Patent Application
20240301132
The present invention belongs to an n-type organic semiconductor materials technical field, and specifically, relates to an n-type conjugated polymer, a preparation method and a use thereof.
A structure of a conjugated polymer contains a conjugated system composed of delocalized π-electrons. Therefore, the conjugated polymer exhibits special optical and electrical properties, and has drawn widespread attention from scientists. Photoelectric materials and semiconductor materials applied to devices have not only electronic properties of metals or semiconductors, but also the characteristics of low costs, light weight, low-temperature processing, and easy large-area preparation. They meet the requirements of large-scale industrial production and large-area promotion, and have broad commercial prospects. Currently, the conjugated polymer has achieved a series of impressive results in the fields of organic photovoltaic (OPV) cells, organic light emitting diodes (OLED), organic field effect transistors (OFET), and organic thermoelectrics (OTE).
A high-performance organic electron device usually needs p-type and n-type semiconductor materials at the same time during operation. PEDOT:PSS, as one of the p-type materials currently commercially applied, has achieved great success in semiconductors due to its characteristics of high conductivity and printability.
However, compared with the mature p-type material, an n-type organic material, especially an organic n-type conjugated polymer with high conductivity, lacks a corresponding synthesis strategy. Due to the limitation of factors, such as low electron mobility, poor air stability, and a need for a long insulating alkyl chain for allowing solution processing, of the n-type organic semiconductor material, development of an n-type organic semiconductor material that has high conductivity, simple synthesis process, and low costs and that is applicable to solution processing is a hotspot in the current research.
A 3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione molecule contains two strong electron-withdrawing functional groups, which can effectively reduce the lowest unoccupied molecular orbital (LUMO) of a polymer. Therefore, the electron mobility of the polymer is improved, and the stability of n-type doping of the polymer is ensured. There are many reports on polymers based on 3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione. For example, a document (Toward High Performance n-Type Thermoelectric Materials by Rational Modification of BDPPV Backbones. J. Am. Chem. Soc. 2015, 137, 6979) reports a benzodifurandione-based on polymer BDPPV whose highest conductivity of 14 S/cm can be achieve by optimizing a dopant. A document (High Conductivity and Electron-Transfer Validation in an n-Type Fluoride-Anion-Doped Polymer for Thermoelectrics in Air. Adv. Mater. 2017, 29, 1606928) reports an n-type thermoelectric material that has good air stability and is obtained by doping a benzodifurandione-based polymer with tetrabutylammonium fluoride. In addition, a document (Rigid Coplanar Polymers for Stable n-Type Polymer Thermoelectrics. Angew. Chem. Int. Ed. 2019, 58, 11390) reports a benzodifurandione-based polymer LPPV that has air stability and high conductivity and is obtained through acid-catalyzed aldol condensation reaction polymerization without using a noble metal catalyst.
However, due to the excellent planarity of 3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione, a long alkyl chain needs to be introduced on a polymerization unit of current most polymers based on this unit to ensure the solubility of the polymers in organic solvents. Moreover, an additional dopant (such as N-DMBI) is used for doping to achieve high conductivity. The polymers cannot keep stable under air atmosphere for a long term.
For diketone fused ring compounds, a document (Synthese, Charakterisierung und Halbleitereigenschaften eines polymeren Indopheninhomologen. Macro. Chem. Phys. 1975, 176, 333) discloses a p-type quinoid polymer with conductivity that can be formed through dehydration polymerization under the condition of sulfuric acid catalysis. The patent application WO 2014/071524 discloses a polymer containing a fused ring structure, and introduces its application as an organic semiconductor in OFET. The patent application US 2019/0048015 A1 discloses a class of near-infrared organic semiconductor polymers without noble metal catalysis.
In addition, the patent application CN108699073 discloses a semiconductor polymer and a synthesis method thereof. A structure of the semiconductor polymer is
However, during preparation of the polymer, tetraketone A
is employed as a raw material, which is an intermediate after oxidation reaction. Synthesis of this intermediate needs additional processing costs, so the synthesis route is uneconomical, and synthesis is difficult to commercialize. Moreover, actually for some tetraketone A structures such as
a preparation method is not disclosed in the prior art, so a polymer preparation method suitable for commercialization is difficult to obtain from the disclosed documents.
