Polymer hole transport material with spirofluorene xanthene core, synthetic method and application

Abstract

The invention belongs to the technical field of organic semiconductor photoelectricity, and particularly relates to a polymer hole transport material of a spirofluorene xanthene core, a synthesis method and application. The structure of the hole transport material is different from that of traditional poly [bis (4-phenyl) (2, 4, 6-trimethylphenyl) amine] (PTAA). Special functional groups such as an alkoxy group, a phosphate group, a carboxyl group, a phosphorus-oxygen group and the like are introduced into the molecules, and a spirofluorene xanthene nuclear molecule connection mode with a three-dimensional structure is introduced into the molecules. Compared with PTAA, the new molecule has obvious advantages in charge transmission performance, interface interaction on specific materials and chemical stability. Tests show that the material is expected to be applied to the field of organic electronic devices such as high-performance perovskite solar cells and perovskite light-emitting diodes, and a new material choice is provided for improving the performance of related devices.

Description

Technical Field

[0001] The present invention relates to a polymer hole transport material with a spirofluoreneoxanthene core, a synthesis method and an application thereof, belonging to the field of organic semiconductor optoelectronic technologies. Background Art

[0002] In the field of organic electronic devices, hole transport materials (HTMs) play a crucial role. In various devices such as organic light-emitting diodes (OLEDs) and perovskite solar cells (PSCs), the hole transport materials are responsible for transporting holes from the electrodes to the functional layers, and their performance directly affects the efficiency and stability of the devices. With the rapid development of organic electronic technologies, the demand for high-performance hole transport materials is becoming increasingly urgent. An ideal hole transport material should have a high hole mobility to ensure that holes can be transported quickly and efficiently, reduce charge recombination, and increase the current density of the device; it should have a suitable energy level matching, precisely fit with the energy levels of adjacent functional layers, reduce the energy barriers for charge injection and extraction, and improve the energy conversion efficiency; it should also have excellent chemical and thermal stabilities, maintain the stability of structure and performance under different environmental conditions, and extend the service life of the device.

[0003] Poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), as a commonly used hole transport material, has been widely applied in the fields of organic electronic devices such as perovskite solar cells and organic light-emitting diodes. However, PTAA has certain limitations. In terms of charge transport, its transport efficiency is difficult to meet the growing demands of high-performance devices, resulting in limited improvement in the energy conversion efficiency of the devices. At the same time, the interfacial interaction between PTAA and adjacent functional layer materials is weak, lacking effective chemical bonding and intermolecular forces, leading to large energy losses during the charge extraction and transport processes, and affecting the overall performance of the device. In addition, under complex environmental conditions, PTAA has insufficient chemical stability and is prone to structural changes and performance degradation, limiting the service life of the device. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a spirofluoreneoxanthene core polymer hole transport material, a synthesis method and an optoelectronic device based on this hole transport material.

[0005] In the first aspect, the present invention proposes a spirofluoreneoxanthene core polymer hole transport material with a chemical general formula shown in the following formula (I):

[0006]

[0007] In the formula, R1 to R3 are substituents;

[0008] Wherein, the substituent R1 is any one of hydrogen, halogen, alkoxy, thioalkoxy, and Cl-C16 alkyl, preferably, any one of hydrogen, fluorine, chlorine, bromine, iodine, methoxy, methylthio, and C1-C16 alkyl;

[0009] The substituents R2 and R3 are any one of a carboxyl group, a phosphate group, a diethyl phosphate group, a sulfonic acid group, a carbazole group, a substituted carbazole group, a triphenylamine group, a substituted triphenylamine group or a triphenylphosphoxy group, and R2 and R3 may be the same or different.

[0010] Furthermore, the hole transport material is any one of compounds i to vi having the following structures:

[0011]

[0012] In a second aspect, the present invention provides a method for synthesizing the hole transport material described in the first aspect, wherein the hole transport material is obtained by a Buch-wald coupling reaction, comprising the following steps:

[0013] S1, a step of preparing intermediate-1 by subjecting 2,7-dibromo-9-fluorenone and resorcinol to an affinity substitution reaction in a mixed solution of p-toluenesulfonic acid and toluene;

[0014]

[0015] S2, a step of subjecting the intermediate-1 to a nucleophilic substitution reaction with 1-bromobutane in a mixed solution of cesium carbonate and acetonitrile to prepare the intermediate-2;

[0016]

[0017] S3, a step of preparing a target product by a coupling reaction of intermediate-2 and aniline in a mixed solution of sodium tert-butoxide and toluene using tri(dibenzylideneacetone)palladium and tri-tert-butylphosphine tetrafluoroborate as catalyst;

[0018]

[0019] Furthermore, in step S1, the molar ratio of 2,7-dibromo-9-fluorenone, resorcinol and p-toluenesulfonic acid is 1:2-2.2:0.1-0.2; the heating reaction temperature is 100-110° C., and the heating reaction time is 10-24 h.

