Bis-carbazole compound and preparation method and co-sensitization application thereof

Abstract

The preparation method specifically comprises the following steps: dissolving a compound shown as a formula II-1, a formula II-2, a formula II-3, a formula II-4 or a formula II-5 and cyanoacetic acid in a solvent, adding an alkaline substance, carrying out a heating reflux reaction under stirring, and after the reaction is finished, concentrating the reaction liquid to remove the solvent, thereby obtaining the dicarbazole compound shown as the formula II-1, the formula II-2, the formula II-3, the formula II-4 or the formula II-5. Dissolving the obtained concentrate in an eluent, carrying out separation and purification through column chromatography silica gel, collecting the eluent, and evaporating to remove the eluent to obtain a target product, such as a compound of a formula DSB-1, a formula DSB-2, a formula DSB-3, a formula DSB-4 or a formula DSB-5, and using the target product to prepare a dye sensitizer # imgabs0 #. The dicarbazole compound is synthesized by using carbazole as a raw material and introducing a benzothiadiazole receptor and an aromatic heterocyclic ring into one carbazole, introducing a benzene ring as a bridged bond and cyanoacetic acid as a receptor into the other carbazole, so that a new applicable substance is added for screening dye sensitizers.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical organic synthesis, and in particular relates to a biscarbazole compound and a preparation method and co-sensitization application thereof. Background Art

[0002] DSSCs (dye-sensitized solar cells) are expected to replace traditional solar cells due to their low production cost, low environmental pollution and high photoelectric conversion efficiency. As one of the main components of DSSCs, dye sensitizers play an important role in absorbing light. Their flexible molecular design has always been the focus of research on improving battery performance. Traditional D-π-A structured dye sensitizers are limited by electron donors, conjugated bridges and electron acceptors, and their light absorption performance is still not ideal. In order to broaden the absorption spectrum, many new structures such as DA′-π-A, DD′-π-A, A′-π-D-π′-A, etc. have been reported. This method of introducing additional electron donors, electron acceptors and increasing the conjugated system can often effectively adjust the light absorption ability of dye molecules. Summary of the invention

[0003] In view of the above technical problems existing in the prior art, the purpose of the present invention is to provide a biscarbazole compound and a preparation method and application thereof. The biscarbazole compound can be co-sensitized with the metal dye sensitizer Z907. The assembled dye-sensitized solar cell has good photoelectric conversion efficiency, which adds new applicable substances to the screening of dye sensitizer Z907 co-sensitizer.

[0004] The present invention provides a class of biscarbazole compounds, whose molecular structures are shown in Formula DSB-1, Formula DSB-2, Formula DSB-3, Formula DSB-4 or Formula DSB-5;

[0005]

[0006] The present invention also provides a method for preparing a biscarbazole compound, comprising the following steps: dissolving a compound represented by formula II-1, formula II-2, formula II-3, formula II-4 or formula II-5 and cyanoacetic acid in a solvent, adding an alkaline substance, heating under stirring and reflux reaction, after the reaction is completed, concentrating the reaction solution to remove the solvent, dissolving the obtained concentrate in an eluent, separating and purifying it through column chromatography silica gel, collecting the eluent and evaporating the eluent to obtain a target product such as a compound represented by formula DSB-1, formula DSB-2, formula DSB-3, formula DSB-4 or formula DSB-5;

[0007] The structural formula of the compound represented by formula II-1, formula II-2, formula II-3, formula II-4 or formula II-5 is as follows:

[0008]

[0009] Furthermore, the heating reflux reaction time is 6-10h.

[0010] Furthermore, the solvent is a mixed solution of at least two of chloroform, toluene and acetonitrile, preferably a mixed solution of toluene and acetonitrile.

[0011] Furthermore, the molar ratio of the compound represented by formula II-1, formula II-2, formula II-3, formula II-4 or formula II-5, cyanoacetic acid and the alkaline substance is 1:1.2 to 5:12 to 61, preferably 1:2:20.

[0012] Furthermore, the alkaline substance is piperidine.

[0013] Furthermore, the ratio of the amount of the compound represented by Formula II-1, Formula II-2, Formula II-3, Formula II-4 or Formula II-5 to the volume of the solvent is 1:20-50, the unit of the amount of the substance is mmol, and the unit of volume is mL.

