JP7182606B2 - High Performance Wide Bandgap Polymers for Organic Photovoltaics - Google Patents

Description

RELATING TO RELATED APPLICATIONS This application is related to U.S. Provisional Patent Application No. 65/538,362, filed July 28, 2017, entitled "High Performance Wide Bandgap Polymers for Organic Photovoltaics"; and PCT International Applications claiming benefit of and priority to US Patent Application No. 16/038,364, both of which are hereby incorporated by reference in their entirety.

STATEMENT REGARDING FEDERALLY FUNDED RESEARCH AND DEVELOPMENT None

The present invention relates to high performance wide-bandgap polymers for organic photovoltaics.

Solar energy using photovoltaics requires active semiconductor materials that convert light into electricity. Currently, silicon-based solar cells are the dominant technology due to their high power conversion efficiency. Recently, solar cells based on organic materials have shown interesting properties, especially their potentially low cost in materials and processing.

Organic photovoltaic cells have many potential advantages when compared to conventional silicon-based devices. Organic photovoltaic cells are light in weight, economical in materials, and can be attached to low-cost substrates such as flexible plastic foils. However, organic photovoltaic devices generally have relatively low power conversion efficiencies (ratio of incident photons to generated energy). This is thought to be due in part to the morphology of the active layer. The generated charge carriers must migrate to their respective electrodes before recombination or quenching occurs. The exciton diffusion length is generally much shorter than the optical absorption length, which can be compromised by the use of multiple or highly folded interfaces in thick, high-resistivity cells, or the low optical absorption efficiency in thin cells. A compromise must be sought.

The first reported use of quinoxaline dithiophene copolymers for organic photovoltaics was in 2008. One attractive feature of the quinoxalinedithiophene structure is that it can be easily functionalized with either the bromine atom or the trimethylstannyl group, thus allowing it to be copolymerized with a wide range of comonomers. is. A need exists to find quinoxaline dithiophene copolymers that can increase the open voltage.

を含んでなり；
反復単位Ｂ、ただし反復単位Ｂは

または

を含んでなり；および
少なくとも１つの任意の反復単位Ｄ、ここで反復単位Ｄはアリール基を含んでなる、
を含んでなるコポリマー。このコポリマーにおいて、Ｘ₁，Ｘ₂，Ｘ₃，およびＸ₄は：Ｈ，Ｃｌ，Ｆ，ＣＮ、アルキル、アルコキシ、エステル、ケトン、アミドおよびアリール基からなる群から独立して選択され、そしてＲ₁，Ｒ₂，Ｒ₃，Ｒ₄，Ｒ₅およびＲ₆は：Ｈ，Ｃｌ，Ｆ，ＣＮ，アルキル、アルコキシ、アルキルチオ、エステル、ケトンおよびアリール基からなる群から独立して選択される。 Repeating unit A, where repeating unit A is

comprising;
Repeating unit B, where repeating unit B is

or

and at least one optional repeating unit D, wherein repeating unit D comprises an aryl group.
A copolymer comprising In this copolymer, X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups; ₁ , _R2 , _R3 , _R4 , _R5 and _R6 are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups.

を含んでなり；
反復単位Ｈ、ただし反復単位Ｈは

を含んでなり；
任意の反復単位Ｊ、ただし反復単位Ｊは

を含んでなり；および
反復単位Ｋ、ただし反復単位Ｋは

を含んでなる、
を含んでなるコポリマー。このコポリマーにおいて、Ｘ₁、Ｘ₂、Ｘ₃およびＸ₄は：Ｈ，Ｃｌ，Ｆ，ＣＮ、アルキル、アルコキシ、エステル、ケトン、アミドおよびアリール基から独立して選択され；Ｒ₁、Ｒ₂，Ｒ₃およびＲ₄は：Ｈ，Ｃｌ，Ｆ，ＣＮ、アルキル、アルコキシ、アルキルチオ、エステル、ケトンおよびアリール基からなる群から独立して選択され；そしてＤはアリール基を含んでなる。 Repeating unit E, where repeating unit E is

comprising;
Repeating unit H, where repeating unit H is

comprising;
Any repeating unit J, where repeating unit J is

and repeat unit K, where repeat unit K is

comprising
A copolymer comprising In this copolymer, X ₁ , X ₂ , X ₃ and X ₄ are independently selected from: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups; R ₁ , R ₂ , R ₃ and R ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups; and D comprises an aryl group.

を含んでなり；
反復単位Ｇ、ただし反復単位Ｇは

を含んでなり
任意の反復単位Ｊ、ただし反復単位Ｊは

を含んでなり；
および
反復単位Ｋ、ただし反復単位Ｋは

を含んでなる、
を含んでなるコポリマー。このコポリマーにおいて、Ｘ₁、Ｘ₂、Ｘ₃およびＸ₄は：Ｈ，Ｃｌ，Ｆ，ＣＮ、アルキル、アルコキシ、エステル、ケトン、アミドおよびアリール基から独立して選択され；Ｒ₅およびＲ₆は：Ｈ，Ｃｌ，Ｆ，ＣＮ、アルキル、アルコキシ、アルキルチオ、エステル、ケトンおよびアリール基からなる群から独立して選択され；そしてＤはアリール基を含んでなる。 Repeating unit F, where repeating unit F is

comprising;
Repeating unit G, where repeating unit G is

any repeating unit J, where the repeating unit J is

comprising;
and repeat unit K, where repeat unit K is

comprising
A copolymer comprising In this copolymer, X ₁ , X ₂ , X ₃ and X ₄ are independently selected from: H, Cl, F _, CN, alkyl, alkoxy, _ester , ketone, amide and aryl groups; : H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups; and D comprises an aryl group.

