Catechol-based organic semiconductor material, and preparation method therefor and use thereof

Abstract

Disclosed in the present invention are a catechol-based organic semiconductor material, and a preparation method therefor and the use thereof. The structural formula thereof is (I), and R is pyridyl. The present invention exhibits an n-type doping electronic effect on monolayer MoS2, specifically, a monolayer MoS2 field-effect transistor device treated with the material of the present invention exhibits a current density that is increased by more than 6 times compared to that before treatment, making it effectively applicable to field-effect transistors based on two-dimensional materials.

Description

A catechol-based organic semiconductor material, its preparation method and application

[0001] Cross-references to related applications

[0002] This application claims priority to and is based on Chinese Patent Application No. 2025103712059, filed with the China National Intellectual Property Administration on March 27, 2025, entitled "A Catechol-based Organic Semiconductor Material and Its Preparation Method and Application", the contents of which are incorporated herein by reference. Technical Field

[0003] This invention belongs to the field of materials technology, specifically relating to a catechol-based organic semiconductor material, its preparation method, and its application. Background Technology

[0004] Monolayer transition metal dichalcogenides (TMDs) are ideal candidates for transparent and wearable electronic and optoelectronic devices due to their moderate band gap, high carrier mobility, efficient light absorption properties, and excellent flexibility and transparency. Furthermore, TMDs possess atomically flat surfaces without dangling bonds and extremely thin thicknesses, which not only facilitates excellent heterogeneous contacts but also effectively suppresses short-channel effects, making them highly suitable for future nanoscale electronic and optoelectronic devices. For example, ideal field-effect transistors based on MoS2 channels are theoretically expected to achieve more than 10-1 9 Current switching ratio, 410cm at room temperature 2 V -1 s -1 The carrier mobility, and close to the ideal 60 Mv / decade. -1 The subthreshold swing. These characteristics give TMDs great potential in developing next-generation flexible devices.

[0005] Despite the unique and superior properties of TMDs (Transient Metal Disks), their controllable regulation using traditional semiconductor technologies remains a significant challenge. Current methods primarily employ physical or chemical approaches to modulate the optoelectronic properties of TMDs at the atomic or molecular level. Atomic-level modulation mainly utilizes elemental substitution doping strategies, introducing different metal or non-metal atoms into the TMD lattice through methods such as chemical vapor deposition. However, this method can damage the TMD surface and introduce defects, affecting charge transport efficiency. Molecular-level modification involves methods like thermal evaporation, spin coating, solution casting, and immersion. These methods primarily use physical adsorption to immobilize small molecules or polymers on the TMD surface, utilizing charge transfer between the organic small molecule or polymer donor or acceptor and the TMD to modulate its optoelectronic properties. Since no specific interfacial interaction is formed between the molecules or polymers and the TMD, environmental changes can easily cause molecules to desorb from the TMD surface, thus affecting device stability.

[0006] How to achieve long-term stable control of the electronic properties of TMDs through strong interfacial interactions without destroying the crystal structure of TMDs or sacrificing their inherent properties is an extremely challenging problem. Summary of the Invention

[0007] The purpose of this invention is to overcome the defects of the prior art and provide a catechol-based organic semiconductor material.

[0008] Another object of the present invention is to provide a method for preparing the above-mentioned catechol-based organic semiconductor material.

[0009] Another object of the present invention is to provide the application of the above-mentioned catechol-based organic semiconductor material.

[0010] The technical solution of the present invention is as follows:

[0011] A catechol-based organic semiconductor material, characterized in that: its structural formula is as follows Where R is pyridinyl.

[0012] Its structural formula is

[0013] The preparation method of the above-mentioned catechol-based organic semiconductor materials includes the following synthetic route:

[0014] (1)

[0015] (2)

[0016] (3)

[0017] In a preferred embodiment of the present invention, the following steps are included:

[0018] (1) Under a nitrogen atmosphere, 2,7-dibromofluorene and 4-(bromomethyl)pyridine were used as raw materials, tetrabutylammonium bromide was used as a phase transfer catalyst, and 50wt% sodium hydroxide solution and tetrahydrofuran were used as solvents to react to obtain intermediate a;

[0019] (2) Using intermediate a obtained in step (1) and pinacol 3,4-dimethoxyphenylboronic acid as raw materials, with tetrahydrofuran as solvent, tetra(triphenylphosphine)palladium as catalyst and potassium carbonate as base, the Suzuki reaction was carried out under a protective atmosphere to obtain intermediate b.