[0014] Furthermore, the eluent is a mixed solvent consisting of dichloromethane and methanol, and the volume ratio of dichloromethane to methanol is 12:1.

[0015] Furthermore, the synthesis method of the compound represented by formula (II-1), formula (II-2), formula (II-3), formula (II-4) or formula (II-5) is as follows:

[0016] A compound represented by formula (IVa), formula (IVb), formula (IVc), formula (IVd) or formula (IVe), a compound represented by formula (III), tetrakistriphenylphosphine palladium and potassium carbonate are dissolved in a mixed solvent of tetrahydrofuran and water, heated to reflux for reaction, and after the reaction is completed, the reaction solution is cooled to room temperature and poured into water. The reaction solution is extracted with dichloromethane and dried, and the solvent is removed by rotary evaporation and then separated and purified by column chromatography to obtain a product represented by formula (II-1), formula (II-2), formula (II-3), formula (II-4) or formula (II-5).

[0017]

[0018] Furthermore, the column chromatography separation process: the concentrate is dissolved in the eluent and then separated and purified by column chromatography silica gel, the eluent is collected and the eluent is evaporated, and then dried to obtain a solid powder product; when synthesizing the compound represented by formula (II-1), formula (II-2) or formula (II-3), the eluent is petroleum ether and dichloromethane in a volume ratio of 1:2; the eluent of formula (II-4) or formula (II-5) is dichloromethane and methanol in a volume ratio of 20:1.

[0019] Furthermore, the present invention also provides the use of biscarbazole compounds in dye sensitizers.

[0020] By adopting the above technology, compared with the prior art, the present invention has the following beneficial effects: the present invention connects the bicarbazole with an alkyl chain, introduces a benzothiadiazole receptor and an aromatic heterocycle into one carbazole, introduces a benzene ring as a bridge bond into the other carbazole, and uses cyanoacetic acid as an receptor to synthesize a bicarbazole compound, which can be used as a co-sensitizer of Z907. The dye-sensitized solar cell co-sensitized by the compound and Z907 has a good photoelectric conversion efficiency, which adds a new applicable substance to the screening of dye sensitizers. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0022] Example 1 Synthesis of the compound represented by formula (DSB-1):

[0023]

[0024] 1) Synthesis of the compound represented by formula (III)

[0025] Compound V (0.51 g, 1.36 mmol), compound VI (0.60 g, 1.50 mmol) and cesium carbonate (0.88 g, 2.72 mmol) were added to the reaction flask, and solvent DMF (20 ml) was added, and the mixture was heated to reflux and reacted for 6 h. After the reaction was completed, the reaction solution was put into a large amount of water and extracted with dichloromethane. The extraction was repeated three times, and the organic layers were combined. The mixture was then washed with saturated NaCl solution, the solvent was removed by rotary evaporation, and the mixture was purified by column chromatography (V PE :V EA =5:1) to give an orange solid III (0.68 g, 70.1%).

[0026] The compound represented by formula III: melting point: 210-215°C. 1 H NMR (400 MHz, CDCl 3)δ10.08(d,J=4.3Hz,1H),8.63(d,J=1.5Hz,1H),8.37(t,J=1.6Hz,1H),8.18(t,J=6 .8Hz,2H),8.03-7.94(m,4H),7.87(d,J=8.2Hz,2H),7.71(dd,J=8.5,1.8Hz,1H),7.6 5(d,J=7.6,2.2Hz,1H),7.53-7.46(m,2H),7.41(dd,J=8.4Hz,1H),7.35(t,J=4.1Hz ,2H),7.32(d,J=5.1Hz,1H),7.29(d,J=5.6Hz,2H),4.31-4.29(m,4H),2.04(bs,4H).

[0027] 2) Synthesis of the compound represented by formula (II-1)

[0028] Compound III (0.20 g, 0.28 mmol), phenylboronic acid IVa (0.07 g, 0.56 mmol), Pd(PPh 3 ) 4 (0.02g) and K 2 CO 3 (0.15 g, 1.12 mmol), THF (5 ml) and H 2 O (1 ml), heated to reflux, reacted for 6 hours. After the reaction was completed, the reaction solution was put into a large amount of water, extracted with dichloromethane, repeated three times, and the organic layers were combined. Then washed with saturated NaCl solution, the solvent was removed by rotary evaporation, and the resultant was analyzed by column chromatography (V PE :V DCM =1:2) to obtain an orange solid II-1 (0.16 g, 83.4%).

