Organic photosensitive molecule with spectral response reaching infrared region and application thereof

Abstract

The invention discloses an organic photosensitive molecule with spectral response reaching an infrared region. The organic photosensitive molecule has the following structural formula (I). The invention also comprises a preparation method and a performance test of the material, and an application of the material in a photoelectric detector. A photoelectric detector prepared from the organic photosensitive molecular material reaching the infrared region based on the spectral response has extremely high responsivity and extremely low dark current in a short wave infrared region, and the detection capability of the photoelectric detector on weak infrared light can be greatly improved. # imgabs0 #

Description

An organic photosensitizer molecule with spectral response reaching the infrared region and its application Technical Field

[0001] The present invention relates to the field of photoelectric materials, and in particular to an organic photosensitive molecule whose spectral response reaches the infrared region and applications thereof. Background Art

[0002] Photodetectors are a vital component of modern science and industry. With the continuous advancement of artificial intelligence, photodetection technology is gaining increasing attention from academia and industry. Photodetectors have important applications in biomedicine, fiber-optic communications, autonomous driving, night vision surveillance, and other fields. Compared to traditional inorganic photodetectors, organic photodetectors (OPDs) offer advantages such as flexibility, affordability, and lightweight. Their core performance parameters rival those of inorganic photodetectors, making them an ideal choice for next-generation flexible wearable electronics and image sensors.

[0003] Organic semiconductor materials play an important role in OPDs. As early as the end of the 20th century, Kudo, Heeger and others reported various OPD devices based on organic semiconductor materials. Compared with inorganic semiconductor materials, organic semiconductor materials have advantages such as higher absorption coefficient, adjustable absorption spectrum range, light weight, flexibility, large-area solution processing, easy array device preparation and circuit integration. Due to the continuous development of new narrow bandgap polymers and small molecules, OPDs also show excellent light detection performance in the short-wave infrared region. From a material perspective, the key condition for manufacturing OPDs with spectral response extending into the near-infrared region is how to design and synthesize active layer materials with a sufficiently narrow optical bandgap. Therefore, designing and synthesizing an organic semiconductor material with an ultra-narrow bandgap and good optoelectronic properties is very important for realizing a truly organic photodetector with good device performance in a response range exceeding 1000nm.

[0004] In previous work, we have reported a class of organic photosensitizers with spectral response reaching the infrared region in CN114891027A. On the core of its thienocyclopentadiene, a spirofluorene-like group based on a five-membered ring was grafted, which had certain light response characteristics in the near-infrared band. However, due to the influence of the insufficient electron-donating ability of the central core, the insufficient obvious spiral conjugation effect, and the unreasonable insufficiency of the molecular stacking pattern, although the organic photosensitizers based on the five-membered ring spirofluorene-like group have achieved certain breakthroughs in absorption spectrum and device photoelectric response, the photoelectric corresponding range is still mainly confined to the wavelength range of 1100nm, which affects the application potential of the device performance of the OPD device to a certain extent. Based on this, the present invention further designs and prepares a series of novel organic photosensitizers with spectral response reaching the infrared region, broadens the absorption spectrum of the material, improves the photoelectric response and photoelectric response range of the device, and has important research significance and a wide range of application scenarios in optoelectronic fields such as OPD.

[0005] Summary of the Invention

[0006] The present invention relates to an organic photosensitive molecule with a spectral response extending into the infrared region, as well as methods for preparing the material, testing its performance, and its application in photodetectors. Photodetectors fabricated from this type of organic photosensitive molecule with a spectral response extending into the infrared region exhibit extremely high responsivity in the short-wave infrared region and extremely low dark current, significantly enhancing the detector's ability to detect weak infrared light.

[0007] The term "bulk heterojunction" in the present invention refers to an interpenetrating network structure with nanoscale phase separation formed by blending donor and acceptor materials.

[0008] The term "donor material" in the present invention refers to a P-type semiconductor material.

