JP7062283B2 - A novel porphyrin derivative, a method for producing a porphyrin derivative, a donor material, a photoelectric conversion device, and a method for manufacturing a photoelectric conversion device. - Google Patents

Description

The present invention relates to a novel porphyrin derivative, a method for producing a porphyrin derivative, a photoelectric conversion device, and a method for producing a photoelectric conversion device, and in particular, a porphyrin derivative suitable for use as a donor material, a method for producing the same, and the porphyrin derivative. The present invention relates to a photoelectric conversion device used as a donor material and a method for manufacturing the photoelectric conversion device.

As a countermeasure to the energy problem, the development of a solar cell, which is a kind of photoelectric conversion device, is attracting attention. Among them, organic thin-film solar cells having a thin film made of an organic material have been developed with a maximum efficiency of more than 13%, and some of them have begun to be put into practical use.

As the active layer of such an organic thin-film solar cell, a laminate of a donor layer (p-type layer) and an acceptor layer (n-type layer) is used, and a type (pn hetero) utilizing a heterojunction at the layer interface is used. There are two types: a type that uses a layer in which a donor and an acceptor are mixed and uses a heterojunction in the layer (called a bulk heterojunction type or a BHJ (bulk heterojunction) type). ..

Among these, in the BHJ type, since the donor and the acceptor are in an entangled state in the active layer, the area of the pn junction interface (charge separation interface) is increased, and the efficiency of charge separation can be improved. ..

The basic concept of the BHJ type was proposed in 1992, and since then it has become the mainstream configuration of organic thin-film solar cells. Among them, the coating-BHJ type, which forms an active layer by applying a solution in which a donor and an acceptor are mixed and then solidifying it, can reduce the cost of materials and manufacturing methods, and further, the active layer is large. It has a commercial advantage because it is easy to increase the area.

In the past, the coating-BHJ type often used a polymer as the donor material, but in recent years, small molecule donor materials have been attracting attention. Small molecule donor materials have the advantages of easier synthesis and purification and less variation in performance between lots than polymer donor materials. As small molecule donor materials, compounds with various skeletons such as phthalocyanine, diketopyrrolopyrrole, oligothiophene, and porphyrin are being investigated.

Among them, compounds having a porphyrin skeleton are abundant in nature, such as chlorophyll used in the photosynthetic mechanism of absorbing light energy to produce saccharides, and their structural modification is diverse and highly light-resistant. Due to its excellent properties and excellent absorbance yield, research on its application to organic EL and solar cells is progressing as well as in the field of life science.

The compound having a porphyrin skeleton has also been applied to the above-mentioned organic thin-film solar cell, and research examples of organic thin-film solar cells using a compound having a porphyrin skeleton (also referred to as a porphyrin derivative) have been known so far. Has been done.

Coating-BHJ type organic thin film solar cells using such a porphyrin derivative as a donor material are disclosed in, for example, Non-Patent Documents 1 to 6.

For example, these non-patent documents disclose an organic thin-film solar cell using a porphyrin derivative in which a diketopyrrolopyrrole (DPP) unit is linked to a porphyrin skeleton as a donor material. Some organic thin-film solar cells with conversion efficiencies of up to 9% have been reported.

Li, L .; Huang, Y .; Peng, J .; Cao, Y .; Peng, X. J. Mater. Chem. A. 2013, 1, 2144_2150. Qin, H .; Li, L .; Guo, F .; Su, S .; Peng, J .; Cao, Y .; Peng, X. Energy. Environ. Soc. 2014, 7, 1397_1401. Gao, K .; Li, L .; Lai, T .; Xiao, L .; Huang, Y .; Huang, F .; Peng, J .; Cao, Y .; Liu, F .; Russell, T. P .; Janssen , R.-A. J .; Peng, X. J. Am. Chem. Soc. 2015, 137, 7282_7285. Gao, K .; Miao, J .; Xiao, L .; Deng, W .; Kan, Y .; Liang, T .; Wang, C .; Huang, F .; Peng, J .; Cao, Y .; Liu, F .; Russell, T. P .; Wu, Hongbin, w .; Peng, X. Adv. Mater. 2016, 28, 4727_4733. Li, M .; Kao, K .; Wan, X .; Zhang, Q .; Kan, B .; Xia, R .; Liu, F .; Yang, X .; Feng, H .; ni, w .; Wang, Y .; Peng, J .; Zhang, H .; Liang, Z .; Yip, H.-L .; Peng, X .; Cao, Y .; Chen, Y. Nature Photonics. 2017, 11, 85_90 .. Hatano, J .; Obata, N .; Yamaguchi, S .; Yasuda, T .; Matsuo, Y. J. Mater. Chem. 2012, 22, 19258_19263.