[0029] Compound represented by formula II-1: melting point: 205-210°C. 1 H NMR (400 MHz, CDCl 3)δ10.08(s,1H),8.71(d,J=1.5Hz,1H),8.39(d,J=1.6Hz,1H),8.21(d,J=7.7Hz,1H),8.18(d,J=7.7Hz ,1H),8.10(dd,J=8.5,1.6Hz,1H),8.04-8.00(m,2H),7.98(d,J=8.3Hz,2H),7.89(dd,J=7.7,5.5Hz,3 H),7.84(d,J=7.3Hz,1H),7.73(dd,J=8.5,1.7Hz,1H),7.60(t,J=7.6Hz,2H),7.53-7.48(m,3H),7.45 (d,J=8.5Hz,1H),7.38-7.35(m,3H),7.31(d,J=7.1Hz,2H),4.39-4.25(m,4H),2.07(d,J=7.7Hz,4H).

[0030] 3) Synthesis of the compound represented by formula (DSB-1)

[0031] Weigh compound II-1 (0.12 g, 0.17 mmol) and cyanoacetic acid (0.03 g, 0.34 mmol) into a reaction flask, add toluene (1 ml) and acetonitrile (3 ml) as solvents, then slowly drop piperidine (0.2 ml), heat under reflux, and react for 10 h. After the reaction is completed, put the reaction solution into a large amount of water, extract with dichloromethane, repeat three times, and combine the organic layers. Then wash with saturated NaCl solution, remove the solvent by rotary evaporation, and analyze by column chromatography (V DCM :V MeOH =12:1) to obtain orange solid DSB-1 (0.05 g, 37.5%).

[0032] Compound represented by formula (DSB-1): melting point: 243-249°C. 1H NMR (400MHz, DMSO) δ13.43(s,1H),8.81(s,1H),8.67(s,1H),8.37(s,1H),8.27(d,J=7.8Hz,1H),8 .24(d,J=7.7Hz,1H),8.16(d,J=8.5Hz,2H),8.10(dd,J=8.6,1.6Hz,1H),8.06-8.00(m,5H),7.98(d ,J=7.4Hz,1H),7.88(d,J=8.6Hz,1H),7.68(dd,J=8.6,3.3Hz,2H),7.63(d,J=8.3Hz,2H),7.59(d, J=7.6Hz,2H),7.51-7.45(m,3H),7.24(t,J=7.4Hz,2H),4.46(bs,4H),1.92(bs,4H).HRMS(ESI)m / z calcd for C 50 H 35 N 5 O 2 SNa + [M+Na] + 792.2409, found 792.2408.

[0033] Example 2 Synthesis of the compound represented by formula (DSB-2):

[0034]

[0035] 1) Synthesis of the compound represented by formula (II-2)

[0036] Compound III (0.20 g, 0.28 mmol), 2-thiopheneboronic acid IVb (0.07 g, 0.55 mmol), Pd(PPh 3 ) 4 (0.02g) and K 2 CO 3 (0.16 g, 1.12 mmol), then THF (5 ml) and H 2 O (1 ml), heated to reflux, reacted for 6 hours. After the reaction was completed, the reaction solution was put into a large amount of water, extracted with dichloromethane, repeated three times, and the organic layers were combined. Then washed with saturated NaCl solution, the solvent was removed by rotary evaporation, and the reaction mixture was purified by column chromatography (V PE :V DCM =1:2) to obtain an orange solid II-2 (0.12 g, 62%).

[0037] Compound represented by formula (II-2): melting point: 236-240°C. 1H NMR (400 MHz, CDCl 3 )δ10.07(s,1H),8.70(d,J=1.5Hz,1H),8.37(dd,J=1.6Hz,1H),8.24-8.15(m,3H) ,8.07(dd,J=8.5,1.7Hz,1H),8.02-7.94(m,3H),7.87(d,J=8.2Hz,2H),7.82(d,J= 7.4Hz,1H),7.74-7.69(m,1H),7.54-7.47(m,3H),7.42(d,J=8.5Hz,1H),7.39-7. 33(m,3H),7.33-7.29(m,2H),7.27-7.25(m,1H),4.52-4.15(m,4H),2.05(bs,4H).