[0020] Furthermore, in step S2, the molar ratio of the intermediate-1,1-bromobutane to cesium carbonate is 1:2-2.5:4-4.5; the reaction temperature is 25-40° C., and the reaction time is 24-48 h.

[0021] Furthermore, in step S3, the molar ratio of the intermediate-2, aniline, sodium tert-butoxide, tri(dibenzylideneacetone)palladium and tri-tert-butylphosphine tetrafluoroborate is 1:1-1.2:1-3:0.02-0.03:0.04-0.06; the reaction temperature is 100-120°C, and the reaction time is 8-12h.

[0022] The preparation method of the spirofluorene xanthene core polymer hole transport material of the present invention adopts different synthesis schemes according to the linking unit and terminal unit to be prepared. The applicant first provides a synthesis method of a relatively specific product, aiming to guide those skilled in the art to use similar methods to complete the synthesis of other compounds.

[0023] The above method describes the preparation method of the polymer hole transport material of the spirofluorene xanthene core. By simply changing the method and selecting the corresponding raw materials, for example, using the corresponding substituents as raw materials in steps (S2) and (S3), the corresponding position substituted products can be obtained. According to the prior art, those skilled in the art can independently realize the substituted spirofluorene xanthene core polymer hole transport material.

[0024] Another object of the present invention is to provide an application of the hole transport material described in the first aspect in the preparation of a perovskite solar cell device.

[0025] The spirofluorene xanthene core polymer hole transport material of the present invention has the following outstanding advantages compared with the prior art:

[0026] (1) Special functional groups such as terminal phosphate and phosphoxy groups have strong interactions with the perovskite interface and can reduce the interface defects of the perovskite;

[0027] (2) The three-dimensional spirofluorene anthene core structure gives the material good thermal and chemical stability, while providing a better charge transfer channel;

[0028] (3) The synthesis and purification methods are simple, which is conducive to large-scale commercial preparation and application in organic electronic devices such as perovskite solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a structural diagram of a perovskite solar cell device used in the present invention;

[0030] Figure 2 The J / V curve of the perovskite solar cell prepared using the reference compound PTAA as the hole transport material;

[0031] Figure 3 The J / V curve of the perovskite solar cell prepared by using the compound 1 provided by the present invention as a hole transport material;

[0032] Figure 4 The J / V curve diagram of a perovskite solar cell prepared by using Compound 2 provided by the present invention as a hole transport material;

[0033] Figure 5 The J / V curve diagram of a perovskite solar cell prepared by using Compound 3 provided by the present invention as a hole transport material;

[0034] Figure 6 The J / V curve diagram of a perovskite solar cell prepared by using Compound 4 provided by the present invention as a hole transport material;

[0035] Figure 7 The J / V curve diagram of a perovskite solar cell prepared by using Compound 5 provided by the present invention as a hole transport material;

[0036] Figure 8 The J / V curve diagram of a perovskite solar cell prepared by using Compound 6 provided by the present invention as a hole transport material. Detailed implementation manners

[0037] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following combines the accompanying drawings and preferred embodiments to detail the specific implementation manners, structures, features, and their effects according to the present invention.

[0038] To overcome the above defects of PTAA, it is extremely urgent to develop a new type of organic polymer hole transport material. The spirofluoreneoxanthene-core polymer hole transport material involved in the present invention is expected to exhibit performance superior to PTAA in terms of charge transport, interfacial interaction, and chemical stability by introducing special functional groups and constructing a unique three-dimensional molecular structure, providing new possibilities for solving the deficiencies of existing materials, and having potential application value in the fields of organic electronic devices, energy storage and conversion, etc.

