JP2015113448A - Carbon film and element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carbon film which can be obtained by a simple production method such as a coating method, and has a specific width or a specific shape.SOLUTION: Provided is a graphene nanoribbon polymer produced from a polyphenylene polymer, the polyphenylene polymer being formed by benzene rings having two substituted aromatic rings at p-positions, each of the substituted aromatic rings having at a p-position a six-membered ring hydrocarbon containing one or two unsaturated bonds in the ring. The polyphenylene polymer has a group which is soluble in an organic solvent, is dissolved in an organic solvent, and is subjected to wet film-formation. The soluble group is removed to obtain a polyphenylene having only aromaticity, which is further subjected to a dehydrogenation treatment to carry out a ring condensation reaction to form a carbon film. According to the method, a carbon film having a specific width or shape is produced.

Description

  The present invention relates to a carbon film having a specific width or a specific shape and an element using the carbon film.

Carbon materials such as graphene, carbon nanotubes, and fullerenes are attracting attention because they have excellent physical stability and unique physical and electrical characteristics. Among these, graphene nanoribbons with a large aspect ratio of width to shape or width in graphene have the same number of carbon atoms at the end as the proportion of carbon atoms in the bulk environment locally, Since it is foreseen that characteristics such as band gap and electrical conductivity can be intentionally controlled by the chemical structure and width or shape (see Non-Patent Document 1), intensive research has been conducted by each company and research institution. .
Since the graphene does not have an energy gap like a semiconductor, a field effect transistor composed of graphene cannot block an on-current. Therefore, providing a band gap to graphene has become a major issue. As one of the solutions, it has been theoretically and experimentally reported that a band gap is formed when the geometrical shape of graphene is made thin like a ribbon like a carbon nanotube (Non-Patent Document 1, (P74 of Section 5).

There are a top-down method and a bottom-up method as a report on a method for producing such a graphene nanoribbon film.
As the top-down method, for example, a method of producing a graphene nanoribbon film by ultrasonically treating a dispersion of carbon nanotubes and then cleaving and coating the supernatant on a substrate is proposed. (See Patent Document 1).
In addition, a method for producing a graphene nanoribbon film (AFM lithography method) by performing lithography by local anodization using AFM on a graphene film produced by chemical vapor deposition (see Non-Patent Document 2) has been reported. ).
However, these methods are practical because it is difficult to produce a graphene nanoribbon film with a uniform chemical structure, width or shape at the edge, which is very important for property control, and productivity cannot be expected. It was not able to withstand sex.

  On the other hand, as the bottom-up method, for example, by synthesizing a graphene nanoribbon in which a dissolving group is introduced at the end, a solubility is imparted to the originally insoluble graphene nanoribbon, and a graphene nanoribbon film is manufactured by a coating method Has been reported (see Non-Patent Document 3). However, in this report, there is a problem that there is little room for chemical modification of the edge that has a large influence on the property control, and that the excellent properties of the graphene nanoribbon film cannot be obtained by introducing an originally unnecessary dissolving group. It has become.

  In addition, a method for producing a graphene nanoribbon film by forming a low molecular weight, which is a building block of a graphene nanoribbon, on a gold (111) surface by a vacuum deposition method and then heat-treating the molecules to condense the molecule is reported. (See Non-Patent Document 4). However, the method of this report has problems that it is difficult to control the degree of polymerization and that the graphene nanoribbon film can be formed only in an island shape.

  Therefore, in the prior art documents, it is very difficult to obtain a graphene nanoribbon film having a uniform chemical structure, width or shape at the edges by a simple manufacturing method such as a coating method, and a new manufacturing method is provided. It is strongly desired.

  An object of the present invention is to solve the conventional problems and achieve the following objects. That is, an object of the present invention is to provide a carbon film having a specific width or a specific shape obtained by a simple manufacturing method such as a coating method.

  The carbon film of the present invention as a means for solving the problems includes a polyphenylene polymer represented by the following general formula (I), and has a specific width or a specific shape.

<General formula (I)>
However, in said general formula (I), R < ₁ > -R < ₈ > is either selected from a hydrogen atom, a halogen atom, an alkyl group, and an aryl group, respectively. n represents the number of repetitions, and is an integer of 0 to 5. When n is 1 or more, R _{1 to} R ₈ may be the same as or different from each other. X is a group represented by any one of the following general formula 1 and the following general formula 2.

<General formula 1>
However, in General Formula 1, _one of X ₁ and Y ₁ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these may be bonded to each other to form a ring.

<General formula 2>
In General Formula 2, one of X ₂ , X ₃ , Y ₂ , and Y ₃ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these groups may be bonded to each other to form a ring.

  According to the present invention, the conventional problems can be solved, and a carbon film having a specific width or a specific shape obtained by a simple manufacturing method such as a coating method can be provided.

FIG. 1 is a diagram of TG and DSC of the polyphenylene polymer 1 used in the present invention. FIG. 2 is a diagram of absorption spectra of the polyphenylene polymer 1 (soluble polymer) used in the present invention and the polymer film (polymer) from which the soluble groups have been removed. FIG. 3 is a diagram of absorption spectra of the polymer film and the graphene nanoribbon film used in the present invention. 4 shows (1) a spin coat film of polyphenylene polymer 2 used in the present invention, (2) vacuum heating of polyphenylene polymer 2 at 300 ° C., and (3) vacuum heating of polyphenylene polymer 2 at 450 ° C. It is a figure of micro Raman spectroscopy at the time of. FIG. 5 is a diagram of (1) a spin coat film of polyphenylene polymer 2 used in the present invention and (2) an absorption spectrum of polyphenylene polymer 2 when heated at 450 ° C. in a vacuum.

(Carbon film)
The carbon film of the present invention contains a polyphenylene polymer represented by the following general formula (I) and has a specific width or a specific shape.

Here, the specific width in the carbon film is a finite width generated by cutting out single-layer graphene, and the unbonded end portion cut out is a zigzag type, an armchair type, or a combination thereof. .
The specific shape of the carbon film means a shape produced by cutting out single-layer graphene.

<General formula (I)>
However, in said general formula (I), R < ₁ > -R < ₈ > is either selected from a hydrogen atom, a halogen atom, an alkyl group, and an aryl group, respectively. n represents the number of repetitions, and is an integer of 0 to 5. When n is 1 or more, R _{1 to} R ₈ may be the same as or different from each other. X is a group represented by any one of the following general formula 1 and the following general formula 2.

<General formula 1>
However, in General Formula 1, _one of X ₁ and Y ₁ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these may be bonded to each other to form a ring.

<General formula 2>
In General Formula 2, one of X ₂ , X ₃ , Y ₂ , and Y ₃ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these groups may be bonded to each other to form a ring.