[0038] 2) Synthesis of the compound represented by formula (DSB-2)

[0039] Weigh II-2 (0.12 g, 0.17 mmol) and cyanoacetic acid (0.02 g, 0.22 mmol) into a reaction flask, add toluene (1 ml) and acetonitrile (3 ml) as solvents, slowly drop piperidine (0.2 ml), heat under reflux, and react for 10 h. After the reaction is completed, put the reaction solution into a large amount of water, extract with dichloromethane, repeat three times, and combine the organic layers. Then wash with saturated NaCl solution, remove the solvent by rotary evaporation, and analyze by column chromatography (V DCM :V MeOH =12:1) to obtain orange-yellow solid DSB-2 (0.072 g, 55%).

[0040] Compound represented by formula (DSB-2): melting point: 210-215°C. 1 H NMR (400MHz, DMSO) δ8.79(s,1H),8.65(s,1H),8.36(s,1H),8.26(d,J=7.6Hz,1H),8.22( d,J=7.9Hz,1H),8.19-8.11(m,4H),8.06(d,J=8.6Hz,1H),8.00(d,J=8.4Hz,2H),7.95(d J=7.5Hz,1H),7.85(t,J=8.6Hz,1H),7.75(d,J=4.3Hz,1H),7.67-7.58(m,4H),7.46(t,J=7.6 Hz,2H),7.29-7.27(m,1H),7.23(t,J=7.3Hz,2H),4.43(bs,4H),1.90(bs,4H).HRMS(ESI)m / z calcd forC 48 H33 N 5 O 2 S 2 Na + [M+Na] + 798.1973, found 798.1979.

[0041] Example 3 Synthesis of the compound represented by formula (DSB-3):

[0042]

[0043] 1) Synthesis of the compound represented by formula (II-3)

[0044] Compound III (0.20 g, 0.28 mmol), 2-furanboronic acid IVc (0.063 g, 0.56 mmol), Pd(PPh 3 ) 4 (20 mg) and K 2 CO 3 (160 mg, 1.12 mmol), then THF (5 ml) and H 2 O (1 ml), heated to reflux, reacted for 6 hours. After the reaction was completed, the reaction solution was put into a large amount of water, extracted with dichloromethane, repeated three times, and the organic layers were combined. Then washed with saturated NaCl solution, the solvent was removed by rotary evaporation, and the resultant was analyzed by column chromatography (V PE :V DCM =1:2) to obtain an orange solid II-3 (0.11 g, 59%).

[0045] Compound represented by formula (II-3): melting point: 245-247°C. 1 H NMR (400 MHz, CDCl 3 )δ10.09(s,1H),8.63(d,J=1.5Hz,1H),8.38(d,J=1.6Hz,1H),8.24-8.13 (m,3H),8.01-7.95(m,5H),7.87(d,J=8.2Hz,2H),7.72(dd,J=8.5,1.8Hz ,1H),7.67(d,J=7.6Hz,1H),7.53-7.46(m,3H),7.40(d,J=8.4Hz,1H),7. 37-7.34(m,3H),7.31(d,J=7.4Hz,2H),4.31-4.30(m,4H),2.05(bs,4H).

[0046] 2) Synthesis of the compound represented by formula (DSB-3)

[0047] Weigh compound II-3 (0.11 g, 0.16 mmol) and cyanoacetic acid (0.02 g, 0.22 mmol) into a reaction bottle, add solvent toluene (1 ml) and acetonitrile (3 ml), then slowly drop piperidine (0.2 ml), heat under reflux, and react for 10 hours. After the reaction is completed, put the reaction solution into a large amount of water, extract with dichloromethane, repeat three times, and combine the organic layers. Then wash with saturated NaCl solution, remove the solvent by rotary evaporation, and analyze by column chromatography (V DCM :V MeOH =12:1) to obtain orange solid compound DSB-3 (0.11 g, 88%).

