N-TYPE CONJUGATED POLYMERS AND BLENDS, AND METHOD FOR PREPARING THE SAME AND APPLICATION

Abstract

The present invention relates to n-type conjugated polymers and blends, which is made from aromatic diketone with active methylene or an enolic transformation product thereof, and is obtained directly by polymerization reaction in the presence of an oxidant. The reaction described does not require precious metal catalysis and is insensitive to a reaction atmosphere. A process is simple and inexpensive and suitable for commercial applications. Meanwhile, the modulation of the conductivity of the n-type conjugated polymers can be achieved by ionic modification. The n-type conjugated polymers can be applied to an organic optoelectronic device to achieve an excellent photovoltaic effect.

Claims

1. N-type conjugated polymers and blends, comprising n-type conjugated polymers containing a counterion, and/or the n-type conjugated polymers, wherein, the n-type conjugated polymers containing the counterion comprise one or more polymerization units 1, the polymerization unit 1 has the following structure (I): ##STR00062## the n-type conjugated polymers comprise one or more polymerization units 2, the polymerization unit 2 has the following structure (II): ##STR00063## in each of the polymerization unit 1 or the polymerization unit 2, X is independently selected from O, S, Se, Te or N-R.sub.1; the R.sub.1 is selected from one or more of a hydrogen atom, alkyl, alkylidene, an alkyl derivative, and an alkylidene derivative; one or more carbons on the alkyl derivative or the alkylidene derivative are substituted with one or more of an oxygen atom, amino, sulfonyl, carbonyl, aryl, alkenyl, alkynyl, ester, cyano, and nitro; and/or one or more hydrogens on the alkyl derivative or alkylidene derivative are substituted with one or more of halogen, hydroxyl, the amino, carboxyl, the cyano, the nitro, the aryl, alkylene, and alkyne; where m, n and k are positive integers; the M is a conjugated portion of structures of the n-type conjugated polymers containing the counterion or the n-type conjugated polymers, and a structure of the M is selected from one of aromatic ring, aromatic heterocycle, fused aromatic ring, fused aromatic heterocycle; the M is a counterion in the structure of the n-type conjugated polymers containing the counterion or the n-type conjugated polymers, and the counterion is selected from one of an organic cation or an inorganic cation; the n-type conjugated polymers and blends are prepared from a raw material (III), and the raw material (III) has the following structure: ##STR00064## and/or an enol-transformed form of the raw material; the enol-transformed form is ##STR00065## ##STR00066## .

2. The n-type conjugated polymers and blends according to claim 1, wherein a structure of a conjugated portion M of the structures of the n-type conjugated polymers containing the counterion or the n-type conjugated polymers are independently selected from the following structures of: ##STR00067## ##STR00068## ##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074## ##STR00075## ##STR00076## ##STR00077## ##STR00078## ##STR00079## ##STR00080## ##STR00081## ##STR00082## ##STR00083## ##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088## ##STR00089## ##STR00090## wherein the X.sub.2-X.sub.4 are independently selected from O, S, Se, Te or N-R6; R.sub.2-R.sub.6 is independently selected from one or more of the hydrogen atom, the hydroxyl, the nitro, the halogen, the cyano, the nitro, the alkyl, the alkyl derivative, the alkylidene, and the alkylidene derivative; one or more carbons on the alkyl derivative or the alkylidene derivative are substituted with one or more of the oxygen atom, the amino, the sulfonyl, the carbonyl, the aryl, the alkenyl, the alkynyl, the ester, the cyano, and the nitro; and/or one or more hydrogens on the alkyl derivative or the alkylidene derivative are substituted with one or more of the halogen, the hydroxyl, the amino, the carboxyl, the cyano, the nitro, the aryl, the alkylene, and the alkyne.

3. The n-type conjugated polymers and blends according to claim 1, wherein a structure of a counterion Y of the structures of the n-type conjugated polymers containing the counterion is selected from one of the following structures: ##STR00091## ##STR00092## ##STR00093## ##STR00094## ##STR00095## Na.sup.+, K.sup.+, Mg.sup.2+, Ca.sup.2+, Ba.sup.2+, A1.sup.3+, Fe.sup.2+, Fe.sup.3+, Zn.sup.2+, Cu.sup.2+ and Ag.sup.+; or is selected from one of an amine-salt-type cationic surfactant, a quaternary-ammonium-salt-type cationic surfactant, a heterocycl-type cationic surfactant, a rhodonium salt, a sulfonium salt, iodine, and a smart salt compound.