The foregoing disclosed polymers do not involve any n-type conductive properties, or the relevant data are not ideal. All the disclosed polymer structures contain an alkyl side chain, and there is no report on a polymer structure that allows solution processing in the absence of an alkyl chain and a preparation method.
Based on the above, development of a class of n-type highly conductive conjugated polymers that have simple structures, simple synthesis process, and low costs, are applicable to solution processing, are directly synthesized by a preparation method suitable for commercialization, and are applied in the organic photoelectric field to achieve an ideal photoelectric effect is a problem to be solved urgently.
In order to overcome the shortcomings and deficiencies in the prior art, an objective of the present invention is to provide an n-type conjugated polymer and a preparation method thereof. In the method of the present invention, an aromatic diketone substance having active methylene is employed as a raw material, and an n-type conjugated polymer is directly prepared through a polymerization reaction in the presence of an oxidant. The reaction does not require noble metal catalysis and is not sensitive to the reaction atmosphere, the process is simple, and the cost is low, so the preparation method is suitable for commercial application. The n-type conjugated polymer prepared by the method of the present invention has good solubility in a general organic solvent, thus allowing solution processing. Moreover, when applied in an organic photoelectric device, the n-type conjugated polymer can achieve an excellent photoelectric effect.
Another objective of the present invention is to provide a use of the n-type conjugated polymer prepared by the foregoing method. The n-type conjugated polymer is applied in an organic photoelectric device. Specifically, the n-type conjugated polymer of the present invention is applied in an organic photovoltaic cell as an electron transport layer, or as a thermoelectric material, or as an electromagnetic shielding material.
Objectives of the present invention are realized by the following technical solutions.
An n-type conjugated polymer is a homopolymer or copolymer. The n-type conjugated polymer includes one or more polymerization units. The polymerization unit is a structure represented by formula I and/or a structure represented by formula II, and/or a corresponding enol-type transformation form thereof:
Further, a structure of the n-type conjugated polymer is specifically formula I, formula II, a structure composed of formula I and formula II, a structure composed of formula I and formula I, a structure composed of formula II and formula II, an enol-type transformation form corresponding to formula I, an enol-type transformation form corresponding to formula II, a structure composed of formula I and the corresponding enol-type transformation form thereof, a structure composed of formula II and the corresponding enol-type transformation form thereof, or a structure composed of formula I, formula II, and the corresponding enol-type transformation forms. In the structure composed of formula I and formula I, formula I is different from formula I. In the structure composed of formula II and formula II, formula II is different from formula II. The structure composed of formula I and formula II contains one or more formulae I, and contains one or more formulae II, formulae I are the same or different, and formulae II are the same or different.
In formula I, X is independently selected from O, S, Se, Te or N—R1;
The heteroaromatic ring refers to a ring structure that has a conjugated planar ring system and in which a bond between atoms is covered by a delocalized π-electron cloud and atoms forming the ring further contain at least one heteroatom (such N, O or S) in addition to a carbon atom. For example, the heteroaromatic ring is thiophene, furan or pyrrole.
The fused aromatic ring refers to a structure formed by fusing (that is, sharing a ring edge) two or more aromatic rings that have a conjugated planar ring system and in which a bond between atoms is covered by a delocalized π-electron cloud. For example, the fused aromatic ring is naphthalene, anthracene, or a derivative thereof.
The fused heteroaromatic ring refers to a structure formed by fusing two or more aromatic rings that have a conjugated planar ring system and in which a bond between atoms is covered by a delocalized π-electron cloud, and furthermore, constituent atoms in at least one ring further contain at least one heteroatom (such N, O or S) in addition to a carbon atom. For example, the fused heteroaromatic ring is quinoline, indole, or a derivative thereof.
