counter anion of the dopant is released from the ionic bond with the radical cation and stably stored in the gap of the crystal structure of the conjugated polymer compound. Thus, dedoping can be suppressed and the crystallinity of the conjugated polymer compound can be improved.

[0116] The conductor material shows high conductivity and high crystallinity. The electrical conductivity of the conductor material is, for example, 500 S / cm or more, preferably 1000 S / cm or more, particularly preferably 1200 S / cm or more, and most preferably 1500 S / cm or more. Therefore, it can be preferably used as an electronic device material or an electrode material for a secondary battery.

[0117] In addition, the conductive material is flexible and can be formed into a film by a simple method, and can be easily applied to a large area.

[0118] Therefore, the conductive material can be preferably used for manufacturing electronic devices that can suppress costs and have light weight, thinness, flexibility, and a large area.

[0119] The conductive material can be produced by doping a conjugated polymer compound with the dopant described above.

[0120] The conjugated polymer compound (including oligomers) is preferably a π-conjugated polymer compound, for example, polyacetylenes (trans-polyacetylene, etc.); polyparaphenylenes (polyparaphenylene, polyparaphenylene vinylene (poly(phenylene vinylene)), etc.); polypyrroles (poly(pyrrole-2,5-diyl)), polythiophenes [for example, poly(3-methylthiophene-2,5-diyl), poly(3-hexylthiophene-2,5-diyl) (P3HT), poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT ... oxadiazole-alt-3,6-bis(thiophen-5-yl)-2,5-dioctyl-2,5-dihydropyrrolo[3,4]pyrrole-1,4-dione] (PCBTDPP), poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT), PBTTT-C16 (poly[2,5-bis(3-hexadecylthiophene) [-2-yl)thieno[3,2-b]thiophene]), PBTTT-C14 (poly[2,5-bis(3-tetradecylthiophene-2-yl)thieno[3,2-b]thiophene]), etc.]; polytriarylamines [for example, poly[bis(phenyl-4-yl)-(2,4,6-trimethylphenyl)-amine] (PTAA), poly[bis(phenyl-4-yl)-(4-butylphenyl)-amine] (PolyTPD)], etc.]; polyfluorenes [for example, poly[9,9-dioctylfluorene -co-bis-N,N'-(4-butylphenyl)-bis-N,N'-phenyl-1,4-phenylenediamine] (PFB) and the like]; carbon materials [e.g., fullerenes (e.g., C60 fullerene, C70 fullerene, C76 fullerene, C78 fullerene, C84 fullerene, etc.); graphenes (e.g., graphene, graphene oxide, etc.); carbon nanotubes (e.g., single-layer carbon nanotubes (SWNT), multi-layer carbon nanotubes (MWNT), etc.)] and the like inorganic materials. These may be used alone or in combination of two or more.

[0121] As the conjugated polymer compound, from the viewpoint of having high crystallinity, a heterocyclic conjugated polymer compound is preferred, a heterocyclic conjugated polymer compound containing a nitrogen atom or a sulfur atom as a heteroatom is particularly preferred, a conjugated polymer compound containing a heterocycle having a sulfur atom is particularly preferred, and a conjugated polymer compound containing a thiophene ring structure such as a thiophene ring, a benzothiophene ring, or a thienothiophene ring is particularly preferred.

[0122] Furthermore, as the conjugated polymer compound, a heterocyclic conjugated polymer compound having a side chain is preferred. Then, as the side chain, from the viewpoint of being able to stably store the counter anion of the dopant and further improving the crystallinity, a straight or branched C 6-18 alkyl.

[0123] As the conjugated polymer compound, a polymer compound having a repeating unit represented by the following formula (3) is particularly preferred.

[0124] [Chemical formula 14]

[0125]

[0126] (Where R a ~R d are the same or different and represent a hydrogen atom or an alkyl group having 6 to 18 carbon atoms.

[0127] There is no particular limitation on the method of doping the above-mentioned dopant into a conjugated polymer compound, and examples thereof include the following method: forming a coating film containing the above-mentioned dopant on the surface of the conjugated polymer compound (for example, a film, sheet, coating film, etc. formed by the conjugated polymer compound and having a thickness of about 10 nm to 500 nm).

[0128] As a method for forming a coating film containing the dopant, for example, there can be listed: a method based on a dry process: vacuum evaporation, sputtering, etc.; a method based on a wet process: dissolving and / or dispersing the dopant in a solvent to form a composition, applying the composition to the surface of the conjugated polymer compound, and then removing the solvent by drying.