The present invention provides a method for producing a carbon film having a specific width or a specific shape by using polyphenylene having a specific soluble group as a raw material. Similar reports have been made on this point (J. AM. CHEM. SOC. 130, 4216 (2008)).
However, since the carbon film of the present invention does not contain an alkyl group or SP ₃ carbon that lowers electrical characteristics and thermal stability, a high-quality carbon film, graphene nanoribbon, and graphite having a specific width or shape are obtained. be able to.
In addition, the graphene nanoribbon has a high carrier / electron transport and has a structure in which only a uniaxial direction is extremely developed. Therefore, the graphene nanoribbon can be used as a conductive wiring by taking advantage of its characteristics and shape.

<Method for producing carbon film>
The method for producing the carbon film will be described based on the following reaction formula A1.

<Reaction Formula A1>
However, the parentheses in the above formula mean repetition. X represents the same meaning as in the general formula I.

Since the polyphenylene having a specific structure used in the present invention has a group soluble in an organic solvent, wet film formation using the organic solvent is possible. In addition, when an external energy is applied, a soluble group (π electron conjugated site) is obtained by removing the soluble group shown in Step 1.
The polyphenylene obtained by the removal of the soluble group in the process 1 generates a carbon film having a specific width or shape by the dehydrogenation process in the process 2 by a ring condensation reaction by hydrogen abstraction. Depending on the thickness of the film, a graphene nanoribbon is obtained in the case of a monomolecular film, and a graphite having a specific width or shape is obtained in a film deposited in a plurality of layers. That is, the major feature is that the width or shape can be determined depending on the initial structure of polyphenylene having a specific structure as a starting material. In addition, the process 1 and the process 2 may proceed simultaneously.

<Polyphenylene raw material having specific soluble group>
Respect polyphenylene which is a raw material of the present invention, the group represented by X ₁ to X _3, Y ₁ to Y ₃ in the general formula 1 and the formula 2 is a hydrogen atom or an optionally substituted C 1 or more carbon atoms also And at least one of X and Y is an optionally substituted ether group having 1 or more carbon atoms or an optionally substituted acyloxy group having 1 or more carbon atoms, and the like. Is a hydrogen atom. By having such a partial structure, solubility can be imparted even with a rigid structure, and high film forming processability can be obtained. Also, by introducing the specific group, the solubility can be improved while the π-conjugated system is expanded, unlike the conventional soluble group.

  The ether group having 1 or more carbon atoms which may be substituted is derived from an alcohol such as a linear or cyclic aliphatic alcohol having 1 or more carbon atoms or an aromatic alcohol having 4 or more carbon atoms. An ether group etc. are mentioned. Further, a thioether group in which an oxygen atom in the ether is replaced with a sulfur atom can also be included. Specifically, for example, methoxy group, ethoxy group, propoxy group, butoxy group, isobutoxy group, pivaloyl group, pentoxy group, hexyloxy group, lauryloxy group, trifluoromethoxy group, 3,3,3-trifluoropropoxy group, Pentafluoropropoxy group, cyclopropoxy group, cyclobutoxy group, cyclohexyloxy group, trimethylsilyloxy group, triethylsilyloxy group, tert-butyldimethylsilyloxy group, tert-butyldiphenylsilyloxy group, etc. Corresponding thioethers in which oxygen is replaced with sulfur are also included.

  Examples of the optionally substituted acyloxy group having 1 or more carbon atoms include, for example, a formyloxy group, a linear or cyclic aliphatic carboxylic acid and a carbonic acid half ester optionally containing a halogen atom having 2 or more carbon atoms, Examples thereof include acyloxy groups derived from carboxylic acids and carbonic acid half esters, such as aromatic carboxylic acids having 4 or more carbon atoms. Moreover, thiocarboxylic acid in which the oxygen atom of the carboxylic acid is replaced with sulfur can also be included. Specifically, for example, formyloxy group, acetoxy group, propionyloxy group, butyryloxy group, isobutyryloxy group, pivaloyloxy group, pentanoyloxy, hexanoyloxy, lauroyloxy group, stearoyloxy group, trifluoroacetyloxy 3,3,3-trifluoropropionyloxy, pentafluoropropionyloxy, cyclopropanoyloxy, cyclobutanoyloxy, cyclohexanoyloxy group, benzoyloxy group, p-methoxyphenylcarbonyloxy group, pentafluorobenzoyloxy group Etc. In addition, the carbonic acid ester derived from the carbonic acid half ester which inserted the oxygen atom or the sulfur atom between the carbonyl group of the acyloxy group illustrated above, and an alkyl group or an aryl group can also be mentioned. In addition, the corresponding acylthiooxy compounds and thioacyloxy compounds in which one or more of oxygen at the ether bond site and carbonyl site are replaced with sulfur are also included.

Here, a part of the substituents X _{1 to} X ₃ and Y _{1 to} Y ₃ will be exemplified below. Et represents an ethyl group and Ph represents a phenyl group.

As the group represented by Q ₁ to Q ₆ in the polyphenylene, as described above, a hydrogen atom, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), or a monovalent organic group (however, In Q ₁ to Q ₆ , an optionally substituted ether group or monovalent organic group other than an acyloxy group having 1 or more carbon atoms is used.
Examples of the monovalent organic group include an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroaryl group, an alkoxyl group, a thioalkoxyl group, an aryloxy group, a thioaryloxy group, a heteroaryloxy group, and a heteroaryl. Examples include a ruthiooxy group, a cyano group, a hydroxyl group, a nitro group, a carboxyl group, a thiol group, and an amino group.

The alkyl group represents a linear or branched or cyclic substituted or unsubstituted alkyl group. Examples thereof include alkyl groups [preferably substituted or unsubstituted alkyl groups having 1 or more carbon atoms [for example, methyl group, ethyl group, n-propyl group, i-propyl group, t-butyl group, s-butyl group]. Group, n-butyl group, i-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group , Octadecyl group, 3,7-dimethyloctyl group, 2-ethylhexyl group, trifluoromethyl group, trifluorooctyl group, trifluorododecyl group, trifluorooctadecyl group, 2-cyanoethyl group]], cycloalkyl group [preferably A substituted or unsubstituted alkyl group having 3 or more carbon atoms [eg, cyclopentyl group, cyclobuty Group, a cyclohexyl group, pentafluoro cyclohexyl]] and the like.
In other monovalent organic groups described below, the alkyl group represents an alkyl group having the above concept.