[0039] More specifically, the example compounds are selected from the following structures:

[0040]

[0041] Example 1

[0042] Synthesis of Compound 1

[0043]

[0044] (1) Synthesis of Intermediate-1

[0045]

[0046] 2,8-Dibromo-9-fluorenone (10.0 g, 29.59 mmol), resorcinol (6.52 g, 59.17 mmol) and p-toluenesulfonic acid (0.40 g, 2.28 mmol) were mixed in a round-bottom flask. Toluene (200 mL) was added, and the reaction mixture was heated at 100 °C for 10 h. The reaction was cooled to room temperature, a precipitate formed, and the mixture was separated by filtration. The crude product was dissolved in absolute ethanol (100 mL) and insoluble impurities were removed by filtration. The organic solution was concentrated and purified by flash column chromatography using petroleum ether:ethyl acetate (3:1), and dried in vacuo for 5 h to give 12.10 g of Intermediate-1 in 78% yield. 1 H NMR (500 MHz, Chloroform-d) δ 7.78 (d, J = 8.0 Hz, 2H), 7.60 (dd, J = 8.1, 2.2 Hz, 2H), 6.98 (d, J = 8.5 Hz, 2H), 6.95 (d, J = 2.2 Hz, 2H), 6.56 (dd, J = 8.5, 2.2 Hz, 2H), 6.24 (d, J = 2.3 Hz, 2H). 13 C NMR (125 MHz, Chloroform-d) δ 159.37, 153.27, 147.89, 139.07, 132.47, 129.35, 128.02, 123.93, 119.32, 116.49, 110.61, 102.21, 44.89. HRMS (ESI, m / z): [M+H] + calculated for C 25 H 15 Br2O3, 522.9367, found 522.9354.

[0047] (2) Synthesis of Intermediate-2

[0048]

[0049] Under nitrogen protection, Intermediate-1 (5.00 g, 9.58 mmol), Cs2CO3 (9.07 g, 27.83 mmol) and a stir bar were charged into a dry 100 mL round-bottom flask. Then 50 mL of acetonitrile was added and the mixture was stirred at room temperature. After 30 min, 1-bromohexane (2.62 g, 19.15 mmol) was added and the reaction was carried out overnight at room temperature. After the reaction was completed, methanol was added and the precipitate was obtained by filtration. Then the collected crude product was dissolved in dichloromethane and insoluble impurities were removed by filtration. The organic solution was concentrated and separated by column chromatography to give 4.60 g of Intermediate-2 in 75% yield. 11H NMR (500 MHz, Chloroform-d) δ 7.78 (d, J = 8.0 Hz, 2H), 7.60 (dd, J = 8.1, 2.2 Hz, 2H), 7.09 (d, J = 8.1 Hz, 2H), 6.95 (d, J = 2.4 Hz, 2H), 6.71 (dd, J = 8.1, 2.3 Hz, 2H), 6.52 (d, J = 2.2 Hz, 2H), 4.01 (t, J = 6.4 Hz, 4H), 1.78 (p, J = 6.7 Hz, 4H), 1.48 (dt, J = 13.9, 6.9 Hz, 4H), 0.98 (t, J = 7.0 Hz, 6H). 13 13C NMR (125 MHz, Chloroform-d) δ 160.73, 152.37, 147.89, 139.07, 132.47, 129.35, 127.79, 123.93, 119.32, 118.60, 110.45, 101.83, 68.35, 44.77, 31.04, 19.16, 13.77. HRMS (ESI, m / z): [M+H] + calculated for C 33 H 31 Br2O3, 635.0619, found 635.0596.

[0050] (3) Synthesis of Compound 1

[0051]

[0052] Under nitrogen protection, intermediate - 2 (3.00 g, 4.73 mmol), aniline (0.221 g, 2.36 mmol), sodium tert - butoxide (0.68 g, 7.09 mmol) and 100 mL of toluene were added to a three - necked flask, and then Pd2(dba)3 (0.045 g, 0.12 mmol) and (t - Bu)3P + BF4 - (0.09 g, 0.25 mmol) were added. The mixture was heated under reflux and stirred for 6 hours. After the reaction was completed, it was cooled to room temperature, and the insoluble impurities were filtered off. The organic phase was concentrated to obtain a crude product. Then the collected crude product was dissolved in dichloromethane and purified by flash column chromatography with an eluent of petroleum ether:dichloromethane (2:1). It was dried in vacuo for 5 hours to obtain 0.95 g of Compound 1 with a yield of 67%. 1HNMR(500MHz, Chloroform-d) δ 7.88–7.82 (m, 2H), 7.35 (dtd, J=29.8, 6.7, 1.4 Hz, 2H), 7.26 (d, J=2.1 Hz, 1H), 7.22 (d, J=1.3 Hz, 1H), 7.21–7.13 (m, 3H), 7.09 (d, J=8.1 Hz, 2H), 7.04 (dd, J=7.7, 1.2 Hz, 2H), 6.91–6.80 (m, 2H), 6.71 (dd, J=8.1, 2.3 Hz, 2H), 6.52 (d, J=2.2 Hz, 2H), 4.01 (t, J=6.4 Hz, 4H), 1.78 (p, J=6.7 Hz, 4H), 1.48 (dt, J=13.8, 6.9 Hz, 4H), 0.98 (t, J=7.0 Hz, 6H). 13 C NMR(125MHz, Chloroform-d) δ 160.73, 152.37, 145.51, 144.98, 144.00, 141.71, 139.84, 136.33, 129.40, 128.71, 127.79, 127.19, 126.67, 122.23, 121.01, 118.94, 118.43, 117.55, 114.46, 110.45, 101.83, 68.35, 44.86, 31.04, 19.16, 13.77. HRMS(ESI, m / z): [M+H] + calculated for C 39 H 37 NO3, 567.2773, found 567.2765.