[0020] (3) Dissolve the intermediate b obtained in step (2) in ultra-dry dichloromethane, and add a dichloromethane solution of boron tribromide dropwise under stirring to carry out the reaction. After the reaction is completed, quench the reaction and recrystallize to obtain the catechol-based organic semiconductor material.

[0021] More preferably, in step (1), the molar ratio of 2,7-dibromofluorene, 4-(bromomethyl)pyrene, tetrabutylammonium bromide and sodium hydroxide is 1:2.5-3:0.3:10-20, the volume ratio of sodium hydroxide solution to tetrahydrofuran is 2-4:1, the reaction temperature is 35-50℃, and the time is 10-12h.

[0022] More preferably, in step (2), the molar ratio of intermediate a, 3,4-dimethoxyphenylboronic acid pinacol ester, tetrakis(triphenylphosphine)palladium and potassium carbonate is 1:2-2.5:0.05-0.1:3-5, the volume ratio of sodium hydroxide solution to tetrahydrofuran is 2-4:1, the temperature of the Suzuki reaction is 70-80℃, and the time is 10-12h.

[0023] More preferably, in step (3), the molar ratio of intermediate b to boron tribromide is 1:8-12, the reaction temperature is -40 to -20℃, and the reaction time is 4-10h.

[0024] More preferably, the solvent for the quenching reaction is water or methanol, and the recrystallization is specifically recrystallization with n-hexane or methanol 3-5 times.

[0025] The above-mentioned catechol-based organic semiconductor materials are used in the fabrication of field-effect transistors based on two-dimensional materials.

[0026] A field-effect transistor based on two-dimensional materials, having the aforementioned catechol-based organic semiconductor material.

[0027] The beneficial effects of this invention are:

[0028] 1. The molecular structure of the present invention contains a catechol group, which can form a strong interaction with the surface of a two-dimensional material, enabling the molecule to be stably adsorbed on the surface of the two-dimensional material, thereby enabling long-term and stable regulation of the semiconductor properties of the two-dimensional material.

[0029] 2. The molecular structure of this invention contains a planar aromatic ring fluorene group, which can enhance the adsorption of the molecule on the surface of monolayer MoS2. In addition, the methylene group of the fluorene ring can be used to modify and regulate the molecule using different side groups R.

[0030] 3. The specific R groups in the molecular structure of the present invention can not only regulate the solubility of the molecule in organic solvents, but also regulate its interaction with the surface of two-dimensional materials by affecting the molecular configuration, energy level distribution and dipole moment, thereby regulating the adsorption performance of the molecule on the surface of two-dimensional materials.

[0031] 4. This invention provides an n-type doping electronic effect to monolayer MoS2. Specifically, the current density of monolayer MoS2 field-effect transistors treated with this invention is increased by more than 6 times compared to the untreated state, making it well applicable to field-effect transistors based on two-dimensional materials.

[0032] 5. The preparation process of the present invention is simple and low in cost, and meets the requirements for large-scale preparation. Attached Figure Description

[0033] Figure 1 is the 1H NMR spectrum of intermediate I-a prepared in Example 1 of the present invention.

[0034] Figure 2 is the 1H NMR spectrum of intermediate I-b prepared in Example 1 of this invention.

[0035] Figure 3 is the 1H NMR spectrum of catechol-based organic semiconductor material I (WN-OH) prepared in Example 1 of this invention.

[0036] Figure 4 shows the Raman spectra of monolayer MoS2 before and after treatment with catechol-based organic semiconductor material I (WN-OH) prepared in Example 1 in Example 2 of the present invention.

