P-type photosensitive field effect transistor material containing a hemithioindigo structure

Abstract

The application relates to a P-type photosensitive field effect transistor material containing a semi-thioindigo structure, and the structural general formula is as follows: wherein R is H, an alkyl group, an alkoxy group, an aryl group or a substituted aryl group. The material has high mobility and strong light response performance, and through corresponding field effect transistor device performance and photosensitive performance research, it is shown that the P-type photosensitive field effect transistor material has good photosensitivity, and provides a material basis for the research and application of sensors.

Description

Technical Field

[0001] The present invention belongs to the technical field of transistor materials, and in particular relates to a P-type photosensitive field effect transistor material containing a semi-thioindigo structure. Background Art

[0002] Organic field-effect transistors (OFETs) are one of the most important organic semiconductor devices, first described in 1986. They use organic semiconductor materials as their conductive channel and offer advantages such as ease of fabrication, lightweight, low cost, good flexibility / elasticity, and good compatibility with flexible substrates. In recent years, research on OFETs has rapidly advanced, attracting widespread attention from both the scientific and industrial communities and becoming a current research hotspot. OFETs can be used in logic gates for ring oscillators in radio frequency cards, active drive circuits for organic flexible displays, organic sensors, memory devices, and electronic paper. They hold great potential for future applications in electronic tags, flexible displays, and sensors. Currently, OFETs are approaching the natural limits of miniaturization and are relatively expensive, with numerous challenges in fabricating large-surface devices. Furthermore, with the continuous improvement of people's lifestyles, flexible, foldable, and wearable electronic products are becoming a major future development direction, with low-cost processing becoming a key competitive advantage. This is a huge challenge for microelectronics based on inorganic semiconductors. Exploring the use of organic semiconductors as active materials for field-effect transistors is an inevitable trend with important research value and prospects. However, research on field-effect transistor materials with photosensitivity is insufficient.

[0003] Benzothiophene [3,2-b]benzothiophene (BTBT) is a classic semiconductor core material used in organic field-effect transistors (OFETs). This material exhibits high carrier mobility in OFETs. However, the photoresponse performance of this single material is poor.

[0004] Thioindigo / hemithioindigo are dye molecules that have long been widely used in the pigment industry. Can traditional commercial material structures be applied to the emerging semiconductor industry? Hemithioindigo molecules undergo luminescent isomerization under light irradiation. The carbon-carbon double bond in the hemithioindigo structure can undergo Z- and E-type transitions under different light conditions. (See Bull. Chem. Soc. Jpn, 1992, 65, 649-656, Bull. Chem. Soc. Jpn, 1992, 65, 657-663, Chemical Physics Letters 428 (2006) 167–173.) The following configurational transitions are shown:

[0005]

[0006] However, there are currently no reports on combining the high mobility of BTBT with the property of hemithioindigo molecules that can undergo conformational transitions under specific light conditions to synthesize semiconductor materials with high mobility and strong light response properties. Summary of the Invention

[0007] In response to the above-mentioned situation of the prior art, the present invention proposes a P-type photosensitive field-effect transistor material containing a semi-thioindigo structure. By combining the high mobility of BTBT with the property that semi-thioindigo molecules can undergo configurational transformation under specific light conditions, the P-type photosensitive field-effect transistor material containing a semi-thioindigo structure proposed in the present invention has high mobility and strong light response performance.

[0008] According to the present invention, a P-type photosensitive field effect transistor material containing a semi-thioindigo structure is provided, and its general structural formula is as follows:

[0009]

[0010] Wherein, R can be H, alkyl, alkoxy, aryl or substituted aryl.

[0011] Furthermore, R is preferably H.

[0012] Furthermore, R is preferably C1 to C 20 Alkyl, more preferably C6 to C 12 (i.e., an alkyl group having 6 to 12 carbon atoms).

[0013] Furthermore, the structural formula of R is preferably an alkoxy chain having 1 to 20 carbon atoms, and more preferably an alkoxy chain having 4 to 10 carbon atoms.

[0014] Furthermore, R is preferably a phenyl group.

[0015] Furthermore, R is preferably an alkyl-substituted phenyl group, with the structural formula The length of the alkyl chain is 1 to 20 carbon atoms, more preferably 4 to 10 carbon atoms.