[0048] Compound represented by formula (DSB-3): melting point: 213-217°C. 1 H NMR (400MHz, DMSO) δ8.74(s,1H),8.59(s,1H),8.24(d,J=7.6Hz,1H),8.20(d,J= 7.8Hz,1H),8.16-8.07(m,2H),8.05-8.00(m,3H),7.92(d,J=8.3Hz,2H),7.85-7. 79(m,2H),7.72(d,J=7.0Hz,1H),7.66(d,J=8.7Hz,1H),7.61-7.56(m,4H),7.47 -7.40(m,3H),7.24-7.17(m,2H),4.43-4.41(m,4H),1.89(bs,4H).HRMS(ESI)m / z calcd for C 48 H 33 N 5 O 3 SNa + [M+Na] + 782.2202, found 782.2195.

[0049] Example 4 Synthesis of the compound represented by formula (DSB-4):

[0050]

[0051] 1) Synthesis of the compound represented by formula (II-4)

[0052] Compound III (140 mg, 0.2 mmol), pyridine-4-boronic acid IVd (40 mg, 0.33 mmol), Pd(PPh 3 ) 4(7mg) and potassium carbonate (135mg), vacuum nitrogen exchange three times, then add saturated potassium carbonate (41mg, 0.3mmol, 2M) aqueous solution and THF (6ml) as solvent, under nitrogen protection, heat reflux, react for 6h. After the reaction is completed, the reaction solution is put into a large amount of water, extracted with dichloromethane, repeated three times, and the organic layers are combined. Then wash with saturated NaCl solution, remove the solvent by rotary evaporation, and analyze by column chromatography (V DCM :V MeOH =20:1) to obtain an orange solid II-4 (80 mg, 57%).

[0053] Compound represented by formula (II-4): melting point: 245-247°C. 1 H NMR (400 MHz, CDCl 3 )δ10.08(s,1H),8.82(d,J=6.0Hz,2H),8.73(d,J=1.5Hz,1H),8.38(d,J=1.5Hz,1H),8.21(d,J=7. 7Hz,1H),8.18(d,J=7.7Hz,1H),8.09(dd,J=8.5,1.7Hz,1H),8.05(d,J=6.1Hz,2H),7.99-7.95(m, 3H),7.92(d,J=7.4Hz,1H),7.88(d,J=8.2Hz,2H),7.73(dd,J=8.5,1.8Hz,1H),7.53-7.48(m,2H), 7.44(d,J=8.6Hz,1H),7.38-7.34(m,3H),7.32(d,J=7.8Hz,2H),4.33-4.31(m,4H),2.06(bs,4H).

[0054] 2) Synthesis of the compound represented by formula (DSB-4)

[0055] Compound II-4 (63 mg, 0.09 mmol) and cyanoacetic acid (38 mg, 0.45 mmol) were added to the reaction flask, dissolved in a mixed solvent of acetonitrile (2 ml) and chloroform (2 ml), and then piperidine (0.5 ml) was slowly added dropwise, and the mixture was heated under reflux for 6 h. After the reaction was completed, the reaction solution was put into a large amount of water and extracted with dichloromethane, which was repeated three times, and the organic layers were combined. Then, the mixture was washed with a saturated NaCl solution, the solvent was removed by rotary evaporation, and the mixture was purified by column chromatography (V DCM :V MeOH =12:1) to obtain orange solid DSB-4 (42 mg, 61%).

[0056] Compound represented by formula (DSB-4): melting point: 240-243°C. 1H NMR (400MHz, DMSO) δ8.83(d,J=1.4Hz,1H),8.79-8.73(m,2H),8.60(d,J=1.4Hz,1H ),8.25(t,J=8.8Hz,2H),8.15(d,J=7.6Hz,1H),8.12-8.03(m,4H),8.00(d,J=7.2Hz ,2H),7.93-7.91(m,3H),7.86-7.79(m,1H),7.74-7.57(m,4H),7.46(dd,J=14.1,6 .8Hz,2H),7.24(dd,J=14.3,7.1Hz,2H),4.45(bs,4H),1.92(bs,4H).HRMS(ESI)m / z Calculate for C 49 H 35 N 6 O 2 S + [M+H] + 771.2542, found 771.2540.