In the present invention, the n-type highly conductive conjugated polymer has a plurality of resonance forms. In a case that M is a benzene ring structure, the n-type highly conductive conjugated polymer includes, but is not limited to, the following resonance forms:
and
Further, the different resonance forms may form the following supramolecules through self-assembly under the intermolecular interaction:
It should be noted that in a case that X is an oxygen atom, and M is a benzene ring structure, the prepared compound further has the following tautomers:
and the break line indicates a chain segment of the conjugated polymer.
For the purpose of convenience, the present invention is described with reference to the first resonance form.
Further, the structure of M is selected from the following structures:
It should be noted that in the foregoing optional objects of the structure of M, a dotted line (- - -) in the aromatic ring indicates mutual fusion of the aromatic ring and an adjacent five-membered ring or four-membered ring at this place, namely, a shared ring edge. For example, in a case that the structure of M is represented as
an actual structure of the n-type conjugated polymer is:
or a corresponding enol-type transformation form thereof.
Further, the n-type conjugated polymer is a homopolymer or copolymer.
In a case that the n-type conjugated polymer is a homopolymer, the structure of the n-type conjugated polymer is selected from one of the following structures or corresponding enol-type transformation forms thereof:
In a case that the n-type conjugated polymer is a copolymer, the n-type conjugated polymer includes at least two kinds of polymerization units;
A preparation method for an n-type conjugated polymer includes the following steps:
The reaction monomer is
and/or a corresponding enol-type transformation form thereof.
The corresponding enol-type transformation form is selected from one or more of the following structures:
M and X in the structures have the same definitions as those in the foregoing n-type conjugated polymer.
In a case that the n-type conjugated polymer is a homopolymer, the reaction monomers are compounds with the same structure.
In a case that the n-type conjugated polymer is a copolymer, the reaction monomers are compounds with different structures. That is, the reaction monomers are more than two kinds of compounds represented by formula I′ or more than two kinds of compounds represented by formula II′, or corresponding enol-type transformation forms thereof, or the reaction monomers are a compound represented by formula I′ and a compound represented by formula II′, and/or corresponding enol-type transformation forms thereof.
In a case that the n-type conjugated polymer is a copolymer, the preparation method for the n-type conjugated polymer can also comprise the following steps:
The different polymerization units are preferably more than two of the following structures, and/or corresponding enol-type transformation forms thereof:
In a case that the n-type conjugated polymer is a copolymer, the copolymer may be a bipolymer or multipolymer. Different polymerization units may be polymerized with each other to form a new long-chain copolymer. A structure of the copolymer may be, but is not limited to, the following structures:
The substance having oxidability is selected from a mixture of one or more of organic substances having oxidability and inorganic substance having oxidability.
Further, the substance having oxidability is more than one of oxygen, a peroxide, a metal halide, a persulfate, a perborate, a hypohalite, a chlorite, a bromite, a quinone compound, and a perbenzoate compound.
Specifically, the foregoing substance having oxidability may be, but is not limited to, more than one of oxygen, hydrogen peroxide, sodium peroxide, potassium peroxide, calcium peroxide, zinc peroxide, copper peroxide, iron nitrate, zinc nitrate, nickel nitrate, aluminium nitrate, magnesium nitrate, ammonium nitrate, iron fluoride, iron chloride, iron bromide, iron iodide, sodium perchlorate, potassium perchlorate, sodium perbromate, potassium perbromate, sodium periodate, potassium periodate, potassium perchlorate, sodium perchlorate, potassium perbromate, sodium perbromate, magnesium perchlorate, sodium persulfate, potassium persulfate, magnesium persulfate, zinc persulfate, iron persulfate, copper persulfate, calcium persulfate, potassium perborate, zinc perborate, magnesium perborate, calcium perborate, sodium hypofluorite, potassium hypofluorite, sodium hypochlorite, potassium hypochlorite, iron hypochlorite, copper hypochlorite, sodium hypobromite, potassium hypobromite, sodium hypoiodite, potassium hypoiodite, sodium chlorite, potassium chlorite, iron chlorite, sodium bromite, potassium bromite, sodium iodate, potassium iodate, benzoquinone and a derivative thereof, naphthoquinone and a derivative thereof, anthraquinone and a derivative thereof, phenanthrenequinone and a derivative thereof, and perbenzoic acid and a derivative thereof.