4. The n-type conjugated polymers and blends according to claim 1, wherein (1) when the n-type conjugated polymers containing the counterion are a homopolymer, the structures of the n-type conjugated polymers containing the counterion are selected from one of the following structures: ##STR00096## ##STR00097## ##STR00098## ##STR00099## ##STR00100## or (2) when the n-type conjugated polymers containing the counterion are a copolymer, the structure of each of the polymerization unit 1 of the n-type conjugated polymers containing the counterion is independently selected from the following structures: ##STR00101## ##STR00102## ##STR00103## ##STR00104## ##STR00105## wherein, the R.sub.1 is selected from one or more of a hydrogen atom, alkyl, alkylidene, an alkyl derivative, and an alkylidene derivative; one or more carbons on the alkyl derivative or the alkylidene derivative are substituted with one or more of the oxygen atom, the amino, the sulfonyl, the carbonyl, the aryl, the alkenyl, the alkynyl, the ester, the cyano, and the nitro; and/or one or more hydrogens on the alkyl derivative or alkylidene derivative are substituted with one or more of the halogen, the hydroxyl, the amino, the carboxyl, the cyano, the nitro, the aryl, the alkylene, and the alkyne; where m, n and k are positive integers; the M is the conjugated portion of the structures of the n-type conjugated polymers containing the counterion, and the structure of the M is selected from one of an the aromatic ring, the aromatic heterocycle, the fused aromatic ring, the fused aromatic heterocycle; the Y is the counterion portion of the n-type conjugated polymers containing the counterion, and the counterion is selected from one of an organic cation and an inorganic cation.

5. The n-type conjugated polymers and blends according to claim 1, wherein (1) when the n-type conjugated polymers are the homopolymer, the structures of the n-type conjugated polymers are selected from one of the following structures: ##STR00106## ##STR00107## ##STR00108## ##STR00109## ##STR00110## (2) when the n-type conjugated polymers are the copolymer, a structure of each of the polymerization unit 2 of the n-type conjugated polymers is independently selected from the following structures: ##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115## the n1-n5 are independently positive integers.

6. The n-type conjugated polymers and blends according to claim 1, wherein a dynamic interconversion is provided between the n-type conjugated polymers containing the counterion and the n-type conjugated polymers.

7. The n-type conjugated polymers and blends according to claim 6, wherein a ratio of an amount of substance of the n-type conjugated polymers containing the counterion to an amount of substance of the n-type conjugated polymers is 0.1-10.

8. A method for preparing the n-type conjugated polymers and blends according to claim 1, wherein (1) when the n-type conjugated polymers containing a counterion and/or the n-type conjugated polymers are a homopolymer, the method of preparing the n-type conjugated polymers and blends comprise the following steps of: mixing a raw material (III) and an oxidant and/or an ion exchange adjuvant in a solvent and heating to obtain the homopolymer; or (2) when the n-type conjugated polymers containing the counterion and/or the n-type conjugated polymers are a copolymer, the method of preparing the n-type conjugated polymers and blends comprise the following steps of: mixing two or more of the raw materials (III), and the oxidant and/or the ion exchange adjuvant in the solvent and heating to obtain the copolymer.

9. The method for preparing the n-type conjugated polymers and blends according to claim 8, wherein the oxidant is selected from one or more of an organic type oxidant and an inorganic type oxidant.

10. The method for preparing the n-type conjugated polymers and blends according to claim 8, wherein the oxidant is selected from one or more of oxygen, peroxide, metal halide, persulfate, perborate, subhaloate, halogenite, a quinones compound, and a benzylhydroperoxide compound.

11. The method for preparing the n-type conjugated polymers and blends according to claim 8, wherein the ion exchange adjuvant is selected from one or more of an inorganic salt containing a cation, and an organic salt containing a cation.

12. The method for preparing the n-type conjugated polymers and blends according to claim 8, wherein the solvent is selected from a solvent 1 or a solvent 2, or a mixture of the solvent 1 and the solvent 2; the solvent 1 is selected from one or more of water, a nitrile solvent, an aromatic solvent, an alicyclic hydrocarbon solvent, an alicyclic hydrocarbon solvent, a halogenated hydrocarbon solvent, an alcohol solvent, an ether solvent, an ester solvent, a sulfone solvent, a ketone solvent, and an amide solvent; the solvent 2 is a deuterated solvent of the solvent 1.

13. Application of the n-type conjugated polymers and blends according to claim 1 in an organic optoelectronic device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0077] FIG. 1 shows an absorption spectrogram of a product in Embodiment 1 in a thin film state.