  The alkenyl group represents a linear or branched or cyclic substituted or unsubstituted alkenyl group. Examples thereof include an alkenyl group [preferably a substituted or unsubstituted alkenyl group having 2 or more carbon atoms and one or more double bonds of any carbon-carbon single bond of the above-described alkyl group having 2 or more carbon atoms. [For example, ethenyl group (vinyl group), propenyl group (allyl group), 1-butenyl group, 2-butenyl group, 2-methyl-2-butenyl group, 1-pentenyl group, 2-pentenyl group Group, 3-pentenyl group, 1-hexenyl group, 2-hexenyl group, 3-hexenyl group, 1-heptenyl group, 2-heptenyl group, 3-heptenyl group, 4-heptenyl group, 1-octenyl group, 2-octenyl group Group, 3-octenyl group, 4-octenyl group, 1,1,1-trifluoro-2-butenyl group]. ], A cycloalkenyl group [which includes one or more double bonds of any carbon-carbon single bond of the cycloalkyl group having 2 or more carbon atoms described above [for example, 1-cycloallyl group, 1-cyclobutenyl group, 1-cyclopentenyl group, 2-cyclopentenyl group, 3-cyclopentenyl group, 1-cyclohexenyl group, 2-cyclohexenyl group, 3-cyclohexenyl group, 1-cycloheptenyl group, 2-cycloheptenyl group, 3-cycloheptenyl group 4-cycloheptenyl group, 3-fluoro-1-cyclohexenyl group]. ] Etc. are mentioned. The alkenyl group may be any of stereoisomers such as trans (E) isomer and cis (Z) isomer, and may be a mixture comprising any ratio thereof. .

  The alkynyl group is preferably a substituted or unsubstituted alkynyl group having 2 or more carbon atoms, wherein one or more triple bonds are formed from any carbon-carbon single bond of the above-described alkyl group having 2 or more carbon atoms. Can be mentioned. Examples of such alkynyl groups include ethynyl group, propargyl group, trimethylsilylethynyl group, and triisopropylsilylethynyl group.

  The aryl group is preferably a substituted or unsubstituted aryl group having 6 or more carbon atoms [eg, phenyl, o-tolyl, m-tolyl, p-tolyl, p-chlorophenyl, p-fluorophenyl, p-trifluoro. Phenyl, naphthyl, etc.].

  The heteroaryl group is preferably a 5- or 6-membered substituted or unsubstituted aromatic or non-aromatic heterocyclic compound [for example, 2-furyl, 2-thienyl, 3-thienyl, 2-thienothienyl. , 2-benzothienyl, 2-pyrimidyl and the like].

  The alkoxyl group and the thioalkoxyl group are preferably a substituted or unsubstituted alkoxyl group and a thioalkoxyl group, and an oxygen atom or a sulfur atom is inserted at the bonding position of the alkyl group, alkenyl group, and alkynyl group exemplified above. Specific examples thereof include alkoxy groups or thioalkoxy groups.

  The aryloxy group and the thioaryloxy group are preferably a substituted or unsubstituted aryloxy group and an arylthiooxy group, and an aryl atom or sulfur atom is inserted into the aryl group exemplified above to form an aryl group. Specific examples include an oxy group or a thioalkoxy group.

  The heteroaryloxy group and heterothioaryloxy group are preferably a substituted or unsubstituted heteroaryloxy group and heteroarylthiooxy group, and an oxygen atom or a sulfur atom at the binding site of the heteroaryl group exemplified above Specific examples include those in which a heteroaryloxy group or a heterothioaryloxy group is inserted.

  The amino group is preferably an amino group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted anilino group [for example, an amino group, a methylamino group, a dimethylamino group, an anilino group, an N-methyl-anilino group. Group, diphenylamino group], acylamino group [preferably formylamino group, substituted or unsubstituted alkylcarbonylamino group, substituted or unsubstituted arylcarbonylamino group, [for example, formylamino, acetylamino, pivaloylamino group, lauroyl Amino, benzoylamino group, 3,4,5-tri-n-octyloxyphenylcarbonylamino group]], aminocarbonylamino group [preferably carbon-substituted or unsubstituted aminocarbonylamino group, [for example, carbamoylamino group] , N, N-Dime Le aminocarbonylamino group, N, N-diethylamino carbonyl amino group, a morpholinocarbonylamino group]] and the like.

The monovalent organic group represented by Q ₁ to Q ₆ can be represented in the above-described range, but is preferably an aryl group or a heteroaryl group which may have a substituent? Or that adjacent groups form a ring structure. More preferably, the cyclic structure is an optionally substituted aryl group or heteroaryl group.
Examples of the ring bond and condensed ring form include the following structures. Incidentally, X and Y is a group defined as for _X 1 _{to X 3,} Y 1 to Y ₃ according to the general formula 1 and 2.

The following are mentioned as an example of the polyphenylene polymer used by this invention. Incidentally, X and Y is a group defined as for _X 1 _{to X 3,} Y 1 to Y ₃ according to the general formula 1 and 2.

More specifically, the following structures are mentioned.

  A side chain is a molecular structure of a chain compound and indicates a portion branched from the longest chain of carbon atoms (main chain). The specific partial structure represented by the general formula 1 or the general formula 2 may be introduced at any position. For example, from the viewpoint of solubility, a preferable result can be obtained even when introduced into the main chain, side chain, or terminal group, but it is more preferable to introduce into the side chain from the viewpoint of both solubility and production. .

The solvent is selected from an aromatic solvent, a halogen solvent, and an ether solvent.
It is preferable that a viscosity adjusting liquid selected from an alcohol solution, a ketone solution, a paraffin solvent, and an alkyl-substituted aromatic solution having 4 or more carbon atoms is further added to the solvent.
Examples of the solvent include benzene, toluene, xylene, ethylbenzene, diethylbenzene, anisole, chlorobenzene, dichlorobenzene, chlorotoluene and the like, an aromatic solvent that may have a halogen; dichloromethane, dichloroethane, chloroform, four Halogenated hydrocarbon solvents such as carbon chloride, tetrachloroethane, and trichloroethane; ether solvents such as dibutyl ether, tetrahydrofuran, and dioxane. These may be used individually by 1 type and may use 2 or more types together.

Examples of the viscosity adjusting liquid include linear or branched alcohol solvents such as methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, nonanol, cyclohexanol, methyl cellosolve, ethyl cellosolve, ethylene glycol, and benzyl alcohol. An alkyl-substituted aromatic solvent having 4 or more carbon atoms, which may have a linear or branched alkyl group, such as butylbenzene, cyclohexylbenzene, tetralin, butylbenzene, and dodecylbenzene; These may be used individually by 1 type and may use 2 or more types together.
Here, if the alcohol-based solution is used as the viscosity adjusting solution, the alcohol-based solution easily absorbs water. Therefore, the storage control of the solution requires attention. However, if the alkyl-substituted aromatic solution having 4 or more carbon atoms is used as the viscosity adjusting solution, it is hydrophobic. Therefore, there is an advantage that it is easy to store.
Further, an alkyl-substituted aromatic solution having 4 or more carbon atoms has an advantage that the viscosity can be adjusted by changing the structure of the alkyl group (for example, lengthening the alkyl chain).
In addition, since the alcohol-based solution has a high viscosity, it is suitable for preparing a solution suitable for a film forming process (for example, an ink jet method) that requires a high solution viscosity.