The solvent is selected from a solvent 1, a solvent 2, or a mixture of the solvent 1 and the solvent 2;
Specifically, the foregoing solvent 1 is preferably a polar solvent, and may be, but is not limited to, more than one of tetrahydrofuran, methyltetrahydrofuran, dichloromethane, chloroform, ethyl acetate, propyl acetate, butyl acetate, ethyl propionate, propyl propionate, butyl propionate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, toluene, xylene, trimethylbenzene, chlorobenzene, dichlorobenzene, trichlorobenzene, methanol, ethanol, propanol, ethylene glycol, isobutanol, propylene glycol, acetonitrile, formic acid, acetic acid, propionic acid, trifluoroacetic acid, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dimethylacetamide, acetone, butanone, cyclohexanone, methyl butanone, methyl ether, diethyl ether, propyl ether, pyridine, phenol, N-methylpyrrolidone, ethylene glycol monomethyl ether, triethylene glycol monomethyl ether, triethylamine, tetramethylethylenediamine, trioctylamine, aniline, and hexamethylphosphoramide.
Specifically, the foregoing solvent 2 is a deuterated solvent corresponding to the foregoing solvent 1. For example, the solvent 2 may be, but is not limited to, deuterated chloroform, deuterated chlorobenzene, deuterated ethanol, and the like.
Preferably, the solvent is selected from the solvent 1.
The foregoing n-type conjugated polymer is applied in an organic photoelectric device. The n-type conjugated polymer is applied in an electron transport layer. The electron transport layer includes the foregoing n-type conjugated polymer.
The n-type conjugated polymer is applied in a thermoelectric material. The thermoelectric material includes the foregoing n-type conjugated polymer.
The n-type conjugated polymer is applied in an electromagnetic shielding material. The electromagnetic shielding material includes the foregoing n-type conjugated polymer.
Relative to the prior art, the present invention has the following advantages and beneficial effects.
In order to describe the technical solutions of the present invention more clearly, the following examples are listed. Unless otherwise stated, raw materials, reactions, and post-processing methods in the examples are common raw materials on the market and technical means well-known to those skilled in the art.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione, serving as a raw material in the examples of the present invention, is prepared with reference to the document (A BDOPV-Based Donor-Acceptor Polymer for High-Performance n-Type and Oxygen-Doped Ambipolar Field-Effect Transistors. Adv. Mater. 2013, 25 (45), 6589). A substance having oxidability in the examples is duroquinone or coenzyme Q10 and is purchased from Shanghai Bidepharmatech Co., Ltd.
In the present invention, usage amounts of the aromatic diketone substance serving as a raw material and the substance having oxidability may be in any ratio. For example, the molar ratio is 1:1, 0.01:1, or 1:0.01. The usage amounts of the aromatic diketone and the substance having oxidability are not 0.
When the aromatic diketone substance serving as a raw material reacts under the action of the substance having oxidability, there is no special requirement for the reaction temperature, as long as the aromatic diketone substance can react. For example, the reaction temperature is from room temperature to 150° C.