[0053] Example 2

[0054] Synthesis of Compound 2

[0055]

[0056] Synthesis of Intermediate-3: Similar to the synthesis step of Intermediate-2, with a yield of 72%. 11H NMR (500 MHz, Chloroform-d) δ 7.78 (d, J = 8.0 Hz, 2H), 7.60 (dd, J = 8.1, 2.2 Hz, 2H), 7.09 (d, J = 8.0 Hz, 2H), 6.95 (d, J = 2.2 Hz, 2H), 6.71 (dd, J = 8.1, 2.3 Hz, 2H), 6.52 (d, J = 2.2 Hz, 2H), 4.06–3.94 (m, 12H), 1.97 (ddd, J = 12.0, 9.5, 8.9 Hz, 4H), 1.81–1.64 (m, 8H), 1.35 (td, J = 7.3, 0.7 Hz, 12H). 13 13C NMR (125 MHz, Chloroform-d) δ 161.17, 151.69, 138.96, 134.80, 132.27, 129.23, 127.29, 126.79, 123.76, 118.82, 110.29, 101.14, 67.97, 61.27, 58.50, 29.45, 26.21, 25.45, 21.51, 16.22. HRMS (ESI, m / z): [M+H] + calculated for C 41 H 49 Br2O9P2, 907.1198, found 907.1176.

[0057] Synthesis of Compound 2: Similar to the synthesis procedure of Compound 1, with a yield of 69%. 1 1H NMR (500 MHz, Chloroform-d) δ 7.88–7.82 (m, 2H), 7.35 (dtd, J = 29.8, 6.7, 1.4 Hz, 2H), 7.24–7.17 (m, 3H), 7.16 (d, J = 13.4 Hz, 1H), 7.09 (d, J = 8.0 Hz, 2H), 7.07–7.01 (m, 2H), 6.91–6.80 (m, 2H), 6.71 (dd, J = 8.1, 2.3 Hz, 2H), 6.52 (d, J = 2.2 Hz, 2H), 4.07–3.92 (m, 12H), 2.03–1.92 (m, 4H), 1.83–1.63 (m, 8H), 1.35 (td, J = 7.3, 0.7 Hz, 12H). 1313C NMR (125 MHz, Chloroform-d) δ 161.17, 151.69, 144.12, 140.68, 139.63, 136.59, 134.46, 134.08, 129.40, 128.71, 127.24, 126.85, 126.63, 122.27, 120.92, 118.57, 117.55, 114.50, 110.29, 101.14, 67.97, 61.27, 58.51, 29.45, 26.21, 25.45, 21.51, 16.22. HRMS (ESI, m / z): [M+H] + calculated for C 47 H 56 NO9P2, 840.3430, found 840.3429.

[0058] Example 3

[0059] Synthesis of Compound 3

[0060]

[0061] Synthesis of Intermediate-4: Similar to the synthesis steps of Intermediate-2, with a yield of 76%. 1 1H NMR (500 MHz, Chloroform-d) δ 7.78 (d, J = 8.0 Hz, 1H), 7.60 (dd, J = 8.1, 2.2 Hz, 1H), 7.09 (d, J = 8.0 Hz, 1H), 6.95 (d, J = 2.2 Hz, 1H), 6.71 (dd, J = 8.1, 2.3 Hz, 1H), 6.52 (d, J = 2.2 Hz, 1H), 3.99 (t, J = 6.0 Hz, 2H), 2.38 (t, J = 8.7 Hz, 2H), 1.77 (ttd, J = 7.1, 6.0, 0.9 Hz, 2H), 1.71–1.60 (m, 2H). 13 13C NMR (125 MHz, Chloroform-d) δ 177.15, 160.73, 152.37, 147.89, 139.07, 132.47, 129.35, 127.79, 123.93, 119.32, 118.60, 110.45, 101.83, 67.89, 44.77, 34.07, 28.92, 21.76. HRMS (ESI, m / z): [M+H] + calculated for C 35 H 31 Br2O7, 723.0416, found 723.0412.