[0016] Furthermore, R is preferably an alkoxy-substituted phenyl group, with the structural formula The length of the alkoxy chain is such that the number of carbon atoms n is 1 to 20, more preferably 1 to 10.

[0017] By combining the high mobility of BTBT with the property of hemithioindigo molecules that can undergo configurational transformation under specific light conditions, the present invention designs and synthesizes a P-type photosensitive field-effect transistor material containing a hemithioindigo structure. The material has high mobility and strong light response performance. Corresponding field-effect transistor device performance and photosensitivity studies show that the P-type photosensitive field-effect transistor material of the present invention has excellent photosensitivity, providing a material basis for the research and application of sensors. DETAILED DESCRIPTION

[0018] In order to more clearly understand the purpose, technical solutions and advantages of the present invention, the present invention is further described in detail below with reference to the embodiments.

[0019] The present invention combines the high mobility of BTBT with the property that hemithioindigo molecules can undergo configurational transformation under specific light conditions to propose a P-type photosensitive field-effect transistor material containing a hemithioindigo structure. The P-type photosensitive field-effect transistor material containing a hemithioindigo structure proposed in the present invention has high mobility and strong light response performance.

[0020] The general synthesis formula of the material of the present invention is as follows:

[0021]

[0022] Step 1: 1-Benzothiophene-3(2H)-one (I in the above general synthetic formula) is dissolved in benzene, and an equivalent amount of p-bromobenzaldehyde (II in the above general synthetic formula) and a catalytic amount of piperidine are added. The reaction is heated to reflux and monitored by thin-layer chromatography until completion. Saturated aqueous ammonium chloride is added, and the mixture is extracted three times with ethyl acetate. The organic phases are combined and dried to obtain the intermediate bromohemithioindigo (III in the above general synthetic formula);

[0023] Step 2: Using the brominated hemithioindigo (III) obtained in step 1 under palladium catalyst conditions to prepare the corresponding hemithioindigopinacol borate (IV in the above synthetic formula);

[0024] Step 3: The target compound (T in the above synthetic formula) can be obtained by Suzuki coupling reaction of the hemithioindigopinacol borate (IV) obtained in step 2 with a unilateral bromine-substituted BTBT derivative (V in the above synthetic formula).

[0025] Example 1: Synthesis of Representative Compound T-1

[0026] The synthetic route of compound T-1 is as follows:

[0027]

[0028] 15 g (0.1 mol) of 1-benzothiophene-3(2H)-one (I) was dissolved in 200 mL of benzene, and 18.5 g (0.1 mol) of p-bromobenzaldehyde (II) and 0.5 g of piperidine were added. The mixture was heated under reflux for 3 h. The reaction was monitored for completion by thin-layer chromatography. 200 mL of saturated aqueous ammonium chloride was added, and the mixture was extracted three times with ethyl acetate. The organic phases were combined and dried to yield 28.4 g of the intermediate bromohemithioindigo (III). 1HNMR (500MHz, CDCl3) δ8.35 (s, 1H), 8.02–7.86 (m, 6H), 7.79 (dd, J = 15.3, 3.0Hz, 1H), 7.61 (td, J = 14.9, 3.2Hz, 1H).

[0029] 15.85 g (0.05 mol) of bromohemithioindigo (III), 15.2 g (0.06 mol) of pinacol diboronate, and 5.88 g (0.06 mol) of potassium acetate were dissolved in 200 mL of dimethyl sulfoxide, and 1% mol equivalent of [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium dichloromethane complex was added under a nitrogen atmosphere. The reaction was stirred at 90 ° C overnight under a nitrogen atmosphere. After the reaction was completed, it was cooled to room temperature, 50 mL of water was added, and the mixture was extracted three times with dichloromethane. The organic phases were combined, washed with water, dried over anhydrous sodium sulfate, concentrated, and separated by column chromatography using dichloromethane / petroleum ether as eluent to obtain 15.6 g of compound hemithioindigopinacol borate (IV).

[0030] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 6.4 g (0.02 mol) of 2-bromoBTBT (V-1) were dissolved in 50 mL of toluene. 10 mL of a 2 mol / L aqueous potassium carbonate solution was added, and the mixture was purged with nitrogen for 30 minutes. A 2% equivalent of Pd(PPh3)4 was added, and the mixture was heated under reflux and stirred for 12 hours under a nitrogen atmosphere. After the reaction, the mixture was added to 100 mL of methanol solution to precipitate a solid, which was recrystallized from dichloromethane and n-hexane to obtain 5.4 g of the target compound T-1.