[0129] Examples of the solvent that can be used in the wet process include nitrile solvents such as acetonitrile, propionitrile, and benzonitrile; water; alcohol solvents such as methanol; amide solvents such as N,N-dimethylformamide and N,N-dimethylacetamide; ether solvents such as THF; ester solvents such as ethyl acetate, etc. These solvents can be used alone or in combination of two or more.

[0130] The dopant concentration (solid content concentration) in the composition in the wet process is, for example, 0.001 to 20% by weight, preferably 0.1 to 5% by weight, and particularly preferably 0.6 to 2% by weight.

[0131] The coating method of the composition in the wet process is not particularly limited, and for example, roll coating, gravure coating, dip coating, spray coating, spin coating, casting, screen printing, inkjet printing, etc. may be used.

[0132] As the drying method in the wet process, natural drying, heat drying, etc. can be adopted. In addition, it is also possible to dry under reduced pressure as needed.

[0133] Furthermore, after drying, an annealing treatment may be performed as necessary.

[0134] [Electronic equipment]

[0135] The electronic device of the present disclosure includes the above-mentioned conductive material. The electronic device may include other components in addition to the above-mentioned conductive material.

[0136] Examples of the electronic device include a conversion element, a diode, a transistor, a photoelectric conversion device, a solar cell, and a photoelectric conversion element (for example, a solar cell element, an organic electroluminescent element, etc.).

[0137] The electronic device includes the above-mentioned conductive material, and thus has both high conductivity and high stability (stability against heat, water, electricity, etc.), and can be made lightweight, flexible, thin, and large in area at low cost.

[0138] The above-mentioned configurations and combinations of configurations of the present disclosure are merely examples, and appropriate additions, omissions, substitutions, and changes of configurations may be made without departing from the gist of the present disclosure.

[0139] Example

[0140] Hereinafter, the present disclosure will be described in more detail by way of examples, but the present disclosure is not limited to the embodiments but only to the description of the claims.

[0141] Example 1 (Preparation of dopant)

[0142] In the presence of N,N-dimethylformamide, triphenylamine (0.25 M) and N-bromosuccinimide (2.0 equivalents) were reacted at 0° C. for 4 hours to obtain a compound represented by the following formula (I).

[0143] [Chemical formula 15]

[0144]

[0145] In the presence of dichloromethane / methanesulfonic acid (9 / 1 (v / v)), the compound represented by formula (I) (0.25 M) was reacted with DDQ (2,3-dichloro-5,6-dicyano-1,4-benzoquinone; 1.5 equivalents) at 0°C for 30 minutes to obtain the compound represented by the following formula (II) (yield: 78%).

[0146] [Chemical formula 16]

[0147]

[0148] In the presence of dichloromethane, the compound represented by formula (II) (0.03M) and nitrosohexafluorophosphate (2.0 equivalents) were mixed at -40°C, then naturally heated to 25°C and reacted at 25°C for 1 hour to obtain the compound represented by the following formula (III) (yield: 32%).

[0149] [Chemical formula 17]

[0150]

[0151] In the presence of acetonitrile, the compound represented by formula (III) (0.01 M) was reacted with lithium bis(trifluoromethanesulfonyl)imide (100.0 equivalents) at 25°C for 1 hour to obtain the compound represented by the following formula (IV) (hereinafter sometimes referred to as "compound (IV)") (yield: 79%).

[0152] The structure of the obtained compound was confirmed by elemental analysis using an organic trace element analyzer (trade name "MICRO CORDER JM10", manufactured by JP-SCIENCE LAB). The results are shown below.

[0153] C: 35.06%, H: 1.93%, N: 4.12% (measured value, sample weight: 1.0266 mg).

[0154] C: 35.21%, H: 1.77%, N: 4.11%, F: 16.71% (theoretical value).

[0155] [Chemical formula 18]

[0156]

[0157] Example 2 (Preparation of a Conductive Material by Doping a Conjugated Polymer Compound with a Dopant)

[0158] A 1 mass % solution of PBTTT-C14 (a conjugated polymer compound having a repeating unit represented by the following formula) in o-dichlorobenzene was spin-coated on a glass substrate (500 rpm×5 seconds, then 2000 rpm×60 seconds), and then annealed at 180°C to obtain a coating film with an average thickness of 50 nm.