  In addition, the kind, mixing amount, etc. of the said viscosity adjusting liquid can be suitably selected according to the viscosity required for various film-forming processes. The alkyl-substituted aromatic solution having 4 or more carbon atoms means an aromatic solution having an alkyl substituent having 4 or more carbon atoms. The upper limit of the carbon number of the alkyl substituent is not particularly defined, but for example, the upper limit is about 50. Thus, by selecting a solvent from an aromatic solvent, a halogen solvent, and an ether solvent, the carbon film material can be dissolved in a necessary amount (for example, 1% by mass) or more in the solvent.

Further, when a solution selected from an alcohol solution, a ketone solution, a paraffin solution and an alkyl-substituted aromatic solution having 4 or more carbon atoms is added as the viscosity adjusting solution, the viscosity of the carbon film material-containing solution is increased. Thus, the viscosity can be adjusted to be suitable for various application means (for example, inkjet, nozzle printing, spin coating).
The solvent is at least one selected from an aromatic solvent, a halogen solvent, and an ether solvent, and of course, two or more may be mixed.
Similarly, the viscosity adjusting liquid is at least one selected from an alcohol solution, a ketone solution, a paraffin solution, and an alkyl-substituted aromatic solution having 4 or more carbon atoms. Of course it is good.

<Synthesis example of polyphenylene raw material: Induction of monomer>
A specific method for deriving synthesis examples of polyphenylene raw materials from monomers is disclosed in the following reaction formula A2, but the synthesis method according to the present invention is not limited to these synthesis examples. In the above formula, R ¹ is any one selected from a hydrogen atom, a halogen atom, an alkyl group, or an aryl group (hereinafter the same).

<Reaction Formula A2>

<Example of monomer production>
[Step 1] It can be produced by bromination using AIBN and NBS or bromination using Br ₂ .
[Step 2] A general esterification method or etherification method can be used. For example, tetramethylammonium hydroxide pentahydrate and R-COOH, DBU, base, and R-COOH are also used. can do. It is also easy to form an ether group by using Williamson ether synthesis. Thereby, the acyloxy group used in the present invention, for example, (3) can be formed.
[Step 3] Obtained by Suzuki coupling of dibromodiiodobenzene (4) and a diboron compound. Diboron esters are preferably used. For example, bis (catecholate) diboron, bis (hexylene glycolate) diboron, bis (pinacolato) diboron, bis (neopentyl) diboron and the like are preferably used.
[Step 4] It can be produced by a Suzuki coupling reaction with diiodobenzene.
[Step 5] It can be produced in the same manner as in Step 3.
[Step 6] The compound can be produced by a Suzuki coupling reaction of a compound (3) having an acyloxy group and a diboron (7).
[Step 7] It can be produced by a Suzuki coupling reaction of a diboron dibromo compound and a biphenylboronic acid compound.
[Step 8] Trimethyltin body (10) can be obtained by reacting compound (9) with trimethyltin chloride by adding organolithium, for example, n-BuLi, to lithiate in a dehydrated cryogenic state. .
Thereby, an example of the monomer used by this invention can be manufactured.

<Example of polymer production>
<< Production Example 1 >>

  A copolymer can be synthesized by using the Suzuki coupling reaction between the compound (8) and diboronic acid.

<< Production Example 2 >>
By using a Suzuki coupling reaction between the compound (8) and diboron, homocoupling can be performed. It can also be obtained by using the Yamamoto reaction using the compound (8).

<< Production Example 3 >>
A copolymer can be obtained by using a Stille coupling reaction between the compound (8) and the compound (10).

<Synthesis example of polyphenylene raw material: polymerization>
Hereinafter, the polymerization method will be described in more detail.
Examples of the method for producing the polyphenylene raw material for the carbon film of the present invention include methods such as electric field polymerization, oxidative polymerization, and chemical polymerization. Chemical polymerization is preferable, the bonding sites are selectively bonded, and the molecular weight is high. However, it is easy to obtain a polymer soluble in a solvent.
In order to produce the polyphenylene raw material, a monomer is required, and the method for producing the monomer can be produced by general organic synthesis.

In the method for producing the polyphenylene raw material, the method for condensation polymerization is not particularly limited, and a known condensation reaction can be used depending on the substituent involved in the condensation polymerization. For example, a method of polymerizing a corresponding monomer by a Suzuki coupling reaction, a method of polymerizing by a Grignard reaction, a method of polymerizing by a Stille coupling reaction, a method of polymerizing by a Ni (0) complex, or a polymerization by an oxidizing agent such as FeCl ₃ A known method such as a method or a method of electrochemically oxidative polymerization is exemplified.
Among these, the method of polymerizing by Suzuki coupling reaction, the method of polymerizing by Grignard reaction, the method of polymerizing by Stille coupling reaction, and the method of polymerizing by nickel zero-valent complex are preferable in terms of easy structure control.

A preferable substituent as a substituent involved in the polymerization varies depending on the kind of the polymerization reaction. For example, when a zerovalent nickel complex such as Yamamoto reaction is used, a halogen atom, an alkyl sulfonate group, an aryl sulfonate group, an aryl alkyl sulfonate group Etc. Moreover, when using nickel catalysts or palladium catalysts, such as a Suzuki coupling reaction, an alkyl sulfonate group, a halogen atom, a boric acid ester group, -B (OH) ₂ etc. are mentioned.

The halogen atom of the aryl halide is preferably an iodide or bromide from the viewpoint of reactivity.
In the case of the Grignard reaction, a halide and metal Mg are reacted in an ether solvent such as tetrahydrofuran, diethyl ether, dimethoxyethane or the like to form a Grignard reagent solution, which is mixed with a monomer solution prepared separately, and nickel or An example is a method in which a palladium catalyst is added while paying attention to excess reaction, and then reacted while heating to reflux.
The Grignard reagent is preferably 1 equivalent or more, more preferably 1 equivalent to 1.5 equivalents, still more preferably 1 equivalent to 1.2 equivalents, relative to the monomer. Also in the case of polymerizing by a method other than these, the reaction can be carried out according to a known method.

Examples of the aryl boron compound used in the Suzuki coupling reaction include aryl boronic acid, aryl boronic acid ester, aryl boronic acid salt and the like.
Among these, aryl boronic acid esters are more preferable because they do not produce a dianhydride (boroxine) like aryl boronic acids, are highly crystalline, and are easily purified.

  Examples of the method for synthesizing the aryl boronic acid ester include (i) a method in which an aryl boronic acid and an alkyl diol are heated and reacted in an anhydrous organic solvent, and (ii) metallization of the halogen moiety of the aryl halide, followed by alkoxy (Iii) a method by a reaction by adding an alkoxyboron ester after preparing a Grignard reagent of aryl halogen, (iv) an aryl halide and bis (pinacolato) diboron or bis (neopentyl glycolate) Examples thereof include a method in which diboron is heated and reacted in the presence of a palladium catalyst.