[0057] Example 5 Synthesis of the compound represented by formula (DSB-5):

[0058]

[0059] 1) Synthesis of the compound represented by formula (II-5)

[0060] The Shrek reaction bottle was added with compound 4-(4-bromophenyl)pyridine (45 mg, 0.18 mmol), biboric acid pyranoside (135 mg, 0.6 mmol), PdCl 2 (dppf) (10 mg) and potassium acetate (156 mg, 1.2 mmol), vacuum nitrogen was replaced three times, and then solvent 1,4-dioxane (10 ml) was added, heated to react for 5 h, and IVe was synthesized; compound III (140 mg, 0.2 mmol), Pd (PPh 3 ) 4 (15 mg) and saturated potassium carbonate (198 mg, 1.44 mmol, 2M) aqueous solution, and continue to reflux for 5 hours. After the reaction is completed, the reaction solution is put into water and extracted with dichloromethane, which is repeated three times, and the organic layers are combined. Then, it is washed with saturated NaCl solution, the solvent is removed by rotary evaporation, and the resultant is purified by column chromatography (V DCM :V MeOH =20:1) to obtain an orange-yellow solid II-5 (70 mg, 48%).

[0061] Compound represented by formula (II-5): melting point: 190-194°C.1 H NMR (400 MHz, CDCl 3 )δ 1 H NMR(400MHz,Chloroform-d)δ10.08(s,1H),8.73(d,J=1.9Hz,1H),8.39(d,J=1.7Hz ,1H),8.23-8.15(m,4H),8.12-8.09(m,1H),7.98(d,J=8.3Hz,2H),7.93-7.86(m,4H ),7.74-7.64(m,4H),7.57(dd,J=7.4,1.5Hz,1H),7.51-7.46(m,4H),7.40-7.34(m, 2H),7.32(d,J=7.4Hz,2H),7.29(d,J=2.7Hz,2H),4.33-4.30(m,4H),2.06(bs,4H).

[0062] Synthesis of the compound represented by formula (DSB-5)

[0063] Compound II-5 (62 mg, 0.08 mmol) and cyanoacetic acid (34 mg, 0.4 mmol) were added to the reaction flask, dissolved in a mixed solvent of acetonitrile (2 ml) and chloroform (2 ml), and then piperidine (0.2 ml) was slowly added dropwise, heated to reflux, and reacted for 6 hours. After the reaction was completed, the reaction solution was put into a large amount of water and extracted with dichloromethane, repeated three times, and the organic layers were combined. Then it was washed with a saturated NaCl solution, the solvent was removed by rotary evaporation, and the mixture was purified by column chromatography (V DCM :V MeOH =12:1) to obtain orange-yellow solid DSB-5 (34 mg, 48%).

[0064] Compound represented by formula (DSB-5): melting point: 249-255°C. 1 H NMR (400 MHz, CDCl 3)δ8.74-8.71(m,3H),8.37(d,J=1.5Hz,1H),8.21(d,J=7.4Hz,2H),8.18-8.16(m,3H),8.11(dd,J =8.5,1.6Hz,1H),8.06(d,J=8.3Hz,2H),7.92(d,J=2.4Hz,2H),7.87(d,J=8.3Hz,2H),7.82(d,J= 8.4Hz,2H),7.74(dd,J=8.5,1.6Hz,1H),7.65(d,J=5.0Hz,2H),7.51(d,J=8.0Hz,1H),7.47(d,J= 8.7Hz,2H),7.39-7.34(m,3H),7.31-7.29(m,2H),4.33-4.31(m,4H),2.06(bs,4H).HRMS(ESI)m / z calcd for C 55 H 39 N 6 O 2 S + [M+H] + 847.2855, found847.2853.

[0065] Example 6 Application of biscarbazole compounds as Z907 co-sensitizers:

[0066] When used as a dye sensitizer, the application includes the following steps:

[0067] Dissolve the biscarbazole compound and dye Z907 in CH 3 Cl-CH 3 OH mixed solvent to obtain a mixed solution of biscarbazole compounds and Z907 (concentration of 3×10 -4 mol·L -1 ); the CH 3 Cl-CH 3 CH 3 Cl and CH 3 The volume ratio of OH is 10:1;

[0068] Double-layer TiO prepared by screen printing 2 Nanoparticle film as photoelectrode: First, a 12 μm thick layer of 20 nm TiO2 was printed on the conductive glass FTO. 2 The particles were calcined in a muffle furnace at 450°C for 30 min. The calcined membrane was cooled to room temperature and then immersed in 0.04 mol·L -1 TiCl 4 The membrane was pretreated with water solution at 70 °C for 30 min, and then the membrane was removed from TiCl 4The mixture was taken out from the aqueous solution and rinsed with water and ethanol respectively, and dried with a hair dryer. After calcination again at 450°C in a muffle furnace for 30 min, a double-layer TiO 2 Nanoparticle film photoelectrode.