A more complete understanding of the invention and its advantages can be obtained by referring to the following description in conjunction with the accompanying drawings.
1 represents the structure of a conventional device and the structure of the device of the present invention; Represents the formation of functionalized QDT monomers. 1 represents the ¹ H NMR spectrum of Compound 1. FIG. 1 represents the ¹ H NMR spectrum of compound 2. FIG. 1 represents the ¹ H NMR spectrum of compound 3. FIG. 1 represents the ¹ H NMR spectrum of compound 4. FIG. ¹ H NMR spectrum of QDT-Br. Represents the ¹ H NMR spectrum of QDT-SnMe ₃ . FIG. 3 depicts the NMR spectrum of the first step forming the unsymmetrical bithiophene monomer. FIG. 3 depicts the NMR spectrum of the second step forming the unsymmetrical bithiophene monomer. Figure 3 depicts the NMR spectrum of the third step forming the unsymmetrical bithiophene monomer. 1 represents the NMR spectrum of an unsymmetrical bithiophene monomer. Represents different methods of forming benzodithiophenes. Represents the UV-visible absorption of various polymers.

DETAILED DESCRIPTION We now turn to a detailed description of the preferred configuration(s) of the invention, that the features and concepts of the invention may be implemented with other configurations, and that the scope of the invention may be as described or specifically described. It should be understood that it is not limited to the described embodiments. It is intended that the scope of the invention be limited only by the claims that follow.

As used herein, "alkyl" refers to an aliphatic hydrocarbon chain. In one aspect, the aliphatic hydrocarbon chain is 1 to about 100 carbon atoms, preferably 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and is methyl, ethyl, n -including straight and branched chains such as propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, neo-pentyl, n-hexyl and isohexyl. In this application, alkyl groups can include the possibility of substituted and unsubstituted alkyl groups.

As used herein, "alkoxy" refers to the group RO-, where R is an alkyl group of 1 to 100 carbon atoms. In this application, alkoxy groups can include the possibility of substituted and unsubstituted alkoxy groups.

As used herein, an “aryl” is an optionally substituted group having from about 5 to about 50 carbon atoms (and all combinations and subcombinations of ranges and specific numbers of carbon atoms therein). mono-, di-, tri-, or other polycyclic aromatic ring systems of about 6 to about 10 carbon atoms are preferred. Non-limiting examples include, for example, phenyl, naphthyl, anthracenyl, and phenanthrenyl. Aryl groups can be optionally substituted with one or more Rx. In this application, aryl groups can include the possibilities of substituted aryl groups, bridged aryl groups and fused aryl groups.

As used herein, "ester" refers to a group of formula -COOR, where R represents an "alkyl", "aryl", "heterocycloalkyl" or "heteroaryl" moiety, or as defined above. represents the permuted

As used herein, "ketone" refers to an organic compound having a carbonyl group attached to a carbon atom such as -C(O)Rx, where Rx is an alkyl, aryl, cycloalkyl, cycloalkenyl or hetero can be a ring.

As used herein, "amido" represents a group of formula "-C(O)NR ^x R ^y ", where R ^x and R ^y are the same or independently H, alkyl, aryl , cycloalkyl, cycloalkenyl or heterocycle.

The following examples of specific embodiments of the invention are given. Each example is provided by way of explanation of the invention, one of many aspects of the invention, and the following examples should not be read as limiting or defining the scope of the invention.

Device structure When used as a photovoltaic power generation device, the structure may be a device with a conventional structure, but in other respects it may be a reverse structure device. Devices of conventional construction generally consist of a multilayer structure comprising a transparent anode as a substrate for collecting positive charges (holes) and a cathode for collecting negative charges (electrons), and a photoactive layer consisting of two layers. sandwiched between the electrodes. An additional charge transport interlayer is inserted between the active layer and the electrode to facilitate hole and electron transport. Each charge transfer layer can consist of one or more layers. The inverse device has the same multilayer structure as the conventionally constructed device, but uses a transparent cathode as the substrate for collecting electrons and a cathode for collecting holes. The inverse device also has a photoactive layer and an additional charge transport layer sandwiched between two electrodes. FIG. 1 represents the structure of a conventional device and the structure of an inverse device.

である。反復単位Ａにおいて、Ｘ₁、Ｘ₂、Ｘ₃およびＸ₄は、Ｈ，Ｃｌ，Ｆ，ＣＮ、アルキル、アルコキシ、エステル、ケトン、アミドおよびアリール基から独立して選択される。 Repeating unit A:
In one aspect, repeating unit A is a quinoxaline dithiophene (QDT) monomer

is. In repeating unit A, X ₁ , X ₂ , X ₃ and X ₄ are independently selected from H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups.

The QDT monomer can be functionalized with various halogen atoms and stannanes to prepare it for the final polymerization reaction. In one non-limiting example, the formation of functionalized QDT monomers is illustrated in FIG.