Examples of the palladium catalyst include various catalysts such as Pd (PPh ₃ ) ₄ , PdCl ₂ (PPh ₃ ) ₂ , Pd (OAc) ₂ , PdCl _2, or triphenylphosphine separately added to palladium carbon as a ligand. Can be used. Among these, Pd (PPh ₃ ) _{4 is} particularly preferable.

The Suzuki coupling reaction requires a base, but relatively weak bases such as Na ₂ CO ₃ , NaHCO ₃ , K ₂ CO ₃ give good results. When affected by steric hindrance or the like, strong bases such as Ba (OH) ₂ and K ₃ PO ₄ are effective. Other caustic soda, caustic potash, metal alkoxide, etc., for example, potassium t-butoxide, sodium t-butoxide, lithium t-butoxide, potassium 2-methyl-2-butoxide, sodium 2-methyl-2-butoxide, sodium methoxide, sodium ethoxy And potassium ethoxide.

  Further, a phase transfer catalyst may be used in order to make the reaction proceed more smoothly. Examples of the phase transfer catalyst include tetraalkyl ammonium halide, tetraalkyl ammonium hydrogen sulfate, and tetraalkyl ammonium hydroxide. Preferred examples include tetra-n-butyl ammonium halide, benzyltriethyl ammonium halide, and tricaprylylmethyl ammonium chloride.

  Examples of the reaction solvent include alcohols such as methanol, ethanol, isopropanol, butanol, 2-methoxyethanol, 1,2-dimethoxyethane, and bis (2-methoxyethyl) ether, and ether ethers, and cyclic ethers such as dioxane and tetrahydrofuran. In addition, benzene, toluene, xylene, dimethyl sulfoxide, N, N-dimethylformamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like can be mentioned.

  Examples of the zero-valent nickel complex used in the Yamamoto reaction include bis (1,5-cyclooctadiene) nickel (0), (ethylene) bis (triphenylphosphine) nickel (0), and tetrakis (triphenylphosphine). For example, nickel. Among these, bis (1,5-cyclooctadiene) nickel (0) is preferable.

The reaction temperature of the polymerization reaction is appropriately set depending on the reactivity of the monomer used and the reaction solvent, but it is preferable to keep it below the boiling point of the solvent.
The reaction time in the polymerization reaction can be appropriately set in terms of the reactivity of the monomers used or the molecular weight of the desired polymer, and is preferably 2 hours to 50 hours, more preferably 5 hours to 24 hours.

It is also possible to add a molecular weight regulator in order to adjust the molecular weight in the above polymerization operation, or a sealing agent for sealing the end of the polymer as a terminal modifying group to the reaction system. It is also possible to add it. Accordingly, a group based on a terminator may be bonded to the end of the polymer in the present invention.
Examples of the molecular weight regulator and the end-capping agent include compounds having one reactive group such as phenylboronic acid, bromobenzene, and iodide benzene.

The average molecular weight of the polyphenylene raw material is a number average molecular weight in terms of polystyrene, preferably 1,000 to 1,000,000, and more preferably 2,000 to 500,000.
When the number average molecular weight is too small, the film formability such as generation of cracks is deteriorated and the practicality becomes poor. In addition, since the molecular weight of the carbon film is determined by the molecular weight of the raw material, a low molecular weight is not preferable. On the other hand, when the number average molecular weight is too large, the solubility in a general organic solvent is deteriorated, the viscosity of the solution becomes high and coating becomes difficult, which is also a practical problem.

  The polyphenylene raw material used in the present invention obtained as described above is used after removing impurities such as bases, unreacted monomers, terminal terminators used in the polymerization, and inorganic salts generated during the polymerization. For these purification operations, conventionally known methods such as reprecipitation, extraction, Soxhlet extraction, ultrafiltration, dialysis and the like can be used.

<Removal of soluble groups from polyphenylene raw material>
The removal of the soluble group of the polyphenylene raw material is removed by the elimination reaction of the substituent leaving compound shown in the following reaction formula A3.

<Reaction Formula A3>
However, in the reaction formula A3, one of X and Y is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these may be bonded to each other to form a ring.

  The partial structure represented by the general formula (A) modified to the polyphenylene raw material is represented by X—Y with an aromatic group (π electron conjugated site) represented by the general formula (B) by energy application. Is converted to

In the partial structure represented by the general formula (A), there are a plurality of isomers having different steric arrangements of substituents, all of which are converted into the specific partial structure represented by the general formula (B), The desorbing component remains the same.
X and Y, which are groups leaving from the compound represented by the general formula (A), are defined as a leaving substituent, and XY formed by combining them is defined as a leaving component. The desorbing component can take three states of solid, liquid, and gas, but considering removal to the outside of the system, the desorbing component is preferably liquid or gas, particularly preferably a gas at normal temperature, It becomes a gas at the temperature at which the elimination reaction is performed.

  The boiling point of the desorbing component is preferably 500 ° C. or lower at atmospheric pressure (1,013 hPa). Considering the ease of removal out of the system and the decomposition / sublimation temperature of the π-conjugated compound produced, 400 ° C. or lower is more preferable. Preferably, 300 degrees C or less is still more preferable.

In the following, in the general formula (A), X is an optionally substituted acyloxy group, and Y, Q ₁ , and Q ₆ are hydrogen atoms as an example. The following formula is shown. The conversion by the leaving reaction of the substituent leaving compound in the present invention is not limited to this.

<Reaction Formula A4>
In the above formula, R ³ is any one selected from a hydrogen atom, a halogen atom, an alkyl group, or an aryl group (hereinafter the same).

  In the case of the above example, by applying energy (heating), a carboxylic acid having an alkyl chain represented by the general formula (E) as a leaving component from the cyclohexadiene ring structure represented by the general formula (C). It is desorbed and converted into a specific compound having a structure containing a benzene ring represented by the general formula (D). When the heating temperature exceeds the boiling point of the carboxylic acid, the carboxylic acid quickly becomes a gas.

  Hereinafter, the mechanism by which the desorbing component is desorbed from the compound represented by the general formula (F) is outlined by the following reaction formula A5.

<Reaction Formula A5>
The elimination mechanism of the elimination component from the cyclohexadiene ring structure used in the present invention is the conversion from the general formula (F) to the general formula (H). In order to supplement the explanation, the elimination mechanism in the case of the cyclohexene ring [general formula (G)] is also shown.

As shown in the reaction formula A5, in the case of the cyclohexene ring represented by the general formula (F), by taking a transition state of a six-membered ring, the hydrogen atom on the β-carbon is transferred onto the oxygen atom of the carbonyl. The 1,5-rearrangement causes a concerted elimination reaction, whereby the carboxylic acid compound is eliminated and converted from a cyclohexene ring structure to a benzene ring structure represented by the general formula (H).
In the case of a compound having a cyclohexene structure having two acyloxy groups [the general formula (F)], the elimination reaction is considered to proceed in two stages. First, one carboxylic acid is eliminated and the general formula (G) The resulting cyclohexadiene ring structure is obtained.
At this time, the activation energy required to desorb one molecule of carboxylic acid from the disubstituted product represented by the general formula (F) is the same as that of the 1 substituted product represented by the general formula (G). Since it is sufficiently larger than that required for desorbing the molecule, the reaction proceeds rapidly in two steps and converted to the structure represented by the general formula (H).