[0009] The term "acceptor material" in the present invention refers to an N-type semiconductor material.

[0010] The term "band gap" in the present invention refers to the optical band gap of a semiconductor material, and its value is obtained by dividing 1240 by the cut-off wavelength of the absorption edge of the semiconductor material.

[0011] The term "spectral response region" in the present invention refers to the effective operating optical band of the photodiode and its array, and is defined as the wavelength range where the external quantum efficiency is greater than 10% of the peak efficiency.

[0012] The term "active layer" in the present invention refers to a thin film layer in a device structure that is responsible for absorbing photons and generating free electrons and holes.

[0013] The term "aromatic group" as used herein refers to an aromatic ring system containing a conjugated structure, which may be partially or fully conjugated. Aromatic groups may be independently connected to adjacent units by bonding or fusion. They may contain carbon atoms, or some of their carbon atoms, independently substituted with heteroatoms such as N, O, S, or Se; the N and S atoms may be independently oxidized; and the nitrogen atoms may be independently substituted or unsubstituted, and may be independently quaternized.

[0014] One object of the present invention is to provide an organic photosensitive molecule with a spectral response extending into the infrared region. It has the following structural formula (I):

[0015] in,

[0016] n is independently selected from 1, 2, 3 up to 20;

[0017] Ar is independently selected from substituted or unsubstituted aromatic groups, or is absent;

[0018] K is independently selected from substituted or unsubstituted aromatic or cycloalkyl groups, or is absent;

[0019] E is independently selected from substituted or unsubstituted aromatic or cycloalkyl, or is absent;

[0020] R1 is independently selected from one or more of a hydrogen atom, an ester group, a hydroxyl group, a nitro group, a halogen group, a cyano group, an alkyl group, an alkyl derivative, an alkylene group, an alkylene derivative, an aralkyl group, and an aralkyl derivative;

[0021] One or more carbon atoms on the alkyl derivative, alkylene derivative or aralkyl derivative are substituted by one or more of an oxygen atom, an amino group, a sulfone group, a carbonyl group, an aryl group, an alkene group, an alkyne group, an ester group, a cyano group or a nitro group;

[0022] and / or

[0023] One or more hydrogen groups on the alkyl derivative, alkylene derivative or aralkyl derivative are substituted by one or more of halogen, hydroxyl, amino, carboxyl, cyano, nitro, aryl, alkene or alkyne groups;

[0024] X is independently selected from C, S, O, Se or N-R1;

[0025] Y is independently selected from C, S, O, Se or N-R1;

[0026] A is independently selected from electron acceptor units;

[0027] Any one or more hydrogen atoms in the structural formula (I) are not substituted by other atoms and / or groups, or are independently substituted by protium, deuterium or tritium atoms.

[0028] Furthermore, the A is selected from one or more of the following structures:

[0029] in,

[0030] Ar' is independently selected from substituted or unsubstituted aromatic groups, or is absent;

[0031] R4 is independently selected from hydrogen or a substituted or unsubstituted alkyl group, a substituted or unsubstituted aromatic group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio group, a substituted or unsubstituted silyl group or a substituted or unsubstituted ester group;

[0032] Y is independently selected from S, O, Se or N-R4;

[0033] Any one or more hydrogen atoms in the structure A are not replaced by other atoms and / or groups, or are independently replaced by protium, deuterium or tritium atoms.

[0034] Preferably, E is selected from one or more phenyl or thienyl groups, wherein one or more hydrogen atoms on the phenyl or thienyl groups may be substituted with one or more of an ester group, a hydroxyl group, a nitro group, a halogen group, a cyano group, an alkyl group, an alkyl derivative, an alkylene group, an alkylene derivative, an aralkyl group, or an aralkyl derivative. The multiple phenyl or thienyl groups may be interconnected in a linked ring or fused ring structure.