[0069] The double-layer TiO 2 The nanoparticle film photoelectrode was cooled to 80°C and then immersed in the mixed solution of the biscarbazole compound and Z907 prepared in Example 1-5, and sensitized at room temperature for 24 hours to obtain a TiO2 loaded with biscarbazole compound and Z907 compound. 2 electrode.

[0070] Preparation of platinum counter electrode: H 2 PtCl 6 The aqueous solution was printed on FTO conductive glass. 2 PtCl 6 The surface of the FTO conductive glass was moistened with the aqueous solution, dried, and then sintered in a muffle furnace at 400° C. for 20 min to obtain a platinum counter electrode.

[0071] The double-layer TiO 2 The nanoparticle film photoelectrode and the platinum counter electrode were assembled into a sandwich structure, and the electrolyte was dripped into the edge of the sandwich structure and introduced into the battery using the capillary permeation principle to form a dye-sensitized solar cell (DSSC). 2 Under light intensity irradiation, the current-voltage curve of the DSSC assembled by the biscarbazole compound and Z907 was measured, and the performance parameter results are shown in Table 1:

[0072] Table 1 Performance parameters of DSSCs assembled from biscarbazole compounds

[0073]

[0074]

[0075] It can be seen from Table 1 that the dye-sensitized solar cells assembled with the biscarbazole compounds of the present invention and Z907 as dye sensitizers have good photoelectric conversion efficiency, which is 4.18-6.31%, which is higher than that of the solar cells sensitized by Z907 alone, adding new applicable substances to the screening of co-sensitizers of Z907.

[0076] The contents described in this specification are merely an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms described in the embodiments. The protection scope of the present invention is also limited to the equivalent technical means that can be thought of by those skilled in the art based on the inventive concept.

Claims

1. A biscarbazole compound, characterized in that: Its molecular structure is shown in Formula DSB-1, Formula DSB-2, Formula DSB-3, Formula DSB-4 or Formula DSB-5; 2. A method for preparing a biscarbazole compound according to claim 1, characterized in that: The method comprises the following steps: dissolving a compound represented by formula II-1, formula II-2, formula II-3, formula II-4 or formula II-5 and cyanoacetic acid in a solvent, adding an alkaline substance, heating under stirring and reflux reaction, and after the reaction is completed, concentrating the reaction solution to remove the solvent, dissolving the obtained concentrate in an eluent, separating and purifying it through column chromatography silica gel, collecting the eluent and evaporating the eluent to obtain a target product such as a compound represented by formula DSB-1, formula DSB-2, formula DSB-3, formula DSB-4 or formula DSB-5; The structural formula of the compound represented by formula II-1, formula II-2, formula II-3, formula II-4 or formula II-5 is as follows:

3. The method for preparing a biscarbazole compound according to claim 2, characterized in that: The heating reflux reaction time is 6-10h.

4. The method for preparing a biscarbazole compound according to claim 2, characterized in that: The solvent is a mixed solution of at least two of chloroform, toluene and acetonitrile, preferably a mixed solution of toluene and acetonitrile.

5. The method for preparing a biscarbazole compound according to claim 2, characterized in that: The molar ratio of the compound represented by formula II-1, formula II-2, formula II-3, formula II-4 or formula II-5, cyanoacetic acid and the alkaline substance is 1:1.2 to 5:12 to 61, preferably 1:2:

20.

6. The method for preparing a biscarbazole compound according to claim 2, characterized in that: The alkaline substance is piperidine.

7. The method for preparing a biscarbazole compound according to claim 2, characterized in that: The ratio of the amount of the compound represented by Formula II-1, Formula II-2, Formula II-3, Formula II-4 or Formula II-5 to the volume of the solvent is 1:20-50, the unit of the amount of the substance is mmol, and the unit of volume is mL.

8. The method for preparing a biscarbazole compound according to claim 2, characterized in that: The eluent is a mixed solvent of dichloromethane and methanol, and the volume ratio of dichloromethane to methanol is 12:

1.

9. Use of the biscarbazole compound according to claim 1 in preparing a dye sensitizer.

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