Here, even when there are a plurality of stereoisomers due to the difference in the positional relationship between substituents (acyloxy group and hydrogen, etc.), the above reaction proceeds although the reaction rate is different.
The temperature reduction of the elimination reaction of the cyclohexadiene skeleton is not limited to the acyloxy group, and the same effect can be seen with an ether group or the like.
In the reaction formula A5, the extraction and transfer of hydrogen atoms on the β carbon are the first stage of the reaction. Therefore, the stronger the force of attracting hydrogen atoms of oxygen atoms, the more likely the reaction occurs. The degree varies depending on, for example, the alkyl chain on the acyloxy group side, and also varies by changing the oxygen atom to a chalcogen atom such as sulfur, selenium, tellurium, polonium or the like, which is also a group 16 element.

Examples of the energy applied (applied) for performing this elimination reaction include heat, light, and electromagnetic waves. From the viewpoint of reactivity, yield, and post-treatment, thermal energy or light energy is preferable, and in particular, thermal energy. Is preferred. Moreover, you may apply the said energy in presence of an acid or a base.
Usually, the elimination reaction depends on the structure of the functional group, but heating is often required from the viewpoint of reaction rate and reaction rate. The heating method for performing the elimination reaction includes a method of heating on a support, a method of heating in an oven, a method of irradiation with microwaves, a method of heating by converting light into heat using a laser, Although various methods, such as using a photothermal conversion layer, can be used, it is not limited to these.

Regarding the heating temperature for carrying out the elimination reaction, it is possible to use a range of room temperature (approximately 25 ° C.) to 500 ° C. The lower limit temperature is the upper limit temperature considering the thermal stability of the material and the boiling point of the elimination component. In view of energy efficiency, the abundance of unconverted molecules, decomposition of the compound after conversion, sublimation, etc., the range of 40 ° C. to 500 ° C. is preferable, and further consideration is given to the thermal stability during the synthesis of the substituent elimination compound. Then, the range of 60 degreeC-500 degreeC is more preferable, and 80 degreeC-400 degreeC is especially preferable.
Regarding the heating time, the higher the temperature, the shorter the reaction time, and the lower the temperature, the longer the time required for the elimination reaction. Further, although depending on the reactivity and amount of the substituent-eliminating compound, it is preferably 0.5 minutes to 120 minutes, more preferably 1 minute to 60 minutes, and particularly preferably 1 minute to 30 minutes.

  When light is used as an external stimulus, an infrared lamp, irradiation with light having a wavelength absorbed by the compound (for example, exposure to a wavelength of 405 nm or less), and the like may be used. At that time, a semiconductor laser may be used. For example, near-infrared laser light (usually laser light having a wavelength near 780 nm), visible laser light (usually laser light having a wavelength in the range of 630 nm to 680 nm), and laser light having a wavelength of 390 nm to 440 nm can be mentioned. Laser light having a wavelength of 390 nm to 440 nm is preferable, and semiconductor laser light having an oscillation wavelength in the range of 440 nm or less is preferably used. Among these, as a preferable light source, blue-violet semiconductor laser light having an oscillation wavelength in the range of 390 nm to 440 (more preferably 390 nm to 415 nm) and infrared semiconductor laser light having a central oscillation wavelength of 850 nm are used using an optical waveguide device. A blue-violet SHG laser beam having a center oscillation wavelength of 425 nm and a half wavelength can be given.

  In the elimination reaction of the leaving substituent, the acid or base acts as a catalyst, and conversion at a lower temperature is possible. The method of using these is not particularly limited, but it may be added as it is to the substituent-eliminating compound, or it may be dissolved in any solvent and added as a solution, or it is vaporized in the atmosphere. Heat treatment may be performed, a photoacid generator, a photobase generator, or the like may be added, and an acid and a base may be obtained in the system by light irradiation.

  Examples of the acid include hydrochloric acid, nitric acid, sulfuric acid, acetic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, 3,3,3-trifluoropropionic acid, formic acid, phosphoric acid, 2-butyloctanoic acid, and the like.

Examples of the photoacid generator include ionic generators such as sulfonium salts and iodonium salts and nonionic generators such as ionic photoacid generator imide sulfonate, oxime sulfonate, disulfonyldiazomethane, and nitrobenzyl sulfonate. be able to.
Examples of the base include hydroxides such as sodium hydroxide and potassium hydroxide, carbonates such as sodium hydrogen carbonate, sodium carbonate and potassium carbonate, amines such as triethylamine and pyridine, diazabicycloundecene, dia Amidines such as zabicyclononene can be used.
As the photobase generator, for example, carbamates, acyl oximes, ammonium salts and the like can be used.
Among these, it is preferable to carry out in an atmosphere of a volatile acid or base in view of the ease of removing the acid-base after the reaction outside the system.

  The atmosphere for the desorption reaction can be performed in the air with or without the above catalyst, but in order to eliminate side reactions such as oxidation and the influence of moisture, the system of further desorbed components is used. In order to promote the exclusion to the outside, it is preferable to carry out under an inert gas atmosphere or under reduced pressure.

  The method for forming an acyloxy group or the like to be a leaving substituent is not particularly limited and may be appropriately selected depending on the intended purpose. A later-described alcohol is reacted with a carboxylic acid chloride or a carboxylic acid anhydride or a halogen atom. In addition to the method of obtaining a carboxylic acid ester by the exchange reaction of carboxylic acid silver or carboxylic acid-quaternary ammonium salt, a method of reacting phosgene with an alcohol to obtain a carbonate ester, adding carbon disulfide to the alcohol, and then iodide Examples thereof include a method of obtaining xanthate by reacting alkyl, a method of obtaining amine oxide by reacting tertiary amine with hydrogen peroxide or carboxylic acid, and a method of obtaining selenoxide by reacting orthoselenocyanonitrobenzene with alcohol.

<Polyphenylene raw material polymer structure and polymer structure after removal of soluble groups>
The following are mentioned as a detailed illustration of a polyphenylene raw material. Incidentally, X and Y is a group defined as for _X 1 _{to X 3,} Y 1 to Y ₃ according to the general formula 1 and 2.

More specifically, the following structures are mentioned.

As described above, the exemplary compounds (1) to (11) are converted into the following specific structures by applying external energy.
A polymer film having a desired form can be obtained by applying and forming a polyphenylene polymer before conversion and applying external energy.