[0062] Synthesis of Compound 3: Similar to the synthesis procedure of Compound 1, with a yield of 65%. 1 H NMR (500 MHz, Chloroform-d) δ 7.88–7.82 (m, 2H), 7.35 (dtd, J=29.9, 6.7, 1.4 Hz, 2H), 7.26 (d, J=2.1 Hz, 1H), 7.24–7.18 (m, 3H), 7.16 (d, J=13.4 Hz, 1H), 7.09 (d, J=8.1 Hz, 2H), 7.07–7.01 (m, 2H), 6.91–6.80 (m, 2H), 6.71 (dd, J=8.0, 2.3 Hz, 2H), 6.52 (d, J=2.2 Hz, 2H), 3.99 (t, J=6.0 Hz, 4H), 2.38 (d, J=17.4 Hz, 4H), 1.83–1.70 (m, 4H), 1.66 (qt, J=8.6, 6.2 Hz, 4H). 13 C NMR (125 MHz, Chloroform-d) δ 177.15, 160.73, 152.37, 145.51, 144.98, 144.00, 141.71, 139.84, 136.33, 129.40, 128.71, 127.79, 127.19, 126.67, 122.23, 121.01, 118.94, 118.43, 117.55, 114.46, 110.45, 101.83, 67.89, 44.86, 34.07, 28.92, 21.76. HRMS (ESI, m / z): [M+H] + calculated for C 41 H 38 NO7, 656.2648, found 656.2637.

[0063] Example 4

[0064] Synthesis of Compound 4

[0065]

[0066] Synthesis of Intermediate-5: Similar to the synthesis procedure of Intermediate-2, with a yield of 87%. 11H NMR (500 MHz, Chloroform-d) δ 7.97 (s, 4H), 7.78 (d, J = 8.0 Hz, 2H), 7.60 (dd, J = 8.1, 2.2 Hz, 2H), 7.09 (d, J = 8.1 Hz, 2H), 6.95 (d, J = 2.4 Hz, 2H), 6.71 (dd, J = 8.1, 2.3 Hz, 2H), 6.52 (d, J = 2.2 Hz, 2H), 3.97 (t, J = 5.4 Hz, 4H), 1.95 (dt, J = 11.9, 9.6 Hz, 4H), 1.80–1.71 (m, 4H), 1.71–1.66 (m, 3H), 1.66–1.61 (m, 1H). 13 13C NMR (125 MHz, Chloroform-d) δ 161.17, 151.69, 138.96, 134.80, 132.27, 129.23, 127.29, 126.79, 123.76, 118.82, 110.29, 101.14, 67.97, 58.50, 29.78, 26.48, 25.72, 21.38. HRMS (ESI, m / z): [M+H] + calculated for C 33 H 33 Br2O9P2, 794.9946, found 794.9932.

[0067] Synthesis of Compound 4: Similar to the synthesis procedure of Compound 1, with a yield of 79%. 1 1H NMR (500 MHz, Chloroform-d) δ 7.97 (s, 4H), 7.88–7.82 (m, 2H), 7.35 (dtd, J = 29.9, 6.7, 1.4 Hz, 2H), 7.26 (d, J = 2.1 Hz, 1H), 7.24–7.18 (m, 3H), 7.16 (d, J = 13.3 Hz, 1H), 7.09 (d, J = 8.1 Hz, 2H), 7.07–7.01 (m, 2H), 6.91–6.80 (m, 2H), 6.71 (dd, J = 8.1, 2.3 Hz, 2H), 6.52 (d, J = 2.2 Hz, 2H), 3.97 (t, J = 5.4 Hz, 4H), 2.00–1.90 (m, 4H), 1.82–1.61 (m, 8H). 13¹³C NMR (125 MHz, Chloroform-d) δ 161.17, 151.69, 144.12, 140.68, 139.63, 136.59, 134.46, 134.08, 129.40, 128.71, 127.24, 126.85, 126.63, 122.27, 120.92, 118.57, 117.55, 114.50, 110.29, 101.14, 67.97, 58.51, 29.78, 26.48, 25.72, 21.38. HRMS (ESI, m / z): [M+H] + calculated for C 39 H 40 NO₉P₂, 728.2178, found 728.2177.