[0037] Figure 5 shows the photoluminescence spectra of monolayer MoS2 before and after treatment with catechol-based organic semiconductor material I (WN-OH) prepared in Example 1 in Example 2 of the present invention.

[0038] Figure 6 shows the transfer characteristic curves of a monolayer MoS2 field-effect transistor device before and after treatment with catechol-based organic semiconductor material I (WN-OH) prepared in Example 1 according to Example 2 of the present invention. Detailed Implementation

[0039] The technical solution of the present invention will be further explained and described below with reference to specific embodiments and accompanying drawings.

[0040] Example 1: Preparation of Catechol-based Organic Semiconductor Material I

[0041] (1) Preparation of intermediate I-a:

[0042] The synthetic route for this step is as follows:

[0043] Specifically, under a nitrogen atmosphere, 2,7-dibromofluorene (3.24 g, 10.0 mmol) and tetrabutylammonium bromide (967.1 mg, 3.0 mmol) were weighed into a Schlenk reaction flask. Then, 30 mL of sodium hydroxide solution (50 wt%) was added to the reaction flask. After heating the reaction system to 50 °C for 1 h, 4-(bromomethyl)pyridine (4.3 g, 25.0 mmol) was dissolved in 10 mL of tetrahydrofuran and added to the reaction system. The system was kept at 50 °C for 10 h. After the reaction was completed, the mixture was extracted with dichloromethane and saturated NaCl solution. The organic phase was dried with anhydrous Na₂SO₄, and excess solvent was removed using a rotary evaporator to obtain the crude product. The crude product was recrystallized from methanol and n-hexane to obtain a green solid, namely intermediate I-a. The NMR data of intermediate I-a are shown in Figure 1, and are as follows: 1 H NMR (500MHz, CDCl3) δ 8.51 (s, 4H), 7.64 (d, J=1.5Hz, 2H), 7.39 (dd, J=8.1, 1.6Hz, 2H), 7.20 (d, J=8.1Hz, 2H), 6.65 (s, 4H), 3.35 (s, 4H).

[0044] (2) Preparation of intermediate I-b:

[0045] The synthetic route for this step is as follows:

[0046] Specifically, under a nitrogen atmosphere, intermediate I-a (506.2 mg, 1.0 mmol), 3,4-dimethoxyphenylboronic acid pinacol ester (660.3 mg, 0.40 mmol), and tetra-triphenylphosphine palladium (57.8 mg, 0.005 mmol) obtained in step (1) were weighed into a Schlenk reaction flask; then, 15 mL of tetrahydrofuran and 3 mL of K2CO3 (concentration 2 mol / L) solution were injected into the reaction flask to form a reaction system; under a nitrogen atmosphere, the reaction system was heated to 70 °C and reacted for 24 h; after the reaction was completed, the mixture was extracted with dichloromethane and saturated NaCl solution, the organic phase was dried with anhydrous Na2SO4, and excess solvent was removed by rotary evaporation to obtain the crude product; the crude product was purified by silica gel column chromatography to obtain a yellow solid, namely intermediate I-b. The NMR data of intermediate I-b are shown in Figure 2, and are as follows: 1 H NMR (500MHz, CDCl3) δ8.18 (d, J=5.9Hz, 4H), 7.55 (s, 2H), 7.52-7.43 (m, 4H), 7.20 (dd, J=8.2, 2.1Hz, 2H), 7 .13 (d, J=2.0Hz, 2H), 7.02 (d, J=8.3Hz, 2H), 6.63 (d, J=6.0Hz, 4H), 4.03 (s, 6H), 3.97 (s, 6H), 3.47 (s, 4H).