[0159] [Chemical formula 19]

[0160]

[0161] The obtained coating film was immersed in an acetonitrile solution (concentration 1.5 mmol / L) of compound (IV) obtained in Example 1 at 60°C for 10 minutes. After immersion, it was spin-dried (1500 rpm×30 seconds) and further dried at 80°C for 10 minutes to obtain a conductive material (1).

[0162] Comparative Example 1 (Preparation of a Conductive Material by Doping a Conjugated Polymer Compound with a Dopant)

[0163] A conductive material (2) was obtained in the same manner as in Example 2 except that F4-TCNQ represented by the following formula was used as a dopant instead of compound (IV).

[0164] [Chemical formula 20]

[0165]

[0166] (Doping efficiency evaluation)

[0167] For PBTTT-C14, the conductor materials (1) and (2) obtained in the examples and comparative examples, ultraviolet-visible-near-infrared (UV-Vis-NIR) absorption spectra were measured in the range of 200 nm to 2700 nm at 1 nm intervals using an ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO). The results are shown in Figure 1 .

[0168] according to Figure 1 , the peak of conductor material (1) near 500nm originating from PBTTT-C14 (neutral) is greatly reduced compared with conductor material (2), and the absorption near 1200nm to 2500nm originating from PBTTT-C14 cation is greatly increased. Therefore, it can be seen that conductor material (1) has a higher doping efficiency than conductor material (2).

[0169] (Crystallinity Evaluation)

[0170] For PBTTT-C14 and the conductive material (1) obtained in Example 1 (=conductive material obtained by doping PBTTT-C14 with compound (IV)), the distance between the polymer main chains (π-stack distance) was measured using an X-ray diffraction device (trade name "SmartLab", manufactured by Rigaku). The measurement results are shown in Table 1 below.

[0171] [Table 1]

[0172]

[0173] As can be seen from Table 1, the distance between polymer main chains (specifically, the distance between adjacent thiophene rings) of the conductive material (1) is shorter than that of PBTTT-C14. This shows that the crystallinity of PBTTT-C14 is improved by doping with the compound (IV).

[0174] (Electrical conductivity evaluation)

[0175] A conductive material (1') was obtained in the same manner as in Example 2 except that a glass plate having a four-terminal measurement proximity electrode was used instead of the glass substrate.

[0176] Moreover, a conductive material (2') was obtained in the same manner as in Comparative Example 1 except that a glass plate having a four-terminal measurement proximity electrode was used instead of the glass substrate.

[0177] The conductivity of the obtained conductor material (1') and conductor material (2') was measured using a digital multimeter (trade name "Keithley 2000 digital multimeter", manufactured by Keithley Corporation) under the measurement condition of a current input of 1 μA.

[0178] As a result, the electrical conductivity of the conductor material (1') was 1500 S / cm.

[0179] Furthermore, the electrical conductivity of the conductor material (2') is 130 S / cm.

[0180] As a summary of the above, the configuration of the present disclosure and its variations are supplementally described below.

[0181] [1] A dopant comprising a radical cation represented by formula (1) and a counter anion.

[0182] [2] The dopant according to [1], wherein the counter anion is a nitrogen anion, a boron anion, a phosphorus anion, or an antimony anion.

[0183] [3] The dopant according to [1], wherein the counter anion is an anion represented by formula (2).

[0184] [4] The dopant according to [1], wherein the counter anion is an anion represented by formula (2a).

[0185] [5] A conductive material having a structure in which a conjugated polymer compound is doped with the dopant according to any one of [1] to [4].

[0186] [6] A p-type conductive material having a structure in which a conjugated polymer compound is doped with the dopant according to any one of [1] to [4].

[0187] [7] The conductive material according to [5] or [6], wherein the conjugated polymer compound is a crystallized conjugated polymer compound.

[0188] [8] The conductive material according to [5] or [6], wherein the conjugated polymer compound is a π-conjugated polymer compound.

[0189] [9] The conductive material according to [5] or [6], wherein the conjugated polymer compound is a heterocyclic conjugated polymer compound.

[0190]

[10] The conductive material according to [5] or [6], wherein the conjugated polymer compound is a heterocyclic conjugated polymer compound containing a nitrogen atom or a sulfur atom as a heteroatom.