[0068] Example 5

[0069] Synthesis of Compound 5

[0070]

[0071] Synthesis of Intermediate-6: Similar to the synthesis steps of Intermediate-2, with a yield of 74%. 1 ¹H NMR (500 MHz, Chloroform-d) δ 7.78 (d, J = 8.1 Hz, 2H), 7.75 (d, J = 2.3 Hz, 2H), 7.60 (dd, J = 8.1, 2.2 Hz, 2H), 7.48 (d, J = 2.4 Hz, 2H), 7.33 (dd, J = 8.2, 3.8 Hz, 4H), 7.08 (s, 2H), 6.95 (d, J = 2.3 Hz, 2H), 6.88 (ddd, J = 10.6, 8.2, 2.4 Hz, 4H), 6.71 (dd, J = 8.1, 2.3 Hz, 2H), 6.52 (d, J = 2.2 Hz, 2H), 4.26–4.18 (m, 4H), 4.04–3.97 (m, 4H), 3.83 (s, 12H), 1.89 (pt, J = 4.0, 1.8 Hz, 8H). 13 ¹³C NMR (125 MHz, Chloroform-d) δ 160.73, 155.05, 152.37, 147.89, 139.07, 137.13, 132.47, 129.35, 127.79, 123.93, 123.26, 119.32, 118.60, 115.79, 110.48, 105.38, 101.83, 67.77, 55.68, 44.77, 43.90, 26.64, 26.10. HRMS (ESI, m / z): [M+H]+ Calculated for C 61 H 53 Br2N2O7, 1085.2199, found 1085.2199.

[0072] Synthesis of Compound 5: Similar to the synthesis procedure of Compound 1, with a yield of 70%. 1 H NMR (500 MHz, Chloroform-d) δ 7.88–7.82 (m, 2H), 7.75 (d, J = 2.4 Hz, 2H), 7.48 (d, J = 2.3 Hz, 2H), 7.38 (td, J = 6.8, 1.4 Hz, 1H), 7.36–7.29 (m, 5H), 7.26 (d, J = 2.1 Hz, 1H), 7.22 (d, J = 1.3 Hz, 1H), 7.21–7.13 (m, 4H), 7.09 (d, J = 8.1 Hz, 2H), 7.07–7.01 (m, 2H), 6.92–6.86 (m, 5H), 6.82 (dd, J = 7.2, 1.6 Hz, 1H), 6.71 (dd, J = 8.1, 2.3 Hz, 2H), 6.52 (d, J = 2.2 Hz, 2H), 4.25–4.17 (m, 4H), 4.05–3.97 (m, 4H), 3.83 (s, 12H), 1.94–1.83 (m, 8H). 13 C NMR (125 MHz, Chloroform-d) δ 160.73, 155.05, 152.37, 145.51, 144.98, 144.00, 141.71, 139.84, 137.13, 136.33, 129.40, 128.71, 127.79, 127.19, 126.67, 123.26, 122.23, 121.01, 118.94, 118.43, 117.55, 115.79, 114.46, 110.48, 105.38, 101.83, 67.77, 55.68, 44.86, 43.90, 26.64, 26.10. HRMS (ESI, m / z): [M+H] + Calculated for C 67 H 60 N3O7, 1018.4431, found 1018.4431.

[0073] Example 6

[0074] Synthesis of Compound 6

[0075]

[0076] Synthesis of Intermediate-7: Similar to the synthesis steps of Intermediate-2, with a yield of 78%. 1 H NMR(500MHz,Chloroform-d)δ7.78(d,J=8.0Hz,2H),7.69–7.63(m,8H),7.63–7.52(m,10H),7.52–7.45(m,8H),7.20(dt,J=8.7,1.1Hz,4H),7.09(d,J=8.0Hz,2H),6.95(d,J=2.2Hz,2H),6.71(dd,J=8.1,2.3Hz,2H),6.52(d,J=2.2Hz,2H),4.02(t,J=5.8Hz,4H),2.63(tt,J=7.9,1.1Hz,4H),1.84–1.75(m,4H),1.67(qd,J=7.7,0.8Hz,4H). 13 C NMR(125MHz,Chloroform-d)δ161.17,151.69,143.59,138.96,134.80,132.75,132.37,132.03,131.68,129.30,128.36,127.29,126.79,123.76,118.82,110.29,101.14,67.82,58.50,35.35,29.13,27.58.HRMS(ESI,m / z):[M+H] + calculated for C 69 H 57 Br2O5P2,1187.2028,found1187.2028.