[0047] (3) Preparation of catechol-based organic semiconductor material I (WN-OH):

[0048] The synthetic route for this step is as follows:

[0049] Specifically, under a nitrogen atmosphere, intermediate I-b (310.4 mg, 0.5 mmol) obtained in step (2) was weighed into a dry Schlenk reaction flask, and 15 mL of ultra-dry dichloromethane was injected. The temperature was lowered to -20 °C, and after intermediate I-b was completely dissolved, 3 mL of boron tribromide dichloromethane solution (concentration 2 mol / L) was slowly added dropwise. The reaction was carried out at -20 °C for 6 h. After the reaction was completed, water was added to the reaction system to quench the reaction. After separation, the dichloromethane phase was washed three times with deionized water, dried with anhydrous magnesium sulfate, and then excess dichloromethane was removed under reduced pressure. The solid was recrystallized with n-hexane and methanol to obtain a yellow solid, namely WN-OH. The NMR data of WN-OH are shown in Figure 3, and are as follows: 1H NMR (500MHz, d6-DMSO) δ9.12 (s, 4H), 8.48 (d, J=6.6Hz, 4H), 8.32 (s, 2H), 7.47 (s, 4H), 7 .30 (d, J=2.2Hz, 2H), 7.21 (dd, J=13.0, 4.5Hz, 6H), 6.92 (d, J=8.1Hz, 2H), 4.06 (s, 4H).

[0050] Example 2

[0051] (1) Preparation of monolayer MoS2: Monolayer MoS2 was grown using a typical chemical vapor deposition (CVD) method.

[0052] Specifically, this includes: placing MoO3 and S powder, respectively, 2.5 cm (second region) and 26 cm (first region) upstream of a Si / SiO2 substrate in a dual-temperature zone tube furnace; and maintaining an argon flow rate of 100 cm⁻¹. 3 min -1 Under these conditions, the temperature of the Si / SiO2 substrate and the MoO3 placed in the second region is gradually increased to 800℃; when the Si / SiO2 substrate reaches the growth temperature, the S powder placed in the first region is heated to 200℃ to provide S vapor for growing a monolayer of MoS2; after the reaction for 10 min, the furnace is naturally cooled to room temperature, and the sample is sealed in argon gas for further use.

[0053] (2) Fabrication of field-effect transistor (FET) devices: Using a standard wet transfer process, polymethyl methacrylate (PMMA) is used as a support layer to transfer a monolayer of MoS2 grown on a Si / SiO2 substrate to a clean Si / SiO2 substrate.

[0054] Specifically, it includes:

[0055] A layer of PMMA was spin-coated onto a Si / SiO2 substrate on which 1L-MoS2 was grown, and annealed at 100°C for 3 min on a hot plate. The sample was then placed in a 1M KOH solution and immersed at 90°C for 30 min to separate the PMMA film from the original substrate. After washing three times with deionized water, the PMMA / 1L-MoS2 composite film was transferred to the target substrate. After drying on a hot plate at 60°C for 1 h, the sample was immersed in acetone for 1 h to remove the PMMA film.

[0056] For electrode fabrication, AZ5214 photoresist was spin-coated onto a Si substrate and patterned. A 60 nm thick layer of gold (Au) was deposited as the electrode via electron beam evaporation. The Au electrode was precisely aligned and attached to the monolayer MoS2 using a microtransfer device via dry transfer. To achieve functionalization, the FET device based on the monolayer MoS2 was immersed in a 10 mg / mL solution of semiconductor material I in dimethyl sulfoxide (DMSO) and left to stand for 30 min in a light-protected environment. Afterward, it was rinsed with DMSO and acetone sequentially, dried with nitrogen, and finally stored in a desiccator for later use.

[0057] As shown in Figures 4 and 5, Raman spectroscopy (Figure 4) and photoluminescence (PL) spectroscopy (Figure 5) analyses were performed on the WN-OH-treated monolayer MoS2 prepared in Example 1 before and after treatment. In the Raman spectrum (Figure 4), the pristine MoS2... and 404.3cm -1 (A 1g Two active phonon modes are shown at (). A 1g and The wavenumber difference between them is 18.6 cm. -1 less than 20cm -1 This means that MoS2 is a monolayer. Compared to pure MoS2, WN-OH-MoS2 has a higher A 1g The peak showed a red shift, indicating that the WN-OH prepared in Example 1 has an n-type doping effect on monolayer MoS2. In the PL spectrum (Figure 5), compared with pure MoS2, the fluorescence emission peak of WN-OH-MoS2 showed a red shift and a decrease in intensity, which also indicates that the WN-OH prepared in Example 1 has an n-type doping effect on monolayer MoS2.