<Dehydrogenation process>
In the dehydrogenation process, hydrogen is eliminated radically or reductively and oxidatively by external energy. In addition, it has been reported that dehydrogenation is promoted using a catalyst or the like.
In the following reaction formulas A6 to A10, a specific structure of a carbon film having a specific width or shape obtained from a specific starting material is shown. Thus, the width and shape in the molecular minor axis direction vary depending on the size of the starting material. Incidentally, X and Y is a group defined as for _X 1 _{to X 3,} Y 1 to Y ₃ according to the general formula 1 and 2.

<Reaction Formula A6>

<Reaction Formula A7>

<Reaction Formula A8>

<Reaction Formula A9>

<Reaction Formula A10>

[Method of applying external energy]
Examples of the energy applied (applied) from the outside in order to remove the soluble group and perform the dehydrogenation reaction include heat, light, and electromagnetic waves. From the viewpoint of reactivity, yield, and post-treatment, thermal energy or light is used. Energy is preferred and thermal energy is particularly preferred. Moreover, you may apply the said energy in presence of an acid or a base.

As a heating method, there are various methods such as a method of heating on a support, a method of heating in an oven, a method of irradiation with microwaves, a method of converting light into heat using a laser, a method of using a photothermal conversion layer, etc. However, it is not limited to these methods.
Regarding the heating temperature, it is possible to use a range of room temperature (approximately 25 ° C.) to 2,000 ° C., and the lower limit temperature considers the thermal stability of the material and the boiling point of the desorbing component. Considering the substrate to be used, the abundance of unconverted molecules, the decomposition of the compound after conversion, sublimation, etc., the range of 40 ° C. to 1,000 ° C. is preferable, and further the thermal stability during the synthesis of the substituent elimination compound In consideration, the range of 60 ° C to 800 ° C is more preferable, and the range of 100 ° C to 650 ° C is more preferable.
Regarding the heating time, the higher the temperature, the shorter the reaction time, and the longer the temperature, the longer the reaction time. The time for removing the soluble group is preferably 0.5 minutes to 120 minutes, more preferably 1 minute to 60 minutes, and particularly preferably 1 minute to 30 minutes.
The time in the dehydrogenation reaction is preferably 0.5 minutes to 12 hours, more preferably 10 minutes to 2 hours, and particularly preferably 30 minutes to 1 hour.

When light is used as an external stimulus, an infrared lamp, irradiation with light having a wavelength absorbed by the compound (for example, exposure to a wavelength of 405 nm or less), and the like may be used. At that time, a semiconductor laser may be used. For example, near-infrared laser light (usually laser light having a wavelength near 780 nm), visible laser light (usually laser light having a wavelength in the range of 630 nm to 680 nm), and laser light having a wavelength of 390 nm to 440 nm can be mentioned. Among these, a laser beam having a wavelength of 390 nm to 440 nm is preferable, and a semiconductor laser beam having an oscillation wavelength in the range of 440 nm or less is preferably used. Among these, as a preferable light source, a blue-violet semiconductor laser beam having an oscillation wavelength in the range of 390 nm to 440 (more preferably 390 nm to 415 nm) and an infrared semiconductor laser beam having a central oscillation wavelength of 850 nm are half wavelength using an optical waveguide device. And blue-violet SHG laser light having a central oscillation wavelength of 425 nm.
The atmosphere when heating is preferably free of oxygen in the surroundings.

<Catalyst>
In order to promote the dehydrogenation reaction, it is preferable to use a catalyst. A catalyst such as that used in the graphene production method is preferably used. For example, a crystallized metal film can be used. There has been reported a method capable of epitaxially synthesizing the orientation of the six-membered ring of the carbon material, and examples thereof include crystal films of Au, Ag, Cu, Ni, Fe, Co, and the like. A crystal film such as HOPG is also preferably used. By adhering polyphenylene as a starting material to these, it functions as a catalyst. A method in which a crystal film is provided on a support substrate and polyphenylene is applied thereon is preferably used. Furthermore, a chemical catalyst can also be used. For example, by using an oxidizing agent, the Scholl reaction which is a dehydrogenation reaction can be promoted. For example, aluminum chloride, iron (III) chloride, copper (II) chloride, PIFA, boron trifluoride etherate, molybdenum chloride (V), lead tetraacetate and the like can be mentioned. These may be used by dissolving and dispersing together with the raw materials.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Example 1)
-Fabrication of carbon film-
A carbon film was prepared based on the following reaction formula.

(Process 1) Removal of dissolved group As a substrate on which the polyphenylene polymer 1 (degree of polymerization 25,000) is applied, a quartz substrate that has been subjected to ultrasonic cleaning using a cleaning liquid, ultrapure water, and isopropyl alcohol (IPA), respectively. Using.
A solution in which 5% by mass of polyphenylene polymer 1 was added to tetrahydrofuran (THF) was prepared, and a film was formed on the quartz substrate by spin coating. After the film formation, a polymer film in which soluble groups were removed from the polyphenylene polymer 1 was obtained by heating at 280 ° C. for 30 minutes in a nitrogen atmosphere.

(Process 2) Dehydrogenation reaction A polymer film formed on a quartz substrate in an argon atmosphere was immersed in a 20% by mass dichloromethane solution of iron (III) chloride for 30 minutes and then washed with methanol to obtain a carbon film. .

The TG and DSC measurement results of the polyphenylene polymer 1 used here are shown in FIG. Moreover, the result of the absorption spectrum of the polymer film (polymer) from which the polyphenylene polymer 1 (soluble polymer) and the soluble group were removed is shown in FIG. Moreover, the result of the absorption spectrum of a polymer film and a carbon film (graphene nanoribbon film) is shown in FIG. Further, it was confirmed that a carbon film was obtained by Raman spectroscopy of the thin film. Moreover, only carbon and hydrogen are observed from the elemental analysis results.
TG and DSC were measured using X-DSC7000 and TG / DTA7200 (manufactured by SII).
The absorption spectrum was measured using U3300 (manufactured by Hitachi, Ltd.).

  From the results of FIGS. 1 and 2, it can be seen that the removal of the dissolving group in (Process 1) is rapidly removed at 280 ° C., which indicates that the structure shown in the structural formula is obtained. Furthermore, the absorption wavelength is increased by adding iron (III) chloride, which is an oxidizing agent, supporting the formation of the graphene nanoribbon film.

(Example 2)
-Fabrication of carbon film-
A carbon film was prepared based on the following reaction formula.

As a substrate on which the polyphenylene polymer 2 (degree of polymerization 15,000) was applied, a substrate on which Au was deposited on a mica substrate and the Au (111) surface was exposed was used.
A solution in which 0.1% by mass of polyphenylene polymer 2 was added to THF was prepared, and a film was formed on the substrate by spin coating (1,000 rpm). After film formation, the film was placed in a vacuum chamber (back pressure 1.0 × 10 ⁻⁴ Pa) and heated with a ceramic heater. Each was heated at 300 ° C. and 450 ° C. for 1 hour.