[0035] The term "alkyl" in the present invention refers to a branched or straight-chain saturated aliphatic hydrocarbon group having a specified number of carbon atoms. Examples of alkyl groups include straight-chain or branched alkyl groups, and straight-chain alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, n-heneicosyl, n-docosyl, n-tricosyl, and n-tetracosyl; branched-chain alkyl groups include, but are not limited to, isopropyl, isobutyl, tert-butyl, isopentyl, 1-Hexyl, 1-Hexyl, 1-Hexyl, 1-Hexyldecyl, 2-Hexyldecyl, 3-Hexylundecyl, 2-octyldecyl, 2-octyldodecyl, 3-octyltridecyl, 2-decyldodecyl, 2-decyltetradecyl, 3-decylpentadecyl, 2-dodecylhexadecyl, 4-octyltetradecyl, 4-decylhexadecyl, 4-hexyldecyl, 4-octyldodecyl, 4-decyltetradecyl, 4-dodecylhexadecyl and the like.

[0036] The term "alkoxy" as used herein refers to -O-alkyl, wherein the definition of alkyl is consistent with the definition of alkyl described above. Examples of alkoxy include, but are not limited to, methoxy, ethoxy, propoxy, n-butoxy, n-pentoxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, n-undecyloxy, n-dodecyloxy, 2-ethylhexyloxy, 2-ethyloctyloxy, 2-butylhexyloxy, 2-hexyloctyloxy, 4-hexyldecyloxy, 3-hexylundecyloxy, 2-octyldecyloxy, 2-octyldodecyloxy, 3-octyltridecyloxy, 2-decyldodecyloxy, 2-decyltetradecyloxy, 3-decylpentadecyloxy, 2-dodecylhexadecyloxy, 4-octyltetradecyloxy, 4-decylhexadecyloxy, 4-hexyldecyloxy, 4-octyldodecyloxy, 4-decyltetradecyloxy, 4-dodecylhexadecyloxy, and the like;

[0037] The term "alkylthio" herein refers to -S-alkyl, wherein the definition of alkyl is the same as that of alkyl above. Examples of alkylthio groups include, but are not limited to, methylthio, ethylthio, propylthio, n-butylthio, n-pentylthio, n-hexylthio, n-heptylthio, n-octylthio, n-nonylthio, n-decylthio, n-undecylthio, n-dodecylthio, 2-ethylhexylthio, 2-ethyloctylthio, 2-butylhexylthio, 2-hexyloctylthio, 4-hexyldecylthio, 3-hexylundecylthio, 2-octyldecylthio, 2-octyldodecylthio, 3-octyltridecylthio, 2-decyldodecylthio, 2-decyltetradecylthio, 3-decylpentadecylthio, 2-dodecylhexadecylthio, 4-octyltetradecylthio, 4-decylhexadecylthio, 4-hexyldecylthio, 4-octyldodecylthio, 4-decyltetradecylthio, 4-dodecylhexadecylthio, and the like;

[0038] The term "silyl" in the present invention refers to -Si-alkyl, wherein the definition of alkyl conforms to the definition of alkyl described above. Examples of silyl include, but are not limited to, methylsilane, ethylsilane, propylsilane, n-butylsilane, n-pentylsilane, n-hexylsilane, n-heptylsilane, n-octylsilane, n-nonylsilane, n-decylsilane, n-undecylsilane, n-dodecylsilane, trimethylhexylsilane, trimethylheptylsilane, trimethyloctylsilane, trimethylnonylsilane, trimethyldecylsilane, trimethylhexylsilane, hexylmethylbis(trimethylsiloxy)silane, heptylmethylbis(trimethylsiloxy)silane, octylmethylbis(trimethylsiloxy)silane, nonylmethylbis(trimethylsiloxy)silane, decylmethylbis(trimethylsiloxy)silane, undecylmethylbis(trimethylsiloxy)silane, and dodecylmethylbis(trimethylsiloxy)silane.