The above-mentioned DPP has excellent optical characteristics and is used as a pigment or an ink, and also absorbs a wide range of wavelengths in the visible light region. It is considered that an efficient organic thin-film solar cell can be realized.

On the other hand, the coated-BHJ type organic thin-film solar cell has a structure in which the donor and the acceptor are entangled in the active layer, so that the charge transport path becomes complicated and the charge transport efficiency of electrons and holes decreases. Has been done.

Therefore, the present inventors have earnestly considered the composition of a porphyrin derivative suitable for use as a donor material in order to improve the charge transport efficiency of electrons or holes by improving the charge mobility and to improve the characteristics such as a long excitation lifetime. The study was carried out, the synthesis was successful, and the performance when used in an organic thin-film solar cell as a donor material was confirmed.

An object of the present invention is to provide a novel porphyrin derivative, a method for producing the same, and further to provide a suitable donor material for use in a photoelectric conversion device such as a solar cell. Another object of the present invention is to provide a photoelectric conversion device using the donor material and a method for manufacturing the same.

(1) The porphyrin derivative of the present invention is a porphyrin derivative represented by the following (Chemical Formula 1).

(2) The porphyrin derivative of the present invention is a porphyrin derivative represented by the following (Chemical Formula 2).

(3) In the method for producing a porphyrin derivative of the present invention, the TIPS group of the porphyrin derivative P1 is eliminated by the first reaction of the porphyrin derivative P1 and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 1). This is a method for producing a porphyrin derivative, which produces the porphyrin derivative of the following (chemical formula 1) by the second reaction between the porphyrin derivative P1 from which the TIPS group has been removed and DPP-Br.

For example, the second reaction is a reaction using a palladium catalyst.

(4) In the method for producing a porphyrin derivative of the present invention, the TIPS group of the porphyrin derivative P2 is eliminated by the first reaction of the porphyrin derivative P2 and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 2). This is a method for producing a porphyrin derivative, which produces the porphyrin derivative of the following (chemical formula 2) by the second reaction between the porphyrin derivative P2 from which the TIPS group has been removed and DPP-Br.

For example, the second reaction is a reaction using a palladium catalyst.

(5) The donor material of the present invention is a donor material for a photoelectric conversion device having a porphyrin derivative represented by the following (Chemical formula 1) or (Chemical formula 2).

(6) The photoelectric conversion device of the present invention has a first electrode, a charge transport layer provided above the first electrode, and a second electrode provided above the charge transport layer. The charge transport layer is a layer in which a donor material and an acceptor material are mixed, and has a porphyrin derivative represented by the following (general formula 1) as the donor material.

The porphyrin derivative represented by the above (general formula 1) is a porphyrin derivative represented by the following (chemical formula 1) or (chemical formula 2).

(7) In the method for manufacturing a photoelectric conversion device of the present invention, (a) a coating layer is formed by coating a liquid having a donor material, an acceptor material, and a solvent on the first conductor layer to be the first electrode. Steps of forming, (b) a step of forming a charge transport layer having the donor material and the acceptor material by solidifying the coating layer, (c) a second electrode above the charge transport layer. It has a step of forming a second conductor layer, and the donor material is a porphyrin derivative represented by the following (general formula 1).

The porphyrin derivative represented by the above (general formula 1) is a porphyrin derivative represented by the following (chemical formula 1) or (chemical formula 2).

The porphyrin derivative represented by the above (general formula 1) is after removing the TIPS group of the porphyrin derivative by the first reaction of the porphyrin derivative and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 3). , The TIPS group is removed, and the porphyrin derivative is produced by a second reaction with DPP-Br.

(8) The porphyrin derivative of the present invention is a porphyrin derivative represented by the following (formula 1).

For example, M is a divalent metal element. For example, M is an element selected from Zn, Ca and Fe, and R is H or (CH ₂ ) ₅ CH ₃ .

(9) In the method for producing a porphyrin derivative of the present invention, the TIPS group of the porphyrin derivative PM is removed by the first reaction of the porphyrin derivative PM and tetrabutylammonium fluoride (TBAF) shown in the following (chemical reaction formula 1). This is a method for producing a porphyrin derivative, which produces the porphyrin derivative of the following (formula 1) by a second reaction between the porphyrin derivative PM from which the TIPS group has been removed and DPP-Br after separation.