[0078] FIG. 2 shows a graph of a gel permeation chromatography test of a product in Embodiment 1.

[0079] FIG. 3 shows an X-ray photoelectron energy spectrum of a product in Embodiment 1, where Chart (A) shows an XPS spectrum of an element of oxygen (oxygen 1s peak) and Chart (B) shows a total spectrum.

[0080] FIG. 4 shows a schematic diagram of a four-probe conductivity test of a product in Test Example 1.

[0081] FIG. 5 shows a graph of voltage versus current data for a four-probe conductivity test of a product in Embodiment 1 of Test Example 1, where Chart (A) shows a graph of current measurements in a four-probe, and Chart (B) shows a graph of voltage measurements in a four-probe.

[0082] FIG. 6 shows a graph of a Seebeck coefficient test for a product in Embodiment 1.

[0083] FIG. 7 shows a schematic diagram of an organic electrochemical transistor device.

[0084] FIG. 8 shows a trans-conductivity test diagram of a product in Embodiment 1 in an organic electrochemical transistor device.

DETAILED DESCRIPTION OF EMBODIMENTS

[0085] In order to illustrate the technical solutions of the present invention more clearly, the following embodiments are given. Unless otherwise stated, raw materials, reactions and post-processing means in the embodiments are common raw materials on market and technical means well known to a person skilled in the art.

[0086] As one of the raw materials in this embodiment of the invention, 3,7-dihydrobenzo[1,2-b:4,5-b′] difuran-2,6-dione, was prepared according to the literature (A BDOPV-Based Donor-Acceptor Polymer for High-Performance n-Type and Oxygen-Doped Ambipolar Field-Effect Transistors. Adv. Mater. 2013, 25(45), 6589).

[0087] An oxidant in the embodiment was duroquinone, coenzyme Q10 or ferric trichloride, which was purchased from Shanghai Bide Pharmaceutical Technology Co. Ltd.

[0088] Embodiment 1: a method for preparing n-type conjugated polymers and blends

##STR00060##

3,7-dihydrobenzo [1,2-b:4,5-b′] difuran-2,6-dione (1 mmol), and an oxidant of duroquinone (1.5 mmol), were dissolved in 2 ml of dimethyl sulfoxide (DMSO), degassed under vacuum, and protected by filling with nitrogen. The above mixture solution was stirred in a nitrogen atmosphere at a temperature of 100° C. for 4 h. A resulting crude product was then diluted to approximately 10 mg/ml with DMSO and filtered using a polytetrafluoroethylene filter head with 0.45 .Math.m of a pore size. A resulting filtrate was concentrated using a rotary evaporator and dialyzed in a DMSO solution for 7 days using a dialysis bag (a cut-off molecular weight = 10 kDa) to obtain the product of the n-type conjugated polymers and blends. Where Formula I and Formula II could be interconverted by resonance as described above, and m/(n1+n2) was about0.86. The test method for a ratio was obtained by fitting using an X-ray photoelectron energy spectrum (the same applies hereinafter). A test was performed by gel permeation chromatography with DMSO as a mobile phase. The molecular weight Mn=428.2 kDa and PDI=1.22.

[0089] FIG. 1 showed an absorption spectrogram of a product in Embodiment 1 in a thin film state with an absorption edge over 2400 nm, illustrating the presence of polarons in the polymer and proving the presence of negative charges in a mixture system that could move freely in a conjugated backbone. FIG. 2 showed a graph of a gel permeation chromatography test of a product in Embodiment 1, illustrating the production of the polymer and a supramolecular compound.

[0090] FIG. 3 showed the X-ray photoelectron energy spectrum of a product in Embodiment 1. Chart (A) showed an XPS spectrum of an element of oxygen (oxygen 1s peak) and Chart (B) showed a total spectrum. Therefore, a semi-quantitative ratio between different peaks of an element of oxygen in FIG. 3 could be used to calculate the relationship between m as well as n1 and n2. Therefore, with this method, the relative contents of Formula I and Formula II can be determined.