As shown in FIG. 2, the formation of compound 1 was accomplished by mixing 2-ethylhexyl bromide (17.3 mL, 0.097 mol) with freshly ground magnesium (2.61 g, 0.107 mol) in dry tetrahydrofuran (250 mL). Begin by forming a 2-ethylhexylmagnesium bromide solution prepared by adding dropwise to the mixture. Once the addition was complete, the 2-ethylhexylmagnesium bromide solution was stirred at room temperature for about 2 hours. After some time a solution of LiBr (17 g, 0.196 mol) in dry tetrahydrofuran (100 mL) was added to a solution of CuBr in dry tetrahydrofuran (150 mL). The CuBr/LiBr/tetrahydrofuran solution was then cooled to -78°C and the 2-ethylhexylmagnesium bromide solution was added dropwise. Once the transfer was complete oxalyl chloride (3.33 mL, 0.039 mol) was added. The reaction was gradually warmed to room temperature and stirred for about 18 hours. The reaction was quenched by pouring the reaction into saturated aqueous NH ₄ Cl (500 mL). The tetrahydrofuran layer was then removed and the aqueous layer was extracted with ethyl ether. The combined organic layers were dried, filtered and concentrated. The crude product was diluted with hexanes and loaded onto a 340 g Biotage cartridge, then purified using a 5-20% dichloromethane/hexanes gradient. Fractions containing product were concentrated to give a yellow oil (1.63 g; 15% yield). The ¹ H NMR spectrum of compound 1 is presented in FIG.

Formation of compound 2 was formed by placing FeCl ₃ (10.9 g, 67.481 mmol) in an oven-dried Schlenk flask at high temperature, then applying vacuum and backfilling with argon (3×). Dry dichloromethane (140 mL) was added to the flask via cannula, followed by 3,3'-thenyl (5 g, 22.494 mmol) in one portion. The reaction was stirred at room temperature under argon. After about 2 hours, the reaction was quenched with water (~100 mL) and stirred. The solvent was removed via rotovap and the solid was suspended in water and left at room temperature overnight. The solids were filtered and washed with water, then air dried and washed with diethyl ether (~200 mL). A black solid (4.5 g, 91% yield) was then collected by filtration, washed with acetonitrile and dried under vacuum. The ¹ H NMR spectrum of compound 2 is presented in FIG.

Formation of compound 3 involved compound 2 (2 g, 0.009 mol), 200-proof ethanol (100 mL), and hydroxylamine hydrochloride (1.577 g, 0.023 mol) in a 250 mL round-bottomed flask under argon. Added downstream. The flask was then fitted with a condenser and argon inlet and the reaction was heated to reflux for 22 hours. The reaction is then cooled to room temperature and palladium on carbon (10%, 200 mg) is added. An addition funnel was added to the top of the condenser and the funnel was filled with a solution of hydrazine monohydrate (15 mL) in ethanol (25 mL). After heating the reaction to 65° C., the hydrazine solution was added dropwise. Once the addition was complete, the reaction was heated at 85° C. for 20 hours. The reaction mixture was cooled and then filtered through filter paper and the residue was washed with ethanol. The solvent was removed straight down and the resulting solid was dispersed in water and filtered. The solid was washed with water and cold ethanol and transferred to a flask and left under vacuum for several hours. The product obtained was a brown solid (1.75 g, 87% yield). ¹ H NMR of compound 3 is shown in FIG.

Formation of Compound 4 is formed by combining Compound 3 (1.6 g, 7.262 mmol) and Compound 1 (2.154 g, 7.625 mmol) in a 50 mL Schlenk flask. The flask was evacuated and backfilled with argon, then acetic acid was added and the reaction was heated at 100° C. for 16 hours. The reaction mixture was cooled to room temperature, then diluted with water and transferred to a separatory funnel. The aqueous layer was extracted with dichloromethane. The aqueous layer was neutralized _{with Na2CO3} and extracted with dichloromethane. The combined organic extracts were dried ( _MgSO4 ), filtered and concentrated. The crude product was dissolved in dichloromethane, adsorbed onto silica gel and purified on a 100 g Biotage cartridge using a 0-60% dichloromethane/hexanes gradient. Fractions containing the desired product were concentrated to give a yellow solid (1.55 g, 46% yield). ^{A 1} H NMR spectrum of compound 4 is shown in FIG.

Formation of QDT-Br was accomplished by dissolving compound 4 (400 mg, 0.857 mmol) in tetrahydrofuran (9 mL) followed by N-bromosuccinimide (0.32 g, 0.002 mol) and stirring at room temperature for 16 h. Formed by stirring. The reaction mixture was poured into water and extracted with dichloromethane (3x). The combined organic extracts were dried ( _MgSO4 ), filtered and concentrated. The crude product was dissolved in dichloromethane, adsorbed onto silica gel and purified on a 100 g Biotage column using a 0-50% dichloromethane/hexanes gradient. Fractions from the main peak were concentrated to give a yellow solid (440 mg, 82% yield). A ¹ H NMR spectrum of QDT-Br is shown in FIG.

Formation of QDT-SnMe ₃ was formed by combining compound 4 (1.15 g, 2.464 mmol) and dry tetrahydrofuran (25 mL) in an argon-filled Schlenk flask. The solution was cooled to −78° C. and then treated dropwise with a solution of n-BuLi (2.5 M in hexanes, 2.4 mL, 5.913 mmol). The reaction was stirred at −78° C. for 1 hour, followed by stirring at room temperature for 1.5 hours. The reaction mixture was cooled again to -78°C and slowly treated with SnMe ₃ Cl solution (1M in hexanes, 7.392 mL, 7.392 mol). The reaction was slowly warmed to room temperature and stirred for 16 hours. The reaction mixture was poured into water and extracted with dichloromethane (3x). The combined organic extracts were washed with water, dried ( _MgSO4 ), filtered and concentrated to give a yellow oil. Attempted recrystallization from isopropanol, methanol and ethanol, but the material was always oiled out. The resulting greenish oil (850 mg, 44% yield) was used without further purification. ^{A 1} H NMR spectrum of QDT-SnMe ₃ is shown in FIG.