[0039] Furthermore, the K is independently selected from a substituted or unsubstituted monoaromatic group, or a substituted or unsubstituted polyaromatic group.

[0040] Further, the aromatic group includes but is not limited to common five-membered ring or six-membered ring structures, such as phenyl, biphenyl, indanyl, naphthyl, thienyl, furyl, pyrrolyl, pyridyl, imidazolyl, acridinyl, azetidinyl, acridinyl, benzimidazolyl, benzofuranyl, benzothiofuranyl, benzothiophenyl, benzoxazolyl, benzoxazolinyl, benzothiazolyl, benzotriazolyl, benzotetrazolyl, benzisoxazolyl, benzisothiazolyl, benzimidazolinyl, carbazolyl, pyrimidinyl, pyrrolidinyl, pyrrolinyl, 2-pyrrolidonyl, 2H-pyrrolyl, quinazolinyl, quinolinyl, 4H-quinolizinyl, One or more of quinoxalinyl, quinuclidinyl, tetrazolyl, tetrahydrofuranyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl, 6H-1,2,5-thiadiazinyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, thianthrenyl, thiazolyl, thienyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, triazinyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,5-triazolyl, 1,3,4-triazolyl and xanthenyl, quinolinyl, isoquinolinyl, phthalazinyl, quinazolinyl.

[0041] Furthermore, the polyvalent aromatic group includes but is not limited to one or more of a biaryl group, a fused aromatic group, and a spiro aromatic group.

[0042] The K portion in the present invention can be another one or more linked rings or condensed ring structures attached to the thiophene ring. The linked rings or condensed rings can be substituted or unsubstituted, and can be an aromatic ring without any heteroatoms, or an aromatic heterocycle containing one or more heteroatoms (such as S, O, NR, Se, etc.).

[0043] The specific molecular structure described in structural formula (I) of the present invention includes all derivative structures based on the same core structure (i.e., a six-membered ring spirofluorene structure), which may be, but is not limited to, any of the following structures:

[0044] wherein R and R1 are independently selected from one or more of a hydrogen atom, an ester group, a hydroxyl group, a nitro group, a halogen group, a cyano group, an alkyl group, an alkyl derivative, an alkylene group, an alkylene derivative, an aralkyl group, and an aralkyl derivative;

[0045] One or more carbon atoms on the alkyl derivative, alkylene derivative or aralkyl derivative are substituted by one or more of an oxygen atom, an amino group, a sulfone group, a carbonyl group, an aryl group, an alkene group, an alkyne group, an ester group, a cyano group or a nitro group;

[0046] and / or

[0047] One or more hydrogen groups on the alkyl derivative, alkylene derivative or aralkyl derivative are substituted by one or more of halogen, hydroxyl, amino, carboxyl, cyano, nitro, aryl, alkene or alkyne groups.

[0048] Specifically, the present invention introduces a six-membered spirofluorene structure into the conjugated backbone. This spirofluorene structure is a typical spirocyclic structure with advantages such as high thermal stability, suitable frontier orbital energy levels, and a rational molecular stacking pattern. This rational stacking pattern has a significant impact on the thin-film absorption range and carrier transport capacity of the molecular host, facilitating the construction of non-fullerene small molecule receptors with a broader spectral response.

[0049] In addition, by modifying the six-membered ring spirofluorene unit with different substituents and substituent atoms, the solubility, energy level distribution, absorption range and stacking mode of the molecule can be further affected, thereby achieving different photoelectric properties.

[0050] Another object of the present invention is to provide a polymer material containing the above-mentioned infrared-responsive organic photosensitive molecules as copolymer units in its molecular structure.

[0051] The infrared responsive organic photosensitive molecules described in the present invention can be used as a part of copolymerization units in a polymer structure and applied to polymer materials, so that the polymer materials contain the molecular structure of the infrared responsive organic photosensitive molecules.