[0091] Embodiment 2: a method for preparing n-type conjugated polymers and blends

##STR00061##

3,7-dihydrobenzo [1,2-b:4,5-b′] difuran-2,6-dione (1 mmol), and an oxidant of ferric trichloride (2 mmol) were dissolved in 2 ml of N, N-dimethylformamide (DMF), degassed under vacuum, and protected by filling with nitrogen. The above mixturesolution was stirred in a nitrogen atmosphere at a temperature of 100° C. for 2 h. The resulting product of the n-type conjugated polymers and blends were gradually precipitated out from a reaction system, cooled to a room temperature and then added with 50 mL of ethanol. After thorough stirring, the product was filtered and washed with deionized water, ethanol and tetrahydrofuran. The resulting product of the n-type conjugated polymers and blends was a mixture of Formula (I), Formula (II), Formula (III) and Formula (IV). The resulting product was insoluble in an organic solvent due to coupling of a ferric ion. A solid was characterized.

[0092] Where, 2(k1+k3)+3(k2+k5)+(k4+k6)=m1+m2+m3+m4+m5+m6.

[0093] and (k4+k6):(k1+k3):(k2+k5) was approximately 8:1:0.2.

[0094] (m1+m2+m3+m4+m5+m6):(n1+n2+n3+n4+n5+n6+n7) was about 0.9.

[0095] Embodiment 3: a method for preparing n-type conjugated polymers and blends (1) Benzodithiophene (23 mmol) was dissolved in anhydrous tetrahydrofuran (300 ml), then cooled down to a temperature of -78° C., slowly added into n-butyllithium (2.5 M of a hexane solution, 25.8 ml, 64.4 mmol) within 90 min, stirred for 3 h at a temperature of -78° C., then warmed up to 0° C., added with tri-n-butyl borate (60 mmol), stirred for 1 h, then gradually warmed up to the room temperature of 25° C. and continuously stirred for 8 h. A solution was concentrated to 200 ml using a rotary evaporator, added with 200 ml of 0.5 M of hydrochloric acid and filtered to obtain a crude product. A product was precipitated out from the crude product using tetrahydrofuran/hexane, washed with ice-toluene and dried to obtain a solid (yield = 61%) for a next step of reaction.

[0096] The solid (7.5 mmol) from the previous step was dissolved in tetrahydrofuran (100 ml), added with 2.5 ml of an aqueous hydrogen peroxide solution (30 wt%) at a temperature of 0° C., and stirred for 6 h at a room temperature. After the solvent was removed using the rotary evaporator, the product was purified using a silica gel packed chromatographic column (200-300 mesh) with ethyl acetate: petroleum ether = 4:1 as an eluent. An obtained solid was washed with hexane and methanol to obtain 3,7-dihydrobenzo[1,2-b:4,5-b′] dithiophene-2,6-dione (yield = 53%). .sup.1HNMR(CDCl.sub.3, 500 MHz) δppm : 7.31 (s, 2H), 3.98 (s, 4H).

[0097] 3,7-dihydrobenzo [1,2-b:4,5-b′] dithiophene-2,6-dione (1 mmol), and duroquinone (2 mmol) were dissolved in 2 ml of DMSO, degassed under vacuum and protected by filling with nitrogen. The solution was stirred for 10 h under the nitrogen atmosphere at a temperature of 120° C., diluted to about 10 mg/ml and filtered using a 0.45 .Math.m pore size of a polytetrafluoroethylene filter head. The solution was concentrated using the rotary evaporator and dialyzed in the DMSO solution using a dialysis bag (a cut-off molecular weight = 10 kDa) for 3 days to obtain the product of the n-type conjugated polymers and blends. The resulting product of the n-type conjugated polymers and blends was a mixture of Formula (I) and Formula (II). Formula I and Formula II could be interconverted by resonance as described above, and m/(n1+n2) was about 0.42. A test was performed by gel permeation chromatography with DMSO as a mobile phase. The molecular weight Mn=12 kDa and PDI=1.31.

[0098] Embodiment 4: a method for preparing n-type conjugated polymers and blends 20 mL of a DMSO solution of the product obtained in Embodiment 1 (a concentration of 15 mg/mL) was diluted with 20 mL of DMSO, added with 2 g of tetrabutylammonium bromide, and stirred at a room temperature for 14 days. A part of an ion exchange product was gradually precipitated out during a reaction. 50 mL of ethanol was added to a reaction system, which was stirred thoroughly and filtered. A resulting powder was washed with the ethanol and tetrahydrofuran.

[0099] Where k1+k2+k3+k4=m1+m2+m3+m4=m,

[0100] n3+n4+n5+n6+n7+n8+n9=n1+n2.

[0101] (k2+k4)/(k1+k3) was about 0.2.