またはベンゾジチオフェン

である。反復単位Ｂにおいて、Ｒ₁，Ｒ₂，Ｒ₃，Ｒ₄，Ｒ₅およびＲ₆はＣｌ，Ｆ，ＣＮ、アルキル、アルコキシ、アルキルチオ、エステル、ケトンおよびアリール基からなる群から独立して選択される。 Repeating unit B:
In one aspect, repeating unit B is an unsymmetrical bithiophene monomer

or benzodithiophene

is. In repeating unit B, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently selected from the group consisting of Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups. be.

In a non-limiting example, the formation of an unsymmetrical bithiophene monomer is described below. Formation of the asymmetric bithiophene monomer can begin with the synthesis of 3-(2-hexyldecyl)thiophene. To a 3-necked 500 mL flask was added magnesium turnings (3.184 g, 0.131 mol). 7-(bromomethyl)pentadecane (20 g, 0.066 mol) was added to the addition funnel. The system was evacuated and backfilled with argon three times. After adding a small amount of iodine, 10 mL of anhydrous THF was added to the flask and 90 mL of anhydrous THF was added to the addition funnel. The reaction was initiated by first adding 10 mL of 7-(bromomethyl)pentadecane solution followed by heating to reflux. After refluxing for 2 hours, it was cooled to room temperature. In a separate 100 mL Schlenk flask, 3-bromothiophene (10.68 g, 0.066 mol) and Ni(dppp)Cl ₂ (1.78 g, 3.3 mmol) were solubilized in 100 mL anhydrous THF. , then slowly transferred to the reaction mixture. The reaction mixture was further perfused at 70° C. for 3 hours and then stirred overnight at room temperature. The reaction was stopped by pouring over crushed ice. Cold aqueous HCl was added to dissolve the solids. The product was extracted with hexane and dried over anhydrous _MgSO4 . The crude product was purified by column chromatography using hexane as an eluent, and then distilled under reduced pressure to obtain a colorless transparent liquid as the product (6.80 g, 33.6%). NMR spectrum is shown in FIG.

The second step in forming the asymmetric bithiophene monomer can begin with the synthesis of 2-bromo-3-(2-hexyldecyl)thiophene. 3-(2-Hexyldecyl)thiophene (5 g, 0.016 mol) was added to a 200 mL Schlenk flask. The system was evacuated and backfilled with argon three times before adding 200 mL of anhydrous THF. After cooling the solution to −78° C., N-bromosuccinimide (2.884 g, 0.016 mol) was added in portions, protected from light. The reaction mixture was stirred overnight. The reaction was stopped by adding aqueous Na ₂ CO ₃ solution. The product was extracted with hexane, then dried over anhydrous _MgSO4 and the solvent was removed. The product was further purified on a silica gel column with hexane as eluent and a colorless liquid (5.48 g, 87.3% yield) was obtained after drying in vacuum. NMR spectrum is shown in FIG.

The third step in forming the asymmetric bithiophene monomer can begin with the synthesis of 3-(2-hexyldecyl)-2,2'-bithiophene. 2-bromo-3-(2-hexyldecyl)thiophene (5.68 g, 0.015 mol), tributyl(thiophen-2-yl)stannane (5.471 g, 0.015 mol) and Pd ₂ (dba) ₃ (0.268 g, 0.293 mmol), P(o-tol) ₃ (0.357 g, 1.173 mmol) were combined in a 200 mL Schlenk flask. The system was evacuated and backfilled with argon three times before injecting 100 mL of anhydrous toluene. The reaction was heated at 105° C. for 24 hours and cooled to room temperature. The toluene solvent was removed on a rotary evaporator and the resulting residue was purified on a silica gel column using pure hexane as eluent. Vacuum distillation of the crude product gave a colorless liquid as the final product (4.34 g, 74.1% yield). NMR spectrum is shown in FIG.

The final step in the formation of the asymmetric bithiophene monomer begins with the synthesis of (3-(2-hexyldecyl)-[2,2'-bithiophene]-5,5'-diyl)bis(trimethylstannane) (HDTT). be able to. 3-(2-hexyldecyl)-2-(thiophen-2-yl)thiophene (4.15 g, 10.6 mmol) was added to a 200 mL Schlenk flask. The system was evacuated and backfilled with argon three times before adding 100 mL of anhydrous THF. After cooling the solution to −78° C., n-butyllithium (9.35 mL, 2.5 M in THF, 23.4 mmol) was added dropwise. The reaction was stirred at room temperature for 1.5 hours before being cooled back to -78°C. A solution of trimethyltin chloride (26.56 mL, 1.0 M in THF, 26.556 mmol) was added dropwise. The resulting mixture was stirred overnight. 50 mL of water was added. The product was extracted with hexane. The organic layer was washed with water three times and then dried over _{anhydrous Na2SO4} . Solvent was removed, then dissolved in hexane and washed twice with methanol. After removing the solvent, a green liquid was obtained as the product (5.05 g, 66.4% yield). NMR spectrum is shown in FIG.