After stopping the reaction, post-processing is performed. The post-processing is performed by a conventional post-processing method, such as filtering and dialyzing, or filtering, washing, and drying, or precipitating in a precipitant.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (1 mmol) and duroquinone (1 mmol) were dissolved in 2 mL of DMF, and after vacuum degassing, nitrogen was filled for protection. Under the nitrogen atmosphere, an obtained solution was stirred for reaction at 100° C. for 4 h. Then, a prepared crude product was diluted with DMF to about 10 mg/mL, and filtered by using a polytetrafluoroethylene filter head with a pore size of 0.45 μm. An obtained filtrate was concentrated by using a rotary evaporator, and dialysed in a DMF solution by using a dialysis bag (molecular weight cut-off=10 kDa) for 3 days to prepare a product NCPO. The prepared NCPO was tested by gel permeation chromatography with the mobile phase of DMF, the results of test showed that the molecular weight Mn was 14 kDa and PDI was 4.02.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (1 mmol) and duroquinone (1 mmol) were dissolved in 2 mL of DMSO, and after vacuum degassing, nitrogen was filled for protection. Under the nitrogen atmosphere, an obtained solution was stirred for reaction at 100° C. for 1 h. Then, a prepared crude product was diluted with DMSO to about 10 mg/mL, and filtered by using a polytetrafluoroethylene filter head with a pore size of 0.45 μm. An obtained filtrate was concentrated by using a rotary evaporator, and dialysed in a DMSO solution by using a dialysis bag (molecular weight cut-off=15 kDa) for 3 days to prepare a product NCPO. The prepared NCPO was tested by gel permeation chromatography with the mobile phase of DMSO, and the results of the test showed that the molecular weight Mn was 220 kDa and PDI was 2.02.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (1 mmol) and coenzyme Q10 (1 mmol) were dissolved in 2 mL of DMF, and after vacuum degassing, nitrogen was filled for protection. Under the nitrogen atmosphere, an obtained solution was stirred for reaction at 100° C. for 4 h. Then, a prepared crude product was diluted with DMF to about 10 mg/mL, and filtered by using a polytetrafluoroethylene filter head with a pore size of 0.45 μm. An obtained filtrate was concentrated by using a rotary evaporator, and dialysed in a DMF solution by using a dialysis bag (molecular weight cut-off=10 kDa) for 3 days to prepare a product NCPO. The prepared NCPO was tested by gel permeation chromatography with the mobile phase of DMF, and the results of test showed that the molecular weight Mn was 21 kDa and PDI was 1.98.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (1 mmol) and coenzyme Q10 (10 mmol) were dissolved in 4 mL of DMF, and after vacuum degassing, nitrogen was filled for protection. Under the nitrogen atmosphere, an obtained solution was stirred for reaction at 100° C. for 2 h. Then, a prepared crude product was diluted with DMF to about 15 mg/mL, and filtered by using a polytetrafluoroethylene filter head with a pore size of 0.45 μm. An obtained filtrate was concentrated by using a rotary evaporator, and dialysed in a DMF solution by using a dialysis bag (molecular weight cut-off=10 kDa) for 7 days to prepare a product NCPO. The prepared NCPO was tested by gel permeation chromatography with the mobile phase of DMF, and the results of test showed that the molecular weight Mn was 76 kDa and PDI was 1.72.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (1 mmol) and duroquinone (0.1 mmol) serving as an oxidant were dissolved in 2 mL of DMSO. An obtained solution was stirred for reaction at 100° C. for 24 h. Then, a prepared crude product was diluted with DMSO to about 10 mg/mL, and filtered by using a polytetrafluoroethylene filter head with a pore size of 0.45 μm. An obtained filtrate was concentrated by using a rotary evaporator, and dialysed in a DMSO solution by using a dialysis bag (molecular weight cut-off=15 kDa) for 3 days to prepare a product NCPO. The prepared NCPO was tested by gel permeation chromatography with the mobile phase of DMSO, and the results of test showed that the molecular weight Mn was 23 kDa and PDI was 1.20.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (1 mmol) was dissolved in 2 mL of DMF, and air was continuously filled. An obtained solution was stirred for reaction at 100° C. for 72 h. Then, a prepared crude product was diluted with DMF to about 10 mg/mL, and filtered by using a polytetrafluoroethylene filter head with a pore size of 0.45 μm, and an obtained filtrate was concentrated by using a rotary evaporator, and dialysed in a DMF solution by using a dialysis bag (molecular weight cut-off=5 kDa) for 3 days to prepare a product NCPO. The prepared NCPO was tested by gel permeation chromatography with the mobile phase of DMF, and the results of test showed that the molecular weight Mn was 8 kDa and PDI was 1.98.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (0.5 mmol) and 3,7-dihydrobenzo[1,2-b:4,5-b′]dithiophene-2,6-dione (0.5 mmol) were dissolved in 2 mL of hexamethylphosphoramide (HMPA), and duroquinone (1 mmol) was added. An obtained solution was stirred for reaction at 100° C. for 22 h. Then, the obtained solution was slowly dropwise added to 200 mL of dichloromethane, an obtained mixture was filtered, and a precipitate was collected, namely, product NCPO0.5-NCPS0.5. The prepared product was tested by gel permeation chromatography with the mobile phase of DMSO and the results of test showed that the molecular weight Mn was 12 kDa, and PDI was 2.01.