[0052] Another object of the present invention is to provide the use of the above-mentioned organic photosensitive molecules with spectral response reaching the infrared region in organic optoelectronic devices.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] 1. The core of the present invention is a derivative of thienocyclopentadiene with a six-membered spiro structure. While ensuring the excellent electron-donating performance and planar structure of the molecular skeleton, the introduction of the six-membered spiro structure increases the solubility of the material, promotes the energy level splitting of the material, and forms a delocalization of π electrons in a larger range; and then after being connected with the acceptor A unit with strong electron-withdrawing ability, a significant DA structure is formed, and the absorption spectrum can cover the infrared region. It is a type of organic photosensitive material that can achieve infrared spectrum coverage.

[0055] 2. Thienocyclopentadiene derivatives with a six-membered ring spiro structure at their cores exhibit distinct three-dimensional structures, which facilitate the formation of intermolecular aggregation. The six-membered ring spiro structure further enhances the steric hindrance of the molecular core, promoting a more rational aggregation pattern. This further red-shifts the absorption spectrum of organic photosensitive molecules with spectral responses in the infrared region and promotes charge transport.

[0056] 3. Thienocyclopentadiene derivatives with a six-membered ring spiro structure at the core have more reasonable energy level splitting and spiro conjugation effect. In addition, the three-dimensional structure formed can form an intermolecular charge transfer channel within the three-dimensional space, while ensuring that the spectral response reaches the infrared region, achieving a higher photoelectric response.

[0057] 4. By modifying the six-membered spirofluorene unit with different substituents and atoms, the molecular solubility, energy level distribution, absorption range, and stacking pattern of thienocyclopentadiene derivatives with a six-membered spiro core can be further optimized. Precisely controlling the six-membered spiro structure can further alter the absorption spectrum and achieve diverse optoelectronic properties.

[0058] 5. The organic photosensitive molecules of the present invention, whose spectral response reaches the infrared region, are applied to optoelectronic devices, especially organic infrared detectors, and have excellent responsiveness characteristics, reaching the optimal level of detection performance of near-infrared organic photodetectors based on small molecule organic photosensitive materials that have been reported so far. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] FIG1 shows the UV-visible absorption spectra of Comparative Examples D1-D5;

[0060] FIG2 shows the UV-visible absorption spectra of Examples M1, M2, M4, and M8;

[0061] FIG3 shows the UV-visible absorption spectra of Examples M11, M15, M21, and M25;

[0062] FIG4 shows device EQE diagrams based on comparative examples D1-D4;

[0063] FIG5 shows device EQE diagrams based on embodiments M1, M2, M4, and M8;

[0064] FIG6 shows device EQE diagrams based on embodiments M11, M15, M21, and M25;

[0065] FIG7 shows a dark current diagram of devices based on comparative examples D1-D4;

[0066] FIG8 shows a dark current diagram of devices based on embodiments M1, M2, M4, and M8;

[0067] FIG9 shows a graph of dark current of devices based on embodiments M11, M15, M21, and M25;

[0068] FIG10 shows a device responsivity diagram based on comparative examples D1-D4;

[0069] FIG11 shows a device responsivity diagram based on embodiments M1, M2, M4, and M8;

[0070] FIG12 shows a device responsivity diagram based on embodiments M11, M15, M21, and M25;

[0071] FIG13 shows a graph of device specific detectivity based on comparative examples D1-D4;

[0072] FIG14 shows a graph of device specific detectivity based on embodiments M1, M2, M4, and M8;

[0073] FIG15 shows a graph of device specific detectivity based on embodiments M11, M15, M21, and M25; DETAILED DESCRIPTION

[0074] In order to more clearly illustrate the technical solution of the present invention, the following preparation examples and examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the preparation examples and examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0075] Example 1

[0076] An organic photosensitive molecule M1, whose molecular structure is shown in the figure below:

[0077] The preparation method of the above-mentioned organic photosensitive molecules is shown in the figure below:

[0078] Synthesis of compound 1:

[0079] 2-Bromo-triphenylamine (30 mmol) was added to 200 mL of anhydrous n-hexane, followed by the slow addition of n-butyllithium (33 mmol). The reaction was refluxed under N2 protection for 1.5 h. 100 mL of anhydrous THF was added to the reaction flask, which was cooled at -80°C for 15 min. 4H-cyclopenta[1,2-b:5,4-b']dithiophen-4-one (30 mmol) was slowly added, and the mixture was stirred overnight at room temperature. The reaction solution was extracted, washed with water, dried, filtered, and spin-dried. Finally, column chromatography using PE:DCM = 1:1 (v / v) as the eluent afforded a white solid, which was then directly used in the next step (yield = 75%).

[0080] Synthesis of compound 2:

[0081] Compound 1 (20 mmol) was added to 250 mL of dichloromethane, followed by the addition of boron trifluoride etherate (24 mmol). The reaction was allowed to react at room temperature for 40 min. The reaction solution was extracted, washed with water, dried, filtered, and spin-dried. Finally, column chromatography using PE:DCM = 6:1 (v / v) as the eluent afforded a light yellow solid (yield = 66%).

[0082] 1HNMR(500MHz,Chloroform-d)δ7.73-7.65(m,2H),7.60-7.53(m,1H),7.50-7.43( m,2H),7.17(d,J=5.0Hz,2H),7.05-6.92(m,4H),6.70-6.62(m,4H),6.37(m,2H).

[0083] Synthesis of compound 3:

[0084] Compound 2 (10 mmol) was added to 150 mL of anhydrous THF and cooled at -80°C under N2 protection for 15 min. n-Butyl lithium (23 mmol) was slowly added dropwise. After reacting for 1 h, trimethyltin chloride (25 mmol) was added and stirred at room temperature overnight. The reaction solution was extracted, washed with water, dried, filtered, and spin-dried to obtain compound 3, which was directly carried out to the next step.

[0085] Synthesis of compound 4:

[0086] Compound 3 (5 mmol), 5-bromo-4-((2-hexyldecyl)alkoxy)thiophene-2-carbaldehyde (12 mmol), and Pd(PPh3)4 (1 mmol) were added to 30 mL of toluene and refluxed overnight under N2 protection. The reaction solution was cooled to room temperature, dried, and purified by column chromatography using PE:DCM = 1:1 (v / v) as the eluent to obtain a blue-purple solid (yield = 82%).

[0087] 1 HNMR(500MHz,Chloroform-d)=δ9.73(s,2H),7.73-7.77(m,2H),7.59-7.63(m,1H),7.44-7.50(m,4H),7.33(s,2H),6.98-7.03(m,2H) ,6.65-6.67(m,4H),6.40-6.42(d,J=10Hz,2H),4.07-4.09(d,J=10Hz,4H),1.87-1.93(m,2H),1.26-1.39(m,48H),0.84-0.90(m,12H).

[0088] Synthesis of M1

[0089] Compound 4 (3 mmol), 5,6-difluoro-3-(dicyanomethylene)indone (10 mmol), and 1 mL of pyridine were added to 50 mL of chloroform and reacted at 50°C under N2 protection for 16 h. The reaction solution was cooled to room temperature, dried by spin drying, and purified by column chromatography using PE:DCM = 1:2 as the eluent to obtain a bluish-black solid. The final product, M1, was then recrystallized (yield = 75%).

[0090] 1 HNMR(500MHz,Chloroform-d)=δ8.67(s,2H),8.48-8.52(m,2H),7.78-7.81(m,2H),7.61-7.66(m,5H),7.57(s,2H),7.45(s,2H),7.00-7.04( m,2H),6.66-6.69(m,4H),6.43-6.45(d,J=10Hz,2H),4.13-4.14(d,J= 7.5Hz,4H),1.93-1.97(m,2H),1.27-1.60(m,48H),0.84-0.91(m,12H).