In a non-limiting example, FIG. 13 depicts different methods of forming benzodithiophenes. A conventional method is shown in FIG. 13, but the invention is not limited to any one specific method of forming benzodithiophenes. (ii) diethylamine; (iii) n-butyllithium, then water; (iv) alkynelithium; (v) _SnCl2 ,HCl; (vi) Pd/C,H2; vii) Zn, NaOH, H ₂ O; (viii) bromoalkane, TBAB; (ix) aromatic lithium; (x) n-butyllithium, chlorotrimethylstannane or 2-isopropoxy-4,4,5,5 -tetramethyl-1,3,2-dioxaborane; and (xi) a Pd catalyst.

any repeating unit D
In one aspect, at least one optional repeating unit D has from about 5 to about 50 carbon atoms (and all combinations and subcombinations of ranges and specific numbers of carbon atoms therein), Refers to optionally substituted mono-, di-, tri-, or other polycyclic aromatic ring systems of from about 6 to about 20 carbon atoms are preferred. Non-limiting examples include, for example, phenyl, naphthyl, anthracenyl, and phenanthrenyl. Aryl groups can be optionally substituted with one or more Rx. In this application, aryl groups can include the possibilities of substituted aryl groups, bridged aryl groups and fused aryl groups. Although it is possible for only one repeat unit D to be present in the copolymer, it is also envisioned that multiple repeat units D may be present in the copolymer.

およびそれらの組み合わせからなることができ、ここでＲ’Ｒ’’、Ｒ’’’およびＲ’’’’は：Ｈ、Ｃｌ、Ｆ、ＣＮ、アルキル、アルコキシ、アルキルチオ、エステル、ケトンおよびアリール基から独立して選択される。別の態様では、アリール基は３，３’ジフルオロ－２，２’－ビチオフェンである。 In one aspect, the aryl group is:

and combinations thereof, wherein R'R'', R''' and R'''' are: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups is independently selected from In another aspect, the aryl group is 3,3'difluoro-2,2'-bithiophene.

Copolymer Repeating unit A, repeating unit B and optional repeating unit D, when taken together, yield a copolymer. Copolymers can be regio-random or regio-regular. It is envisioned that the copolymers can be used as photovoltaic materials. It is also envisioned that the copolymers can be used as active layers in electronic devices. In one aspect, the number of repeating units A, B and B can range from about 3 to about 10,000 in the copolymer. In another aspect, the copolymer can form a polymer bandgap greater than 1.8 eV.

として反復単位ＡおよびＢの組み合わせを含むことができる。 In some embodiments, the copolymer comprises repeating unit E:

can include a combination of repeat units A and B as

として反復単位ＡおよびＢの組み合わせを含むことができる。 In some embodiments, the copolymer comprises repeating unit F:

can include a combination of repeat units A and B as

として反復単位ＡおよびＤを含むことができる。 In some aspects, the copolymer comprises repeating unit G:

can include repeat units A and D as

として反復単位ＡおよびＤを含むことができる。 In some aspects, the copolymer comprises repeating unit H:

can include repeat units A and D as

In one aspect, the amount of repeating unit A in the copolymer can range from 1% to 99% by weight.

In one aspect, the amount of repeat unit B in the copolymer can range from 1% to 99% by weight.

In one aspect, the amount of repeat unit D in the copolymer can range from 0% to 99% by weight.

Anodes When used in organic photovoltaic devices, the copolymers can be used in conjunction with anodes. The anode for the organic photovoltaic device can be any conventionally known anode capable of operating as an organic photovoltaic device. Examples _of anodes _that can be used include: indium tin oxide, aluminum, carbon, graphite, graphene, PEDOT:PSS, copper, _metal nanowires, _Zn99InOx , _{Zn98In2Ox , Zn97In3Ox} , Zn _{. 95Mg5Ox , Zn90Mg10Ox , and Zn85Mg15Ox . _ _}

Cathodes When used in organic photovoltaic devices, the copolymers can be used in conjunction with cathodes. The cathode for the organic photovoltaic device can be any conventionally known cathode capable of operating as an organic photovoltaic device. Examples of cathodes that can be used include: indium tin oxide, carbon, graphite, graphene, PEDOT:PSS, copper, silver, gold, metal nanowires.

Electron Transport Layer For use in organic photovoltaic devices, the copolymer can be attached to the electron transport layer. Commercially available electron transfer layers optimized for organic photovoltaic devices can be used. In one aspect, the electron transport layer can comprise (AO _x ) _y BO _(1-y) . In this embodiment, (AO _x ) _y and BO _(1-y) are metal oxides. A and B can be different metals chosen to achieve an ideal electron transport layer. In one aspect, A can be aluminum, indium, zinc, tin, copper, nickel, cobalt, iron, ruthenium, rhodium, osmium, tungsten, magnesium, indium, vanadium, titanium and molybdenum.

In one aspect, B can be aluminum, indium, zinc, tin, copper, nickel, cobalt, iron, ruthenium, rhodium, osmium, tungsten, vanadium, titanium and molybdenum.