[0031] 1 H NMR (500MHz, Chloroform) δ8.35 (s, 1H), 8.21–8.12 (m, 2H), 8.01–7.90 (m, 3H), 7.89–7.69 (m, 7H), 7.61 (td, J = 14.9, 3.2Hz, 1H), 7.38–7.25 (m, 2H).

[0032] Example 2: Synthesis of Representative Compound T-2

[0033] The synthetic route of compound T-2 is as follows:

[0034]

[0035] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 8.0 g (0.02 mol) of bromoBTBT derivative (V-2) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid. The solid was recrystallized from dichloromethane and n-hexane to obtain 7.43 g of the target compound T-2.

[0036] 1 H NMR(500MHz,Chloroform)δ8.34(s,1H),8.23–8.10(m,2H),8.01–7.88(m,3H),7.84–7.69(m,7H),7.60(td,J=14.9,3.2 Hz,1H),7.31(dd,J=15.0,2.9Hz,1H),2.64(t,J=15.7Hz,2H),1.71–1.50(m,2H),1.41–1.19(m,6H),1.03–0.78(m,3H).

[0037] Example 3: Synthesis of Representative Compound T-3

[0038] The synthetic route of compound T-3 is as follows:

[0039]

[0040] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 8.54 g (0.02 mol) of bromoBTBT derivative (V-3) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid. The solid was recrystallized from dichloromethane and n-hexane to obtain 5.4 g of the target compound T-3.

[0041] 1H NMR(500MHz,Chloroform)δ8.35(s,1H),8.23–8.11(m,2H),8.01–7.88(m,3H),7.85–7.69(m,7H),7.61(td,J=14.9,3.2 Hz,1H),7.32(dd,J=14.9,3.0Hz,1H),2.64(t,J=15.7Hz,2H),1.77–1.42(m,2H),1.40–1.06(m,9H),1.00–0.72(m,3H).

[0042] Example 4: Synthesis of Representative Compound T-4

[0043] The synthetic route of compound T-4 is as follows:

[0044]

[0045] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 9.7 g (0.02 mol) of bromoBTBT derivative (V-4) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid, which was recrystallized from dichloromethane and n-hexane to obtain 8.5 g of the target compound T-4.

[0046] 1 H NMR(500MHz,Chloroform)δ8.35(s,1H),8.21–8.13(m,2H),8.01–7.88(m,3H),7.84–7.70(m,7H),7.61(td,J=14.9,3.2 Hz,1H),7.32(dd,J=15.0,3.1Hz,1H),2.64(t,J=15.7Hz,2H),1.82–1.46(m,2H),1.38–1.12(m,18H),1.03–0.70(m,3H).

[0047] Example 5: Synthesis of Representative Compound T-5

[0048] The synthetic route of compound T-5 is as follows:

[0049]

[0050] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 7.9 g (0.02 mol) of bromoBTBT derivative (V-5) were dissolved in 50 mL of toluene, 10 mL of 2 mol / L potassium carbonate aqueous solution was added, and nitrogen was blown for 30 min. 2% equivalent of Pd(PPh3)4 was added, and the mixture was heated under reflux with stirring for 12 h under a nitrogen environment. After the reaction, the mixture was added to 100 mL of methanol solution to precipitate a solid, which was recrystallized from dichloromethane and n-hexane to obtain 9.2 g of the target compound T-5.

[0051] 1 H NMR (500MHz, Chloroform) δ8.35 (s, 1H), 8.23–8.11 (m, 4H), 8.03–7.89 (m, 4H), 7.84–7.70 (m, 7H), 7.61 (td, J = 14.9, 3.2Hz, 1H), 7.54–7.33 (m, 3H).

[0052] Example 6: Synthesis of Representative Compound T-6

[0053] The synthetic route of compound T-6 is as follows:

[0054]

[0055] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 9.0 g (0.02 mol) of bromoBTBT derivative (V-6) were dissolved in 50 mL of toluene. 10 mL of a 2 mol / L aqueous potassium carbonate solution was added, and the mixture was purged with nitrogen for 30 minutes. A 2% equivalent of Pd(PPh3)4 was added, and the mixture was heated under reflux and stirred for 12 hours under a nitrogen atmosphere. After the reaction, the mixture was added to 100 mL of methanol solution to precipitate a solid, which was recrystallized from dichloromethane and n-hexane to obtain 8.2 g of the target compound T-6.