Microscopic Raman spectroscopy of the obtained film was measured. The results are shown in FIG. In FIG. 4, 1 is a spin coat film of polyphenylene polymer 2, 2 is a spin coat film of polyphenylene polymer 2 vacuum-heated at 300 ° C., 3 is vacuum heat of polyphenylene polymer 2 at 450 ° C. It is a figure of microscopic Raman spectroscopy.
Micro-Raman spectroscopy was measured using Nanofinder (manufactured by Tokyo Instruments).
Moreover, in order to measure an absorption spectrum, the quartz substrate which ultrasonically cleaned using the washing | cleaning liquid, ultrapure water, and isopropyl alcohol (IPA) was used, respectively. A solution in which 1% by mass of the polyphenylene polymer 2 was added to tetrahydrofuran (THF) was prepared, and a film was formed on a quartz substrate by a spin coating method (1,000 rpm). After film formation, the film was placed in a vacuum chamber (back pressure 1.0 × 10 ⁻⁴ Pa) and heated with a ceramic heater. The sample was heated at 450 ° C. for 1 hour, and the change in absorption spectrum before and after heating was examined. The results are shown in FIG. In FIG. 5, 1 is a spin coat film of the polyphenylene polymer 2, and 2 is an absorption spectrum when the spin coat film of the polyphenylene polymer 2 is heated at 450 ° C. in a vacuum.

As shown by microscopic Raman spectroscopy, it was found that a G band (1,590 cm ⁻¹ ) and a D band (1,350 cm ⁻¹ ) were generated by vacuum heating at 300 ° C. or 450 ° C. This indicates that a graphene nanoribbon film is manufactured. Furthermore, even in the absorption spectrum of a quartz substrate heated (450 ° C) under the same conditions, the absorption is developed, the π conjugation is expanded, and the graphene nanoribbon film is formed more than the starting material. doing.
Thus, it became clear that a carbon thin film and a graphene nanoribbon can be easily produced by coating by using a polymer having a specific structure.

(Example 3)
<Elements using carbon thin film>
The mica Au substrate on which the carbon thin film produced in Example 2 was formed was immersed in an etching solution of an I ₂ / KI solution. The substrate was immersed in an etching solution for 10 minutes to release the carbon thin film. The released thin film was transferred by scooping with a silicon substrate (N-doped, 300 nm thick thermal oxide film). The transfer film was obtained by washing several times with pure water and methanol and vacuum drying.

The obtained transfer film is vacuum-deposited using a shadow mask (back pressure: 10 ⁻⁴ Pa, deposition rate: 1 Å / s to 2 Å / s, film thickness: 50 nm), thereby forming a source electrode and a drain electrode (Channel length 50 μm, channel width 2 mm). The organic semiconductor layer and the silicon oxide film at portions different from the source electrode and the drain electrode were scraped off, and a conductive paste (conductive paste, manufactured by Fujikura Kasei Co., Ltd.) was applied to the portion, and the solvent was dried. Using this portion, a voltage was applied to the silicon substrate as the gate electrode. Thus, an FET (Field Effect Transistor) element was produced.
The electrical characteristics of the obtained FET (field effect transistor) element were evaluated in the atmosphere using a semiconductor parameter analyzer 4156C (manufactured by Agilent).
As a result, a change in current between the source and drain was observed due to the modulation of the gate voltage. Furthermore, bipolar characteristics of P-type and N-type were confirmed. This proved effective as a transistor element.

Example 4
A gold electrode was formed in the same manner as in Example 3 on the transfer film obtained in the same manner as in Example 3. Nitric acid was spin-coated (1,500 rpm) between the formed gold electrodes and allowed to dry naturally. A conductive element was obtained by allowing to stand overnight at room temperature in an N ₂ atmosphere. When the sheet resistance is estimated by performing IV measurement (manufactured by Agilent, B1500A), it is about 1,000 Ω / □, and it was found that this element has conductivity.

As an aspect of this invention, it is as follows, for example.
<1> A carbon film including a polyphenylene polymer represented by the following general formula (I) and having a specific width or a specific shape.
<General formula (I)>
However, in said general formula (I), R < ₁ > -R < ₈ > is either selected from a hydrogen atom, a halogen atom, an alkyl group, and an aryl group, respectively. n represents the number of repetitions, and is an integer of 0 to 5. When n is 1 or more, R _{1 to} R ₈ may be the same as or different from each other. X is a group represented by any one of the following general formula 1 and the following general formula 2.
<General formula 1>
However, in General Formula 1, _one of X ₁ and Y ₁ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these may be bonded to each other to form a ring.
<General formula 2>
In General Formula 2, one of X ₂ , X ₃ , Y ₂ , and Y ₃ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these groups may be bonded to each other to form a ring.
<2> The carbon film according to <1>, wherein the carbon film is a graphene nanoribbon.
<3> A conductive element using the carbon film according to any one of <1> to <2>.
<4> A support substrate, a gate insulating layer on the substrate, a carbon film layer made of the carbon film according to any one of <1> to <2> on the gate insulating layer, and the carbon film layer And a second electrode spaced apart from the first electrode by the carbon layer. The carbon film element is characterized in that the first electrode is formed adjacent to the first electrode.

JP-T-2012-500199

PRL 99, 186801 (2007) Appl. Phys. Lett. 94, 082107 (2009) J. et al. AM. CHEM. SOC. 130, 4216 (2008) Nature 466, 470, (2010)

Claims (4)

A carbon film comprising a polyphenylene polymer represented by the following general formula (I) and having a specific width or a specific shape.
<General formula (I)>
However, in said general formula (I), R < ₁ > -R < ₈ > is either selected from a hydrogen atom, a halogen atom, an alkyl group, and an aryl group, respectively. n represents the number of repetitions, and is an integer of 0 to 5. When n is 1 or more, R _{1 to} R ₈ may be the same as or different from each other. X is a group represented by any one of the following general formula 1 and the following general formula 2.
<General formula 1>
However, in General Formula 1, _one of X ₁ and Y ₁ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these may be bonded to each other to form a ring.
<General formula 2>
In General Formula 2, one of X ₂ , X ₃ , Y ₂ , and Y ₃ is an optionally substituted ether group or acyloxy group having 1 or more carbon atoms, and the other is a hydrogen atom. Q ₁ to Q ₆ are each independently any one of a hydrogen atom, a halogen atom, and a monovalent organic group, and these groups may be bonded to each other to form a ring.   The carbon film according to claim 1, wherein the carbon film is a graphene nanoribbon.   A conductive element comprising the carbon film according to claim 1.   A support substrate, a gate insulating layer on the substrate, and a carbon film layer made of the carbon film according to claim 1 on the gate insulating layer, and formed adjacent to the carbon film layer. A carbon film element comprising: a first electrode; and a second electrode spaced apart from the first electrode by the carbon layer.