Examples of ( _AOx ) _{yBO (1-y)} include: ( _SnOx ) _{yZnO (1-y)} , ( _AlOx ) _{yZnO (1-y)} , ( _{AlOx ) yInOz(1- y)} , ( _AlOx ) _{ySnOz (1-y)} , ( _AlOx ) _{yCuOz (1-y) ,} ( _AlOx ) _{yWOz (1-y)} , (InOx ₎ yZnO _{(1 -y)} , ( _InOx ) _{ySnOz (1-y)} , ( _InOx ) _{yNiOz (1-y)} , ( _ZnOx ) _{yCuOz (1-y)} , ( _{ZnOx ) yNiOz (1-y)} , ( _ZnOx ) _{yFeOz (1-y)} , ( _WOx ) _{yVOz (1-y)} , ( _WOx ) _{yTiOz (1-y)} and ( _WOx ) _y Contains _MoOz(1-y) .

および［６，６］－フェニル－Ｃ₆₀－ブチリック－Ｎ－２－トリメチルアンモニウムエチルエステルヨージドを含む。 In an alternative embodiment, various fullerene dopants can be combined with (AO _x ) _y BO _(1-y) to create electron transport layers for organic photovoltaic devices. Examples of fullerene dopants that can be combined include:

and [6,6]-phenyl-C ₆₀ -butyric-N-2-trimethylammonium ethyl ester iodide.

の態様では、Ｒ’はＮ、Ｏ、Ｓ、ＣまたはＢのいずれかから選択することができる。他の態様では、Ｒ”はアルキル鎖または置換アルキル鎖であることができる。置換アルキル鎖の置換基の例には、ハロゲン、Ｎ、Ｂｒ、Ｏ、Ｓｉ，またはＳを含む。１つの態様では、Ｒ”は

から選択することができる。使用することができる他のフラーレンドーパントの他の例には：［６，６］－フェニル－Ｃ₆₀－ブチリック－Ｎ－（２－アミノエチル）アセトアミド、［６，６］－フェニル－Ｃ₆₀－ブチリック－Ｎ－トリエチレングリコールエステル、および［６，６］－フェニル－Ｃ₆₀－ブチリック－Ｎ－２－ジメチルアミノエチルエステルを含む。

In the embodiment R' can be selected from any of N, O, S, C or B. In other aspects, R″ can be an alkyl chain or a substituted alkyl chain. Examples of substituents for substituted alkyl chains include halogen, N, Br, O, Si, or S. In one aspect, , R” is

You can choose from Other examples of other fullerene dopants that can be used include: [6,6]-phenyl-C ₆₀ -butyric-N-(2-aminoethyl)acetamide, [6,6]-phenyl-C ₆₀ - butyric-N-triethylene glycol ester, and [6,6]-phenyl-C ₆₀ -butyric-N-2-dimethylaminoethyl ester.

Synthetic sample A of polymer:
QDT-Br (53.53 mg, 0.086 mmol), (3-(2-hexyldecyl)-[2,2′-bithiophene]-5,5′-diyl)bis(trimethylstannane) in a Schlenk flask. ) (61.40 mg, 0.086 mmol), P(o-tol) ₃ (4.17 mg, 0.014 mmol), and Pd ₂ dba ₃ (3.14 mg, 0.003 mmol) were combined, followed by 2 Time degassed. After refilling with argon, dry chlorobenzene (1.7 mL) was added and the reaction mixture was passed through three freeze-pump-thaw cycles using liquid nitrogen to freeze the solution. I degassed. The solution was then heated to 125° C. and stirred under an argon atmosphere for 21 hours. The reaction mixture was cooled to room temperature, poured into methanol (50 mL) and the polymer was collected by filtration. The polymer was purified by Soxhlet extraction and washed sequentially with acetone and hexane. This copolymer, sample A, was recovered from the hexane fraction (62 mg, 82% yield).

Sample B:
In a Schlenk flask, QDT-Br (55.42 mg, 0.089 mmol), stannane, 1,1′-[3,3′″-bis(2-octyldodecyl)[2,2′:5′, 2″: 5″,2′″-Quaterthiophene]-5,5′″-diyl]bis[1,1,1-trimethyl (108.00 mg, 0.089 mmol), P(o -tol) ₃ (4.32 mg, 0.014 mmol) and Pd ₂ dba ₃ (3.25 mg, 0.003 mmol) were combined and then degassed for 2 hours. After refilling with argon, dry dichlorobenzene (1.8 mL) was added and the reaction mixture was degassed via three freeze degas cycles using liquid nitrogen to freeze the solution. The solution was then heated to 125° C. and stirred under an argon atmosphere for 21 hours. The reaction mixture was cooled to room temperature, poured into methanol (50 mL) and the polymer was collected by filtration. The polymer was purified by Soxhlet extraction and washed sequentially with acetone and hexane. This copolymer, sample B, was recovered from the hexane fraction (89 mg, 72% yield).

Sample C:
In a Schlenk flask, QDT-Br (50.00 mg, 0.080 mmol), stannane, 1,1′-naphtho[1,2-b:5,6-b′]dithiophene-2,7-
diylbis[1,1,1-trimethyl (45.31 mg, 0.080 mmol), P(o-tol) ₃ (3.90 mg, 0.013 mmol) and Pd ₂ dba ₃ (2.93 mg, 0.003 millimoles) were combined and then degassed for 2 hours. After refilling with argon, dry dichlorobenzene (1.6 mL) was added and the reaction mixture was degassed via three freeze degas cycles using liquid nitrogen to freeze the solution. The solution was then heated to 125° C. and stirred under an argon atmosphere for 23 hours. The reaction mixture was cooled to room temperature, poured into methanol (50 mL) and the polymer was collected by filtration. The polymer was purified by Soxhlet extraction and washed sequentially with acetone, hexane and chloroform. This copolymer, sample C, was recovered from the chloroform fraction (22 mg, 37% yield).