3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (0.7 mmol) and 1,5-dihexyl-5,7-dihydro-1H,3H-pyrrolo[2,3-f]indole-2,6-dione (0.3 mmol) were dissolved in 2 mL of hexamethylphosphoramide (HMPA), and hydrogen peroxide (1 mmol, a 30 wt % aqueous solution) was added. An obtained solution was stirred for reaction at 100° C. for 20 h. Then, the obtained solution was slowly dropwise added to 200 mL of dichloromethane, an obtained mixture was filtered, and a precipitate was collected, namely, product NCPO0.7-NCPN0.3. The prepared product was tested by gel permeation chromatography with the mobile phase of DMSO, and the results of test showed that the molecular weight Mn was 2.8 kDa and PDI was 1.08.
3,7-dihydrobenzo[1,2-b:4,5-b′]dithiophene-2,6-dione (0.5 mmol) and 1,5-dihexyl-5,7-dihydro-1H,3H-pyrrolo[2,3-f]indole-2,6-dione (0.5 mmol) were dissolved in 2 mL of hexamethylphosphoramide (HMPA), and iron trichloride (1 mmol) was added. An obtained solution was stirred for reaction at 100° C. for 72 h. Then, the obtained solution was slowly dropwise added to 200 mL of dichloromethane, an obtained mixture was filtered, and a precipitate was collected, namely, product NCPS0.5-NCPN0.5. The prepared product was tested by gel permeation chromatography with the mobile phase of DMSO, and the results of test showed that the molecular weight Mn was 3.0 kDa and PDI was 1.11.
The n-type conjugated polymers of Example 1 and Example 2 were adjusted to a solute concentration of 15 mg/mL with DMF (for NCPO of Example 1) and DMSO (for NCPO of Example 2), and the foregoing solutions were spin-coated to form films, and after the films were dried, the conductivity of the thin films was measured by the four-point probe method. A specific steps were as follows.
A quartz glass sheet was washed in an ultrasonic cleaner by using acetone, a special detergent for micron-level semiconductors, deionized water, and isopropanol as washing solvents in sequence, and after the washing was completed, the surface of the glass sheet was blow-dried with nitrogen, oven-dried by using an infrared lamp, and placed in a constant temperature oven for later use. Before being used, the glass sheet was bombarded with plasma in a plasma etching instrument for 10 min.
After the preparation of the glass sheet was completed, the glass sheet was placed on a heating table, heated at 110° C., transferred to a spin coater (KW-4A), and spin-coated with the foregoing prepared n-type conjugated polymer (with a mass concentration of the conjugated polymer solution of 15 mg/mL) at high speed, and the thickness of the film was measured and monitored by using a step profiler. After the formation of the film was completed, the square resistance of the film was tested by using a four-point probe conductivity tester (RTS-8 model four-point tester), and the conductivity was calculated. The results are shown in Table 1.
It can be known from Table 1 that the conjugated polymers of the present invention have high conductivity.
The n-type conjugated polymer of Example 1 was applied in an organic photovoltaic cell as an electron transport layer, and relevant device data was tested. As a comparison example, ZnO was employed as an electron transport layer at the same time and tested under the experimental conditions of the same device structure. The organic photovoltaic cell device was prepared by a conventional method, and prepared in a glove box with levels of oxygen and water being less than 1 ppm.