[0058] As shown in Figure 6, using the Keithley 4200 semiconductor parameter analysis system, under vacuum conditions, the source-drain voltage (V) SD With a gate voltage of 1V and a range of -60V to 60V, the transfer characteristic curves of the FET device were measured. Compared with the MoS2-based FET device, the WN-OH-MoS2-based FET device showed a significant performance improvement, with a current density 7 times that of the MoS2-based device.

[0059] The above description is merely a preferred embodiment of the present invention, and therefore should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent and the contents of the specification should still fall within the scope of the present invention. Industrial applicability

[0060] This invention discloses a catechol-based organic semiconductor material, its preparation method, and its applications. Its structural formula is as follows: Wherein, R is pyridyl. This invention achieves an n-type doping electronic effect on monolayer MoS2. Specifically, the current density of monolayer MoS2 field-effect transistors treated with this invention is increased by more than 6 times compared to the untreated state, making it well-suited for application in field-effect transistors based on two-dimensional materials and possessing industrial applicability.

Claims

1. A catechol-based organic semiconducting material, characterized in that: Its structural formula is Where R is pyridinyl.

2. The method for preparing a catechol-based organic semiconductor material as described in claim 1, characterized in that: Its synthetic route includes the following steps: (1) (2) (3) 3. The preparation method according to claim 2, characterized in that: Includes the following steps: (1) Under a nitrogen atmosphere, 2,7-dibromofluorene and 4-(bromomethyl)pyridine were used as raw materials, tetrabutylammonium bromide was used as a phase transfer catalyst, and 50wt% sodium hydroxide solution and tetrahydrofuran were used as solvents to react to obtain intermediate a; (2) Using intermediate a obtained in step (1) and pinacol 3,4-dimethoxyphenylboronic acid as raw materials, with tetrahydrofuran as solvent, tetra(triphenylphosphine)palladium as catalyst and potassium carbonate as base, the Suzuki reaction was carried out under a protective atmosphere to obtain intermediate b. (3) Dissolve the intermediate b obtained in step (2) in ultra-dry dichloromethane, and add a dichloromethane solution of boron tribromide dropwise under stirring to carry out the reaction. After the reaction is completed, quench the reaction and recrystallize to obtain the catechol-based organic semiconductor material.

4. The preparation method according to claim 3, characterized in that: In step (1), the molar ratio of 2,7-dibromofluorene, 4-(bromomethyl)pyridine, tetrabutylammonium bromide and sodium hydroxide is 1:2.5-3:0.3:10-20, the volume ratio of sodium hydroxide solution to tetrahydrofuran is 2-4:1, the reaction temperature is 35-50℃, and the time is 10-12 h.

5. The preparation method according to claim 3, characterized in that: In step (2), the molar ratio of intermediate a, 3,4-dimethoxyphenylboronic acid pinacol ester, tetrakis(triphenylphosphine)palladium and potassium carbonate is 1:2-2.5:0.05-0.1:3-5, the volume ratio of sodium hydroxide solution to tetrahydrofuran is 2-4:1, the temperature of the Suzuki reaction is 70-80℃, and the time is 10-12h.

6. The preparation method according to claim 3, characterized in that: In step (3), the molar ratio of intermediate b to boron tribromide is 1:8-12, the reaction temperature is -40 to -20℃, and the reaction time is 4-10h.

7. The preparation method according to claim 3, characterized in that: The solvent for the quenching reaction is water or methanol, and the recrystallization specifically involves recrystallizing 3-5 times with n-hexane or methanol.

8. The application of the catechol-based organic semiconductor material as described in claim 1 in the fabrication of field-effect transistors based on two-dimensional materials.

9. A field-effect transistor based on two-dimensional materials, characterized in that: The adsorption on the monolayer MoS2 surface contains fluorene groups with planar aromatic ring structures.

10. The field-effect transistor as claimed in claim 9, characterized in that... The planar aromatic ring fluorene group has the following structural formula: Where R is pyridinyl.

Images