Sample D:
In a Schlenk flask, QDT-SnMe ₃ (40.00 mg, 0.050 mmol), 2,1,3-benzothiadiazole, 4,7-bis[5-bromo-4-(2-octyldodecyl)-2- thienyl]-5,6-difluoro (45.31 mg, 0.080 mmol), P(o-tol) ₃ (2.46 mg, 0.008 mmol) and Pd ₂ dba ₃ (1.85 mg, 0.002 mmol) ) were combined and then degassed for 2 hours. After refilling with argon, dry chlorobenzene (1.0 mL) was added and the reaction mixture was degassed via three freeze degas cycles using liquid nitrogen to freeze the solution. The solution was then heated to 125° C. and stirred under an argon atmosphere for 23 hours. The reaction mixture was cooled to room temperature, poured into methanol (50 mL) and the polymer was collected by filtration. The polymer was purified by Soxhlet extraction and washed sequentially with acetone and hexane. This copolymer, sample D, was recovered from the hexane fraction (55 mg, 78% yield).

Sample E:
QDT-Br (100.3 mg, 0.161 mmol), (3-(2-hexyldecyl)-[2,2′-bithiophene]-5,5′-diyl)bis(trimethylstannane) in a Schlenk flask. ) (57.5 mg, 0.08 mmol), stannane, 1,1′-[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4, 5-b′]dithiophene-2,6-diyl]bis[1,1,1-trimethyl (72.6 mg, 0.08 mmol), P(o-tol) ₃ (7.8 mg, 0.026 mmol) , and Pd ₂ dba ₃ (5.9 m, 0.006 mmol) were combined and then degassed for 1 hour. After refilling with argon, dry chlorobenzene (3.2 mL) was added and the reaction mixture was degassed via three freeze degas cycles using liquid nitrogen to freeze the solution. The solution was then heated to 130° C. and stirred for 24 hours under an argon atmosphere. The reaction mixture was cooled to room temperature, poured into methanol (50 mL) and the polymer was collected by filtration. The polymer was purified by Soxhlet extraction and washed sequentially with acetone, hexane and chloroform. This copolymer, sample E, was recovered from the chloroform fraction (130 mg, 85% yield).

Sample F:
QDT-Br (100.1 mg, 0.160 mmol), (3-(2-hexyldecyl)-[2,2′-bithiophene]-5,5′-diyl)bis(trimethylstannane) in a Schlenk flask. ) (80.4 mg, 0.11 mmol), stannane, 1,1′-(3,3′-difluoro[2,2′-bithiophene]-5,5′-diyl)bis[1,1,1- Trimethyl (25.4 mg, 0.05 mmol), P(o-tol) ₃ (7.8 mg, 0.026 mmol) and Pd ₂ dba ₃ (5.9 mg, 0.006 mmol) were combined and then stirred for 1 hour. Degassed. After refilling with argon, dry chlorobenzene (3.2 mL) was added and the reaction mixture was degassed via three freeze degas cycles using liquid nitrogen to freeze the solution. The solution was then heated to 130° C. and stirred for 24 hours under an argon atmosphere. The reaction mixture was cooled to room temperature, poured into methanol (50 mL) and the polymer was collected by filtration. The polymer was purified by Soxhlet extraction and washed sequentially with acetone, hexane and chloroform. This copolymer, sample F, was recovered from the chloroform fraction (100 mg, 99% yield).

Fabrication of Organic Photovoltaic Devices Zinc/Tin Oxide (ZTO): A sol-gel solution of phenyl-C60-butyric-N-(2-hydroxyethyl)acetamide (PCBNOH) was prepared as zinc acetate dihydrate or tin acetate. (II) was prepared by dissolving in 2-methoxyethanol and ethanolamine. Specifically, the ZTO:PCBNOH sol-gel electron transfer layer solution consisted of 3.98 g Zn(OAc) ₂ , 398 mg Sn(OAc) ₂ and 20.0 mg PCBNOH in 54 mL 2-methoxyethanol. Prepared by mixing while adding 996 μL of ethanolamine. The solution was then further diluted to 65% by adding 2-methoxyethanol and stirred for at least 1 hour before spin casting onto an indium tin oxide substrate to form an electron transfer layer.

Polymers and Acceptors, PC ₇₀ BM, and Non-Fullerene Acceptor 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis (4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene (ITIC) 1:1 It was dissolved in chlorobenzene at a ratio of .2 at a concentration of 26 mg/mL to obtain a photoactive layer solution. The solution was stirred and heated to 80° C. overnight in a nitrogen-filled glovebox. The next day, 3.0% by volume of 1,8-diiodooctane (DIO) was added and then spin-coated onto the photoactive layer.

The indium tin oxide formed glass substrate was cleaned by sonication successively in acetone and isopropanol. Each step of 15 minutes was repeated twice and the freshly cleaned substrate was left overnight at 60° C. to dry. As the fabrication progressed, the substrate was cleaned in the UV-ozone chamber for an additional 1.5 minutes and the electron transfer layer was immediately spin-coated on top.

The sol-gel electron transfer layer solution was directly filtered through indium tin oxide with a 0.25 μm poly(vinylidene fluoride) filter and spin-cast at 4000 rpm for 40 seconds. The films were then annealed at 250° C. for 15 minutes and transferred directly to a nitrogen-filled glovebox.