[0102] Embodiment 5: a method for preparing n-type conjugated polymers and blends

[0103] A DMSO solution of 40 .Math.L of a product obtained in Embodiment 1 (concentration of 15 mg/mL) was added dropwise onto a 10 mm × 10 mm glass substrate, and dried to obtain a film. The film was immersed in an aqueous solution of saturated NaCl for 12 h, then washed with deionized water and dried to obtain a film of ion exchange product of the n-type conjugated polymers and blends, which was directly performed with subsequent characterization.

[0104] Where k1+k2+k3+k4=m1+m2+m3+m4=m,

[0105] n3+n4+n5+n6+n7+n8+n9=n1+n2.

[0106] (k2+k4)/(k1+k3) was about 0.04.

[0107] Embodiment 6: a method for preparing n-type conjugated polymers and blends

[0108] Under the protection of nitrogen, 3,7-dihydrobenzo [1,2-b:4,5-b′] difuran-2,6-dione (1 mmol) was dissolved in 5 mL of trichloromethane, added with 2 mmol of triethylamine, and stirred at a room temperature. After the solution turned dark green, an oxidant of duroquinone (1.5 mmol) was added. The above mixture solution was stirred in a nitrogen atmosphere at a temperature of 100° C. for 24 h and filtered to obtain a crude product. A resulting crude product was then washed with tetrahydrofuran, dissolved in 20 mL of DMSO, and filtered using a 0.45 .Math.m pore size of a polytetrafluoroethylene filter head. A resulting filtrate was dialyzed in a DMSO solution using a dialysis bag (a cut-off molecular weight = 10 kDa) for 7 days to obtain the product of the n-type conjugated polymers and blends. Formula I and Formula II could be interconverted by resonance as described above, and m/(n1+n2) was about 0.62. A test was performed by gel permeation chromatography with DMSO as a mobile phase. The molecular weight Mn= 11 kDa and PDI=1.72.

Test Example 1

[0109] With a DMSO solution of n-type conjugated polymers and blends obtained in Embodiment 1, a film was prepared on a glass substrate using a spin-coating film formation method. After the film was dried under vacuum, the conductivity of the film was measured using a four-foot probe method. FIG. 4 showed a schematic diagram of a four-probe conductivity test of a product of Embodiment 1. The specific steps were as follows:

[0110] A quartz glass sheet was washed with acetone, a micron-level semiconductor special detergent, deionized water and isopropyl alcohol as a cleaning solvent in ultrasonic cleaner in turn. The surface of the quartz glass sheet was dried with nitrogen gas after washing, and was dried with an infrared lamp. The quartz glass sheet was then placed in a constant temperature oven for backup. Before use, the glass sheet was bombarded with plasma in a plasma etcher for 10 min.

[0111] After the preparation of the glass sheet was finished, the glass sheet was placed on a heating table, heated at a temperature of 110° C. and transferred to a rotary gelatinometer (KW-4A). The product of Embodiment 1 prepared above was spin-coated at a high speed (the mass concentration of the conjugated polymers solution was 15 mg/ml), and the thickness of a monitored film was simultaneously measured realistically with a step meter. After film formation was completed, voltage and current curves were tested using a four-foot probe conductivity tester. A test schematic diagram was shown in FIG. 4. A voltage V and a current I were shown in FIG. 5. The conductivity σ was calculated using a film thickness d and a correction factor, with a calculated formula as:

[0112] σ = I/(C x V x d) (where C was determined by both built-in probe calibration parameters of an instrument and a specimen size).

[0113] Powder of products obtained in Embodiment 2 and Embodiment 4 was prepared as a thin film with a diameter of 15 mm and a thickness of 1 mm using a press method. The conductivity of the film was measured using the four-foot probe method.

[0114] The conductivity of the film of the product obtained after ion exchange in Embodiment 5 was directly measured using a four-foot probe method with the following results.

TABLE-US-00001 Conductivity Tests of Products of Embodiment 1, Embodiment 2, Embodiment 4 and Embodiment 5 N-type Conjugated Polymers and Blends Conductivity (S/cm) Embodiment 1 2150 Embodiment 2 942 Embodiment 4 1720 Embodiment 5 2408

[0115] As can be seen from Table 1, the n-type conjugated polymers and blends prepared by the present invention had high conductivity. The regulation of the conductivity could be achieved by different counterions.

[0116] Here, the n-type conjugated polymers and blends of Embodiment 1 were illustrated as follows: the n-type conjugated polymers and blends prepared by the present invention could resonate hydrogen protons and negative charges on a backbone. In addition, in a solid state, due to the formation of a supramolecular interaction, the hydrogen protons were bound between molecules, thus weakening binding to the negative charges, allowing the negative charges to move freely on a conjugated backbone and achieving high n-type conductivity.