[0091] Other embodiments

[0092] A series of organic photosensitive molecules are listed below, and their structures are shown in Table 1. The preparation method is the same as that of Example 1, except that the relevant monomers are replaced. Therefore, the preparation methods are all known technologies and are not listed here one by one.

[0093] The total yield is calculated by taking the initial raw material as the basis, calculating it as 100%, and then synthesizing several intermediate products until the yield of the final product.

[0094] The total yield is the product of the yield of the intermediate product / final product in each step of the process, starting from the reaction of the initial raw materials.

[0095] Table 1 Molecular structure and total yield of monomers related to the examples

[0096] Comparative Example

[0097] Based on the preparation methods of the Examples, a set of comparative examples was prepared. The raw materials and preparation methods of the comparative examples were the same as those of the Examples, with the only difference being that one or more groups in the monomers were replaced with other groups. The results are shown in Table 2.

[0098] Table 2 Comparative Examples Related Monomer Molecular Structure and Total Yield

[0099] Test Case

[0100] The photophysical and electrochemical performance tests were performed on the above-mentioned Examples M1, M2, M4, M8, M11, M15, M21, M25 and Comparative Examples D1, D2, D3, D4, and D5. The OPD devices were prepared and the basic performance was characterized for the relevant materials. The performance tests included:

[0101] (1) Material absorption spectrum testing;

[0102] (2) Testing of the electrochemical energy level of materials;

[0103] (3) Testing of device dark current;

[0104] (4) Device EQE testing;

[0105] (5) Calculation of device responsivity;

[0106] (6) Calculation of device specific detection rate.

[0107] Since comparative example D5 has almost no response in the spectral region exceeding 1000 nm, the preparation and characterization of the near-infrared OPD device were not performed.

[0108] The above test methods are all well known to those skilled in the art.

[0109] In this test example, the specific structure of the device is silver / molybdenum trioxide / active layer (PTB7-Th: organic photosensitive molecule = 1:1.5, w / w) / zinc oxide / ITO.

[0110] The test results are shown in Table 3.

[0111] Please refer to Figures 1-15 for the relevant characterization images of the small molecule receptors related to the above examples and comparative examples.

[0112] Table 3. Absorption, energy level, responsivity R and specific detectivity D* of comparative examples D1-D5 and examples M1, M2, M4, M8, M11, M15, M21, and M25.

[0113] It can be seen from Table 1 and Figures 1-15 that the product disclosed in the technical solution of the present invention has a more obvious and intense light response in the near-infrared band (at 1060nm and 1150nm) compared to the comparative example, and has important research significance and a wide range of application scenarios in optoelectronic fields such as OPD. At the same time, it is more suitable for application in unique environments such as biological imaging, remote communication, and night surveillance.

Claims

1. An organic photosensitive molecule with a spectral response reaching the infrared region, characterized in that: The organic photosensitive molecule with a spectral response reaching the infrared region has the following structural formula (I): in, n is independently selected from 1, 2, 3 to 20; Ar is independently selected from substituted or unsubstituted aromatic groups, or is absent; K is independently selected from substituted or unsubstituted aromatic or cycloalkyl, or is absent; E is independently selected from substituted or unsubstituted aromatic or cycloalkyl, or is absent; R1 is independently selected from one or more of a hydrogen atom, an ester group, a hydroxyl group, a nitro group, a halogen group, a cyano group, an alkyl group, an alkyl derivative, an alkylene group, an alkylene derivative, an aralkyl group, and an aralkyl derivative; One or more carbon atoms on the alkyl derivative, alkylene derivative or aralkyl derivative are substituted by one or more of oxygen atoms, amino groups, sulfone groups, carbonyl groups, aryl groups, olefin groups, alkynyl groups, ester groups, cyano groups and nitro groups; and / or One or more hydrogen groups on the alkyl derivative, alkylene derivative or aralkyl derivative are replaced by one or more of halogen, hydroxyl, amino, carboxyl, cyano, nitro, aryl, alkene or alkyne groups; X is independently selected from C, S, O, Se or N-R1; Y is independently selected from C, S, O, Se or N-R1; A is independently selected from electron acceptor units; Any one or more hydrogen atoms in the structural formula (I) are not substituted by other atoms and / or groups, or are independently substituted by protium, deuterium or tritium atoms.