[0077] Synthesis of Compound 6: Similar to the synthesis steps of Compound 1, with a yield of 62%. 11H NMR (500 MHz, Chloroform-d) δ 7.88–7.82 (m, 2H), 7.69–7.63 (m, 8H), 7.62–7.52 (m, 8H), 7.52–7.44 (m, 8H), 7.35 (dtd, J=29.8, 6.7, 1.4 Hz, 2H), 7.22 (d, J=2.1 Hz, 1H), 7.21 (d, J=1.1 Hz, 1H), 7.21–7.13 (m, 6H), 7.09 (d, J=8.0 Hz, 2H), 7.07–7.01 (m, 2H), 6.91–6.80 (m, 2H), 6.71 (dd, J=8.1, 2.3 Hz, 2H), 6.52 (d, J=2.2 Hz, 2H), 4.02 (t, J=5.8 Hz, 4H), 2.63 (ddt, J=8.0, 7.1, 1.1 Hz, 4H), 1.84–1.75 (m, 4H), 1.67 (qd, J=7.6, 0.8 Hz, 4H). 13 13C NMR (125 MHz, Chloroform-d) δ 161.17, 151.69, 144.12, 143.59, 140.68, 139.63, 136.59, 134.46, 134.08, 132.75, 132.18, 131.68, 129.38, 128.71, 128.36, 127.24, 126.85, 126.63, 122.27, 120.92, 118.57, 117.55, 114.50, 110.29, 101.14, 67.82, 58.51, 35.35, 29.13, 27.58. HRMS (ESI, m / z): [M+H] + calculated for C 75 H 64 NO5P2, 1120.4260, found 1120.4260.

[0078] The preparation process and performance detection effect analysis of perovskite solar cell devices D1 to D8 prepared from the compounds of the present invention are described below to further illustrate in detail the uses and effects of the compounds of the present invention.

[0079] The structure of the perovskite solar cell device described in the present invention is as Figure 1 , where the preparation method of device D1 includes the following steps:

[0080] 1) First, use a cleaning agent, deionized water, acetone, and isopropanol to ultrasonically clean an indium tin oxide (ITO) substrate for 20 minutes, dry the substrate with a nitrogen gun, and then perform ultraviolet ozone treatment for 15 minutes;

[0081] 2) Preparation of hole transport layer (HTL): Poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) was dissolved in chlorobenzene solvent, spin-coated on top of ITO, and annealed at 120 °C for 20 min to remove adsorbed water molecules for standby;

[0082] 3) Preparation of perovskite thin film (perovskite layer): The concentration of the perovskite precursor solution was 1.5 M, and the perovskite thin film was prepared by the anti-solvent one-step method. Spin coating was divided into two stages. The speed in the first stage was 1000 rpms -1 , spin-coated for 5 s; the second stage was 5000 rpm s -1 spin-coated for 30 s. 200 μL of ethyl acetate was added dropwise to the center of the perovskite film as an anti-solvent 20 s before the end of the second stage. Finally, anneal at 100 °C for 30 min to obtain the final perovskite thin film;

[0083] 3) Preparation of electron transport layer (ETL) and hole blocking layer: A solution of PCBM was prepared using chlorobenzene with a concentration of 20 mg / mL -1 , spin-coated in one-step procedure (1500 rmp s -1 spin-coated for 45 s), and annealed at 100 °C for 10 min.

[0084] 4) Preparation of hole blocking layer: Finally, 120 μL of isopropanol solution of BCP was drop-coated to prepare the hole blocking layer (ITO);

[0085] 5) Preparation of back electrode: A vacuum evaporator (<2×10 -4 Pa) was used to evaporate 100 nm of silver to form the negative electrode.

[0086] The preparation method and process of device D2 are the same as those of D1, except for preparing the hole transport layer of the polymer hole transport material (Compound 1) provided by the present invention;

[0087] The preparation method and process of device D3 are the same as those of D1, except for preparing the hole transport layer of the polymer hole transport material (Compound 2) provided by the present invention;

[0088] The preparation method and process of device D4 are the same as those of D1, except for preparing the hole transport layer of the polymer hole transport material (Compound 3) provided by the present invention;

[0089] The preparation method and process of device D5 are the same as those of D1, except for preparing the hole transport layer of the polymer hole transport material (Compound 4) provided by the present invention;

[0090] The preparation method and process of device D6 are the same as those of D1, except for preparing the hole transport layer of the polymer hole transport material (Compound 5) provided by the present invention;

[0091] The preparation method and process of device D7 are the same as those of D1, except for the preparation of the hole transport layer of the polymer hole transport material (Compound 6) provided by the present invention.