Test Example 2

[0117] A thermoelectric test was performed on n-type conjugated polymers and blends obtained in an embodiment.

[0118] The thermoelectric properties of a material were commonly described by the thermoelectric figure of merit (ZT), which was given by the following formula:

[00001]$ZT=S2\sigma T/\kappa ;$

[0119] Where S represents a Seebeck coefficient. σ represents conductivity. κ represents thermal conductivity, and T represents a temperature at which a device operates. The thermal conductivity of an organic material was much lower than that of an inorganic material, so a power factor (PF) was commonly used to describe the thermoelectric properties of the organic material, where PF=S2σ.

[0120] In this test example, taking as an example the n-type conjugated polymers and blends prepared above, a sample preparation process was the same as the one used in Test Example 1 to test the Seebeck coefficient and characterize thermoelectric properties.

[0121] The two ends of a device were placed in a temperature gradient field. FIG. 6 showed a diagram of a trend of the thermal voltage difference of a product in Embodiment 1, and a fitted diagram of a trend of the thermal voltage difference of a product in Embodiment 1 with temperature. A corresponding temperature difference electric potential was tested with the change in temperature difference between the two ends of the device to measure the Seebeck coefficient. As seen on FIG. 6, the polymers of the embodiment of the present invention exhibited the Seebeck effect of the product at a weak temperature difference and generated the temperature difference electric potential of more than 30 .Math.V/K.

[0122] FIG. 6 showed the conductivity-Seebeck coefficient-power factor performance graph for the product of Embodiment 1. The power factor was obtained from PF=S2σ. From the above tests, it can be obtained that the power factor was close to 100 .Math.Wm.sup.-1K.sup.-2 at a room temperature, and was at a higher level among the n-type conjugated polymers in the prior art.

[0123] Relevant data were shown in Table 2.

TABLE-US-00002 Seebeck Coefficients of n-type Conjugated Polymers and Blends of Embodiment 1, Embodiment 2 and Embodiment 4 N-type Conjugated Polymers and Blends Seebeck Coefficient (.Math.V/K) Power Factor (.Math.Wm.sup.-1K.sup.-2) Embodiment 1 -19.09 92.9 Embodiment 2 -28.67 77.4 Embodiment 4 -23.59 95.7

Test Example 3

[0124] The n-type conjugated polymers and blends obtained in Embodiment 1 were tested for an organic electrochemical transistor device. The organic electrochemical transistor device was shown in FIG. 7.

[0125] The manufacturing process of the above organic electrochemical transistor was as follows: First, a glass base was washed with acetone and isopropyl alcohol in turn, and then the surface of the glass base was blown with nitrogen gas to be dried. A layer of Cr/Au (10 nm/100 nm) substrate was deposited on a glass substrate using a sputtering method to build a source electrode and a drain electrode. The surface of the substrate was passivated and spin-coated with a DMSO solution of the n-type conjugated polymers in Embodiment 1 as an active layer material in the organic electrochemical transistor, and baked at a temperature of 100° C. for 10 min under nitrogen, with a film thickness of about 70 nm and a trench area of 1 mm x 1 mm. The performance of the organic electrochemical transistor was characterized in air using an Ag/AgCl electrode as a gate electrode, a 0.1 M NaCl solution as an electrolyte, and Keithley 4200 to record a voltage Vgs between the source electrode and the gate electrode and a current Ids between the drain electrode and the gate electrode.

[0126] The tested performance of the above organic electrochemical transistor device was shown in FIG. 8. The organic electrochemical transistor device based on the n-type conjugated polymers and blends had a good electrochemical response with a transconductivity close to 11 mS, and had important application prospects in the field of organic biosensing.

[0127] The above test examples illustrated that the n-type conjugated polymers and blends of the present invention had a wide range of promising applications as a highly conductive material in an organic optoelectronic device.

[0128] It is obvious to a person skilled in the art that the present invention not limited to the details of the exemplary embodiments described above, and that the present invention can be realized in other specific forms without departing from the spirit or basic features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting from any standpoint. The scope of the present invention is defined by the appended claims rather than the above description. It is therefore intended that all variations falling within the meaning and scope of equivalent elements of claims be encompassed by the present invention.

[0129] In addition, it should be understood that although this specification is described in terms of embodiments, not each embodiment only includes an independent technical solution. This description in the specification is only for the sake of clarity. A person skilled in the art should take the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementations that can be understood by a person skilled in the art.