2. The organic photosensitive molecule with a spectral response reaching the infrared region according to claim 1, characterized in that: The A is selected from one or more of the following structures: in, Ar' is independently selected from substituted or unsubstituted aromatic groups, or is absent; R4 is independently selected from hydrogen or substituted or unsubstituted alkyl, substituted or unsubstituted aromatic, substituted or unsubstituted alkoxy, substituted or unsubstituted alkylthio, substituted or unsubstituted silyl or substituted or unsubstituted ester; Y is independently selected from S, O, Se or N-R4; Any one or more hydrogen atoms in the A structure are not replaced by other atoms and / or groups, or are independently replaced by protium, deuterium or tritium atoms.

3. The organic photosensitive molecule with a spectral response reaching the infrared region according to claim 1, characterized in that: The R1 is independently selected from a hydrogen atom, a substituted or unsubstituted C1-C24 straight chain or branched alkyl group, a substituted or unsubstituted C1-C24 straight chain or branched alkoxy group, a substituted or unsubstituted C1-C24 straight chain or branched alkylthio group, and a substituted or unsubstituted C1-C24 straight chain or branched silyl group.

4. The organic photosensitive molecule having a spectral response reaching the infrared region according to claim 1, characterized in that: The K is independently selected from a substituted or unsubstituted monoaromatic group, or a substituted or unsubstituted polyaromatic group, characterized in that the K is selected from one or more of the following structures: in, R1 and R2 each independently represent a hydrogen atom, an ester group, a hydroxyl group, a nitro group, a halogen group, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio group, a substituted or unsubstituted silyl group, or a substituted or unsubstituted ester group; X is C, S, O, Se, N-R1; Y is C, S, O, Se, N-R1; Any one or more hydrogen atoms in the K structure are not replaced by other atoms and / or groups, or are independently replaced by protium, deuterium or tritium atoms.

5. The organic photosensitive molecule with a spectral response reaching the infrared region according to claim 1, characterized in that: The aromatic group includes, but is not limited to, phenyl, biphenyl, indanyl, naphthyl, thienyl, furanyl, pyrrolyl, pyridinyl, imidazolyl, acridinyl, azetidinyl, azinyl, benzimidazolyl, benzofuranyl, benzothiofuranyl, benzothiophenyl, benzoxazolyl, benzoxazolinyl, benzothiazolyl, benzotriazolyl, benzotetrazolyl, benzisoxazolyl, benzisothiazolyl, benzimidazolinyl, carbazolyl, pyrimidinyl, pyrrolidinyl, pyrrolinyl, 2-pyrrolidinone, 2H-pyrrolyl, quinazolinyl, quinolinyl, 4H-quinolizinyl, quinoxalinyl, quinuclidine, One or more of tetrazolyl, tetrahydrofuranyl, tetrahydroisoquinolyl, tetrahydroquinolyl, 6H-1,2,5-thiadiazinyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, thianthrenyl, thiazolyl, thienyl, thiazolyl ...

6. The organic photosensitive molecule with a spectral response reaching the infrared region according to claim 1, characterized in that: The polyvalent aromatic group includes, but is not limited to, one or more of a biaromatic group, a fused aromatic group, and a spiro aromatic group.

7. A polymer receptor having a molecular structure containing an organic photosensitive molecule having a spectral response reaching the infrared region as described in any one of claims 1 to 7 as a copolymer unit.

8. Use of the organic photosensitive molecule having a spectral response reaching the infrared region as claimed in any one of claims 1 to 7 in optoelectronic devices.

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