The photoactive layer was applied to the electron transfer layer via spin coating at 600 rpm for 40 seconds with this solution, and the substrate was preheated at 110° C. and a glass substrate for overnight solvent annealing. Transferred to a Petri dish.

After annealing, the substrate was placed on a vacuum evaporator where MoO ₃ (hole transport layer) and Ag (anode) were sequentially deposited by thermal evaporation. Adhesion occurred at pressures <4×10 ⁻⁶ Torr. _MoO3 and Ag had thicknesses of 5.0 nm and 120 nm, respectively. Samples were then encapsulated in glass using an epoxy binder and treated with UV light for 3 minutes.

UV-Visible Absorption Spectroscopy Absorption spectroscopy was performed and measured in the wavelength range from 300 to 1000 nm. A blank glass slide background was subtracted from all spectra. Thin film samples of the polymer were prepared by spin casting a 10 mg/mL solution of the polymer (in 50:50 chlorobenzene:dichlorobenzene) onto a glass slide at 1200 rpm. FIG. 14 represents the UV-visible absorption spectrum of the polymer.

Typical Current Density Typical current density-voltage characteristics are shown in Table 1 below.

Jsc (mA/cm ² ) Short circuit current density (Jsc) is the current density flowing out of a solar cell at zero bias. V _oc (V) The open circuit voltage (V _oc ) is the voltage at which the current in the external circuit is zero. FF (%) Fill factor (FF) is the ratio of maximum power point divided by open circuit voltage and short circuit current. PCE (%) Photovoltaic cell power conversion efficiency (PCE) is the percentage of the solar energy shining on the photovoltaic device that is converted into usable electricity. Rs (Ωcm ² ) Series resistance (Rs) through the photovoltaic cell. Rsh (Ωcm ² ) parallel resistance through the photovoltaic cell.

Finally, it should be noted that the discussion of any reference, especially any reference having a publication date after the priority date of the present application, is not admitted to be prior art to the present invention. At the same time, all of the following claims are incorporated by reference into this detailed description or specification as additional aspects of the present invention.

Although the systems and methods described herein have been described in detail, various changes, substitutions and alterations can be made without departing from the spirit and scope of the invention as defined by the following claims. It should be understood that Those skilled in the art may study suitable embodiments and ascertain other ways of practicing the invention not specifically described herein. While modifications and equivalents of the invention are within the scope of the claims, the inventor intends that the description, abstract and drawings should not be used to limit the scope of the invention. It is expressly intended that the invention be as broad as the following claims and their equivalents.

Claims (8)

Repeating unit A, where repeating unit A is

comprising;
Repeating unit B, where repeating unit B is

or

comprising; and
at least one optional repeating unit D, wherein repeating unit D comprises an aryl group;
A copolymer comprising
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups, and
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups;
the aryl group is 3,3'difluoro-2,2'-bithiophene ,
copolymer. Repeating unit A, where repeating unit A is

comprising;
Repeating unit B, where repeating unit B is

or

comprising; and
at least one optional repeating unit D, wherein repeating unit D comprises an aryl group;
A copolymer comprising
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups, and
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups;
The copolymer comprises repeating unit E:

comprising
copolymer. Repeating unit A, where repeating unit A is

comprising;
Repeating unit B, where repeating unit B is

or

comprising; and
at least one optional repeating unit D, wherein repeating unit D comprises an aryl group;
A copolymer comprising
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups, and
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups;
The copolymer comprises repeating unit F:

comprising
copolymer. Repeating unit A, where repeating unit A is

comprising;
Repeating unit B, where repeating unit B is

or

comprising; and
at least one optional repeating unit D, wherein repeating unit D comprises an aryl group;
A copolymer comprising
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups, and
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups;
The copolymer comprises repeating unit G:

comprising
copolymer. Repeating unit A, where repeating unit A is

comprising;
Repeating unit B, where repeating unit B is

or

comprising; and
at least one optional repeating unit D, wherein repeating unit D comprises an aryl group;
A copolymer comprising
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups, and
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups;
The copolymer comprises repeating unit H:

comprising
copolymer. Repeating unit A, where repeating unit A is

comprising;
Repeating unit B, where repeating unit B is

or

comprising; and
at least one optional repeating unit D, wherein repeating unit D comprises an aryl group;
A copolymer comprising
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups, and
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups;
the copolymer forms a polymer bandgap greater than 1.8 eV;
copolymer. Repeating unit E, where repeating unit E is

comprising;
Repeating unit H, where repeating unit H is

comprising;
Any repeating unit J, where repeating unit J is

and repeat unit K, where repeat unit K is

comprising
A copolymer comprising
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups;
R ₁ , R ₂ , R ₃ , and R ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups, and D is an aryl group. said copolymer comprising: Repeating unit F, where repeating unit F is

comprising;
Repeating unit G, where repeating unit G is

comprising;
Repeating unit J, where repeating unit J is

and repeat unit K, where repeat unit K is

comprising
a copolymer,
X ₁ , X ₂ , X ₃ , and X ₄ are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, ester, ketone, amide and aryl groups;
_R5 and _R6 are independently selected from the group consisting of: H, Cl, F, CN, alkyl, alkoxy, alkylthio, ester, ketone and aryl groups, and D comprises an aryl group.

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