[0056] 1 H NMR(500MHz,Chloroform)δ8.35(s,1H),8.22–8.11(m,4H),8.05–7.87(m,4H),7.85–7.68(m,5H),7.67–7.55(m ,3H),7.33–7.21(m,2H),2.65(t,J=15.7Hz,2H),1.70–1.47(m,2H),1.45–1.16(m,2H),0.89(t,J=13.0Hz,3H).

[0057] Example 7: Synthesis of Representative Compound T-7

[0058] The synthetic route of compound T-7 is as follows:

[0059]

[0060] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 9.8 g (0.02 mol) of bromoBTBT derivative (V-7) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid, which was recrystallized from dichloromethane and n-hexane to obtain 9.6 g of the target compound T-7.

[0061] 1 H NMR(500MHz,Chloroform)δ8.35(s,1H),8.21–8.13(m,4H),8.00–7.89(m,4H),7.84–7.70(m,5H),7.66–7.56(m,3 H),7.32–7.22(m,2H),2.63(t,J=15.7Hz,2H),1.63(qd,J=15.7,7.8Hz,2H),1.38–1.15(m,8H),1.00–0.75(m,3H).

[0062] Example 8: Synthesis of Representative Compound T-8

[0063] The synthetic route of compound T-8 is as follows:

[0064]

[0065] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 10.7 g (0.02 mol) of bromoBTBT derivative (V-8) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux with stirring for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid, which was recrystallized from dichloromethane and n-hexane to obtain 6.8 g of the target compound T-8.

[0066] 1H NMR(500MHz,Chloroform)δ8.35(s,1H),8.22–8.10(m,4H),8.03–7.88(m,4H),7.84–7.69(m,5H),7.67–7.54 (m,3H),7.39–7.21(m,2H),2.63(t,J=15.7Hz,2H),1.82–1.49(m,2H),1.41–1.14(m,15H),0.99–0.75(m,3H).

[0067] Example 9: Synthesis of Representative Compound T-9

[0068] The synthetic route of compound T-9 is as follows:

[0069]

[0070] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 8.5 g (0.02 mol) of bromoBTBT derivative (V-9) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction, the mixture was added to 100 mL of methanol solution to precipitate a solid. The solid was recrystallized from dichloromethane and n-hexane to obtain 7.6 g of the target compound T-9.

[0071] 1 H NMR (500MHz, Chloroform) δ8.35(s,1H),8.23–8.07(m,4H),8.01–7.89(m,4H),7.84–7.69(m,5H),7.65–7.54(m,3H),7.03–6.91(m,2H),3.79(s,3H).

[0072] Example 10: Synthesis of Representative Compound T-10

[0073] The synthetic route of compound T-10 is as follows:

[0074]

[0075] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 9.6 g (0.02 mol) of bromoBTBT derivative (V-10) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid, which was recrystallized from dichloromethane and n-hexane to obtain 7.9 g of the target compound T-10.

[0076] 1 H NMR(500MHz,Chloroform)δ8.35(s,1H),8.23–8.12(m,4H),8.01–7.88(m,4H),7.83–7.70(m,5H),7.66–7.54 (m,3H),7.04–6.92(m,2H),4.11(t,J=14.7Hz,2H),1.91–1.60(m,2H),1.51–1.19(m,4H),1.03–0.70(m,3H).

[0077] Example 11: Synthesis of Representative Compound T-11

[0078] The synthetic route of compound T-11 is as follows:

[0079]

[0080] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 10.5 g (0.02 mol) of bromoBTBT derivative (V-11) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid. The solid was recrystallized from dichloromethane and n-hexane to obtain 8.5 g of the target compound T-11.

[0081] 1 H NMR(500MHz,Chloroform)δ8.35(s,1H),8.22–8.10(m,4H),8.02–7.86(m,4H),7.84–7.69(m,5H),7.67–7.52(m,3H) ),7.07–6.91(m,2H),4.11(t,J=14.9Hz,2H),1.74(pd,J=14.8,1.0Hz,2H),1.51–1.16(m,10H),0.95–0.82(m,3H).