[0191]

[11] The conductive material according to [5] or [6], wherein the conjugated polymer compound is a conjugated polymer compound containing a thiophene ring structure.

[0192]

[12] The conductive material according to [5] or [6], wherein the conjugated polymer compound is a polymer compound having a repeating unit represented by formula (3).

[0193]

[13] The conductive material according to any one of [5] to

[12] , wherein the electrical conductivity is 500 S / cm or more.

[0194]

[14] A method for producing a conductive material, comprising doping a conjugated polymer compound with a dopant as described in any one of [1] to [4] to obtain a conductive material having a structure in which the conjugated polymer compound is doped with the dopant.

[0195]

[15] The method for producing a conductive material according to

[14] , wherein the conjugated polymer compound is a crystallized conjugated polymer compound.

[0196]

[16] The method for producing a conductive material according to

[14] , wherein the conjugated polymer compound is a π-conjugated polymer compound.

[0197]

[17] The method for producing a conductive material according to

[14] , wherein the conjugated polymer compound is a heterocyclic conjugated polymer compound.

[0198]

[18] The method for producing a conductive material according to

[14] , wherein the conjugated polymer compound is a heterocyclic conjugated polymer compound containing a nitrogen atom or a sulfur atom as a heteroatom.

[0199]

[19] The method for producing a conductive material according to

[14] , wherein the conjugated polymer compound is a conjugated polymer compound containing a thiophene ring structure.

[0200]

[20] The method for producing a conductive material according to

[14] , wherein the conjugated polymer compound is a polymer compound having a repeating unit represented by formula (3).

[0201]

[21] An electronic device comprising the conductive material according to any one of [5] to

[13] .

[0202] Industrial Applicability

[0203] The dopant disclosed in the present invention has excellent oxidizing power and is not easily dedoped. Therefore, if the dopant disclosed in the present invention is doped into a conjugated polymer compound, a conductive material with high conductivity can be obtained.

[0204] Furthermore, if the conductive material is used, it is possible to realize an electronic device that can suppress costs and has the advantages of being lightweight, thin, flexible, and having a large area.

Claims

1. A dopant comprising a radical cation represented by the following formula (1) and a counter anion represented by the following formula (2), In formula (1), R 1 ~R 3 are the same or different and represent a group formed by removing one hydrogen atom from the structural formula of an aromatic hydrocarbon ring having 6 to 14 carbon atoms and having a halogen atom as a substituent, or a group represented by the following formula (r), and R 1 ~R 3 At least one of them is a group represented by the following formula (r), n represents the valence of the radical cation, which is equal to the number of nitrogen atoms n in the formula, In formula (r), Ar 1 represents a group formed by removing two hydrogen atoms from the structural formula of the following formula (ar-3), Ar 5 ,Ar 6 are the same or different, and represent a group formed by removing one hydrogen atom from the structural formula of an aromatic hydrocarbon ring having 6 to 14 carbon atoms and having a halogen atom as a substituent, m1 and m2 represent 0, and the wavy bond in the formula is bonded to the nitrogen atom in formula (1), In formula (2), R 6 , R 7 Same or different, indicating halogenated C 1-5 Alkylsulfonyl.

2. A conductive material, wherein: The conductive material has a structure in which the dopant according to claim 1 is doped into a conjugated polymer compound.

3. The conductor material according to claim 2, wherein: The conjugated polymer compound is a π-conjugated polymer compound.

4. The conductor material according to claim 2, wherein The conjugated polymer compound is a heterocyclic conjugated polymer compound.

5. The conductor material according to claim 2, wherein The conjugated polymer compound is a heterocyclic conjugated polymer compound containing a nitrogen atom or a sulfur atom as a heteroatom.

6. The conductor material according to claim 2, wherein The conjugated polymer compound is a conjugated polymer compound containing a thiophene ring structure.

7. The conductor material according to claim 2, wherein The conjugated polymer compound is a polymer compound having a repeating unit represented by the following formula (3): In the formula, R a ~R d The same or different groups represent a hydrogen atom or an alkyl group having 6 to 18 carbon atoms.

8. The conductor material according to claim 2, wherein The electrical conductivity of the conductor material is above 500 S / cm.

9. A method for manufacturing a conductive material, wherein: The dopant according to claim 1 is doped into a conjugated polymer compound to obtain a conductive material having a structure in which the conjugated polymer compound is doped with the dopant. 10 . An electronic device comprising the conductive material according to claim 2 .

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