[0092] Performance test of perovskite solar cells: The current-voltage characteristics curve (I-V) of the solar cells was recorded by a Keithley 2400 digital source meter. The light source was a xenon lamp (Osram XBO 450) to simulate AM 1.5 sunlight with an intensity of 1000 W / m 2 , calibrated by a silicon cell, and the test temperature was 25 °C. The J-V data of the test cells are shown in Table 1 and Figures 2 - 8 .

[0093] Table 1

[0094]

[0095] As can be seen from Table 1 and Figures 2 - 8 : When the spirofluorene xanthene polymer hole transport material of the present invention is applied in perovskite solar cells, the short-circuit density of the cells is greater than 20 mA / cm 2 , the open-circuit voltage is greater than 1.10 V, and the fill factor is greater than 70%. Under the simulated sunlight intensity of 1.5 AM, a photoelectric conversion efficiency greater than 18% is shown. Due to the introduction of special functional groups such as alkoxy, phosphate, carboxyl, phosphoxy groups, etc., and unique molecular connection methods. Compared with PTAA, the new molecule shows significant advantages in charge transport performance, interfacial interaction with specific materials, and chemical stability, and the prepared perovskite solar cell device shows excellent performance.

Claims

1. A polymeric hole transporting material with a spirofluoreneoxanthene core, characterized in that It has the chemical structure shown in formula (I): In the formula, R1 to R3 are substituents; Wherein, the substituent R1 is any one of hydrogen, halogen, alkoxy, thioalkoxy, and Cl-C16 alkyl, preferably, any one of hydrogen, fluorine, chlorine, bromine, iodine, methoxy, methylthio, and C1-C16 alkyl; The substituents R2 and R3 are any one of a carboxyl group, a phosphate group, a diethyl phosphate group, a sulfonic acid group, a carbazole group, a substituted carbazole group, a triphenylamine group, a substituted triphenylamine group or a triphenylphosphoxy group.

2. The hole transporting material according to claim 1, wherein It is any one of the compounds i to vi having the following structures:

3. A method for synthesizing a polymeric hole transport material with a spirofluoreneoxanthene core, characterized in that, include: S1, a step of preparing intermediate-1 by subjecting 2,7-dibromo-9-fluorenone and resorcinol to an affinity substitution reaction in a mixed solution of p-toluenesulfonic acid and toluene; S2, a step of subjecting the intermediate-1 to a nucleophilic substitution reaction with 1-bromobutane in a mixed solution of cesium carbonate and acetonitrile to prepare the intermediate-2; S3, a step of preparing a target product by a coupling reaction of intermediate-2 and aniline in a mixed solution of sodium tert-butoxide and toluene using tri(dibenzylideneacetone)palladium and tri-tert-butylphosphine tetrafluoroborate as catalyst; 4. The method according to claim 3, wherein In step S1, the molar ratio of 2,7-dibromo-9-fluorenone, resorcinol and p-toluenesulfonic acid is 1:2-2.2:0.1-0.2; the heating reaction temperature is 100-110° C., and the heating reaction time is 10-24 hours.

5. The method according to claim 3, wherein In step S2, the molar ratio of intermediate-1, 1-bromobutane and cesium carbonate is 1:2-2.5:4-4.5; the reaction temperature is 25-40° C., and the reaction time is 24-48 hours.

6. The method according to claim 3, wherein In step S3, the molar ratio of intermediate-2, aniline, sodium tert-butoxide, tri(dibenzylideneacetone)palladium and tri-tert-butylphosphine tetrafluoroborate is 1:1-1.2:1-3:0.02-0.03:0.04-0.06; the reaction temperature is 100-120° C., and the reaction time is 8-12 hours.

7. Use of the hole transport material according to claim 1 or 2 in a perovskite solar cell.

8. A hole transport material composition for perovskite solar cells, comprising the hole transport material according to claim 7.

9. A perovskite solar cell element, comprising the hole transport material according to claim 1 or 2, or the hole transport material composition according to claim 8. 10 . A perovskite solar cell using the perovskite solar cell element according to claim 9 .

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