[0082] Example 12: Synthesis of Representative Compound T-12

[0083] The synthetic route of compound T-12 is as follows:

[0084]

[0085] 7.2 g (0.02 mmol) of hemithioindigopinacol borate (IV) and 11.0 g (0.02 mol) of bromoBTBT derivative (V-12) were dissolved in 50 mL of toluene, and 10 mL of 2 mol / L potassium carbonate aqueous solution was added. The mixture was purged with nitrogen for 30 min, and 2% equivalent of Pd(PPh3)4 was added. The mixture was heated under reflux and stirred for 12 h under a nitrogen environment. After the reaction was completed, the mixture was added to 100 mL of methanol solution to precipitate a solid. The solid was recrystallized from dichloromethane and n-hexane to obtain 7.5 g of the target compound T-12.

[0086] 1 H NMR(500MHz,Chloroform)δ8.35(s,1H),8.21–8.12(m,4H),8.00–7.88(m,4H),7.84–7.70(m,5H),7.66–7.54(m,3H) ),7.03–6.93(m,2H),4.11(t,J=14.8Hz,2H),1.74(qd,J=15.8,1.3Hz,2H),1.52–1.19(m,15H),0.99–0.80(m,3H).

[0087] Preparation of organic field-effect transistors

[0088] Silicon wafer cleaning and modification

[0089] The Si / SiO2 substrate was purchased directly from the market, with a SiO2 thickness of 250 nm. The silicon wafer was ultrasonically cleaned with purified water, acetone, and isopropanol for 10 min, respectively. After drying with nitrogen, it was irradiated with UV light for 10 min. A clean silicon wafer was obtained. The wafer was then immersed in a 0.1 mol / L OTS(8) toluene solution at 65°C for 20 min. Surface residues were then removed by washing with toluene and dried with nitrogen to obtain an OTS-modified silicon wafer for later use.

[0090] Device preparation and performance testing

[0091] Use semiconductor mask to mask the silicon wafer and select appropriate substrate temperature. Prepare the thin film under high vacuum. The vacuum degree is about 2.0×10 -4 Pa, the semiconductor material (the semiconductor material obtained according to the above embodiments 1-12 of the present invention) evaporation rate is controlled at After the film is prepared, the electrode mask is used for electrode evaporation. The electrode material is Au. The Au electrode evaporation rate is controlled at The device channel width-to-length ratios fabricated were 380μm / 38μm, 580μm / 58μm, 780μm / 78μm, and 980μm / 98μm. Semiconductor performance was tested using a Keithly 4200 semiconductor analyzer. Id-Vg and Id-Vd curves were measured under normal conditions and under UV illumination. Mobility was calculated using the following formula.

[0092] I d =(W / 2L)μ TFT C i (V g -V th ) 2

[0093] The switching ratio of the device is obtained based on the current ratio at 0V and -60V.

[0094] The device performance of the representative semiconductor materials obtained according to the above embodiments 1-12 of the present invention is as follows:

[0095] Device data of compound DPh-BTBF:

[0096]

[0097]

[0098] According to the above table, it can be seen from the mobility data under normal conditions and light radiation that the representative semiconductor materials obtained according to the above Examples 1-12 of the present invention show good photosensitivity.

Claims

1. A P-type photosensitive field effect transistor material containing a semi-thioindigo structure, the general structure of which is as follows: in, R is H, alkyl, alkoxy, aryl or substituted aryl.

2. The P-type photosensitive field effect transistor material containing a hemithioindigo structure according to claim 1, wherein R is H.

3. The P-type photosensitive field effect transistor material containing a hemithioindigo structure according to claim 1, wherein R is an alkyl group with 1 to 20 carbon atoms.

4. The P-type photosensitive field effect transistor material containing a hemithioindigo structure according to claim 1, wherein R is an alkoxy chain having 1 to 20 carbon atoms.

5. The P-type photosensitive field effect transistor material containing a hemithioindigo structure according to claim 1, wherein R is a phenyl group.

6. The P-type photosensitive field effect transistor material containing a hemithioindigo structure according to claim 1, wherein R is an alkyl-substituted phenyl group, and the structural formula is , wherein the length of the alkyl chain is 1 to 20 carbon atoms.

7. The P-type photosensitive field effect transistor material containing a hemithioindigo structure according to claim 1, wherein R is an alkoxy-substituted phenyl group, and the structural formula is , wherein the length of the alkoxy chain is 1 to 20 carbon atoms.

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