A structure of the organic photovoltaic cell was as follows: ITO (100 nm)/NCPO of Example 1 (or ZnO) (50 nm)/active layer (PM6:Y6=1:1.5, m/m mixed, 1 wt % diiodooctane was added) (120 nm)/molybdenum oxide (60 nm)/silver electrode (60 nm).
An effective area of a single device was 0.0516 cm2.
ZnO was purchased from Sigma-Aldrich with the catalog No. 544906.
PM6 and Y6 were purchased from VAC. Structural formulas of PM6 and Y6 are as follows:
The energy for simulating sunlight was calibrated to 100 mW/cm2 by using a silicon photoelectric diode calibrated by US National Renewable Energy Laboratory (NREL) and a KG5 filter before the test. The energy conversion efficiency of the device was measured by using a standard solar spectrum AM1.5 solar simulator (the catalog No. 91192, Oriel, USA), and current-voltage (J-V) characteristics of the photovoltaic cell device were recorded by using Keithley 2410 and Keithley 236 source-measure units, respectively.
It can be seen from Table 2 that two parameters, namely, the short-circuit current and the fill factor, of the organic photovoltaic cell in which NCPO of Example 1 is employed as an electron transport layer are more ideal than those of the organic photovoltaic cell in which ZnO is employed as an electron transport layer, resulting in higher final photoelectric conversion efficiency.
A thermoelectric test was performed on NCPO of Example 1 and Example 2.
The thermoelectric performance of a material is often described by a thermoelectric figure of merit (ZT), which is specifically calculated by using the following formula:
ZT=S2σT/κ,
PF=S2σ.
In this test, the n-type conjugated polymers of Example 1 and Example 2 were taken as examples, and used to prepare a thin film on a glass substrate by drop-casting. The conductivity and the Seebeck coefficient of the films were tested to characterize the thermoelectric performance of the film. The conductivity was tested by the four-point probe method.
The glass substrate was washed with deionized water and isopropanol in sequence, and the surface was blow-dried with nitrogen. The glass was bombarded with plasma in a plasma etching instrument for 5 min. Then, different n-type conjugated polymer solutions were drop-coated on the substrates, the substrates were annealed at 80° C. for 15 min, and the conductivity was measured. Conductivity test results are shown in Table 3.
A processing method of a device for testing the Seebeck coefficient was similar to the processing method of the device for testing the conductivity, glass was employed as a substrate, and a gold electrode was prepared by photoetching and used as a test electrode. The glass substrate was washed with deionized water and isopropanol in sequence, and the surface was blow-dried with nitrogen. The glass was bombarded with plasma in a plasma etching instrument for 5 min. Then, different n-type conjugated polymer solutions were drop-coated on the substrates, and the substrates were annealed at 80° C. for 15 min.
Two ends of the device were placed in a temperature gradient field.
Application of the polymer of the present invention in electromagnetic shielding was tested. A dielectric constant and the electromagnetic shielding performance of NCPO of Example 2 were tested by a coaxial method and a waveguide method in a band of 1-18 GHz. Experimental sample powder of NCPO of Example 2 was mixed with paraffin in a proportion by weight of 50%, and ground to prepare a powder material, and the powder material was pressed into a coaxial ring with an outer diameter of 7 mm, an inner diameter of 3.04 mm, and a thickness of 2 mm by using a mold. The sample was placed in a waveguide tube. A DR-S01 vector network analyzer was employed as a host machine. An S parameter of the sample was tested by using the network analyzer, and the reflectance and absorptance of the thin film sample were calculated based on the S parameter with reference to the paper (Review of Scientific Instruments. 2003, 74, 1098-1102), and then the electromagnetic shielding performance of the thin film sample was determined.
The electromagnetic shielding efficiency and absorption ratio of the powder material of NCPO of Example 2 are shown in
The foregoing tests indicate that the n-type conjugated polymer of the present invention can be widely applied in various organic photoelectric devices.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202110679959.2 | Jun 2021 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2021/124880 | 10/20/2021 | WO |