For example, M is a divalent metal element. For example, M is an element selected from Zn, Ca and Fe, and R is H or (CH ₂ ) ₅ CH ₃ . For example, the second reaction is a reaction using a palladium catalyst.

(10) The donor material for the photoelectric conversion device of the present invention has a porphyrin derivative represented by the following (formula 1).

For example, M is a divalent metal element. For example, M is an element selected from Zn, Ca and Fe, and R is H or (CH ₂ ) ₅ CH ₃ .

(11) The photoelectric conversion device of the present invention has a first electrode, a charge transport layer provided above the first electrode, and a second electrode provided above the charge transport layer. The charge transport layer is a layer in which a donor material and an acceptor material are mixed, and has a porphyrin derivative represented by the following (formula 1) as the donor material.

For example, M is a divalent metal element. For example, M is an element selected from Zn, Ca and Fe, and R is H or (CH ₂ ) ₅ CH ₃ .

(12) In the method for manufacturing a photoelectric conversion device of the present invention, (a) a coating layer is formed by applying a liquid having a donor material, an acceptor material, and a solvent above the first conductor layer to be the first electrode. It has a step of forming, (b) a step of forming a charge transport layer having the donor material and the acceptor material by solidifying the coating layer. Further, it has (c) a step of forming a second conductor layer to be a second electrode above the charge transport layer, and the donor material is a porphyrin derivative represented by the following (formula 1). be.

For example, M is a divalent metal element. For example, M is an element selected from Zn, Ca and Fe, and R is H or (CH ₂ ) ₅ CH ₃ .

Further, for example, the porphyrin derivative represented by the above (formula 1) is desorbed from the TIPS group of the porphyrin derivative by the first reaction of the porphyrin derivative and tetrabutylammonium fluoride (TBAF) shown in the following (chemical reaction formula 1). After separation, it is produced by a second reaction between the porphyrin derivative from which the TIPS group has been removed and DPP-Br.

The present inventors have succeeded in synthesizing a novel porphyrin derivative represented by the above (Chemical formula 1) or (Chemical formula 2). By using such a porphyrin derivative as a donor material, the characteristics of the photoelectric conversion device can be improved.

It is sectional drawing which shows typically the structure of the photoelectric conversion apparatus of Embodiment 1. FIG. It is sectional drawing which shows the manufacturing process of the photoelectric change apparatus of Embodiment 1. FIG. 1 ¹ HNMR spectrum of product 1. ¹³ CNMR spectrum of product 1. It is a COSY spectrum of product 1. It is an MS spectrum of product 1. ^{1 1} HNMR spectrum of product 2. ¹³ CNMR spectrum of product 2. It is an MS spectrum of product 2. It is an ultraviolet-visible absorption spectrum of product 1 (MgTEPDPP ₂ Ph ₂ ). It is an ultraviolet-visible absorption spectrum of product 2 (MgTEPDPP2 ( ₄ -n-hexyl-C ₆ H4) ₂ ). It is sectional drawing which shows the manufacturing process of the photoelectric conversion apparatus of Embodiment 3. FIG. ^{1 1} HNMR spectrum of product 2'.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Structure of photoelectric conversion device)
FIG. 1 is a cross-sectional perspective view schematically showing the configuration of the photoelectric conversion device of the present embodiment. The photoelectric conversion device of the present embodiment uses an organic material as a donor material or an acceptor material and has a thin-film active layer, and is therefore also called an organic thin-film solar cell. Donors are also referred to as electron donors, and acceptors are also referred to as electron acceptors.

The photoelectric conversion device shown in FIG. 1 includes a first electrode EL1, an active layer (also referred to as a charge transport layer) AL provided on the first electrode EL1, and a second electrode EL2 provided on the active layer AL. Have.

The active layer AL provided on the first electrode EL1 is a layer existing in a state where the donor material DO and the acceptor material AC are mixed (see FIG. 1). The active layer AL can be formed by applying a mixed solution of a donor material, an acceptor material, and a solvent (solvent) to form a coating layer, and then drying and solidifying the coating layer.

A buffer layer may be provided between the first electrode EL1 and the active layer AL. Further, a buffer layer may be provided between the active layer AL and the second electrode EL2. The first electrode EL1 and the second electrode EL2 are made of a conductive material (conductor), and at least one of the first electrode EL1 and the second electrode EL2 has light transmission. The first electrode EL1 may be provided on the substrate (support).

As the substrate, a transparent substrate can be used. As the transparent substrate, a glass substrate, a plastic film (flexible substrate), or the like can be used. As the first electrode EL1, ITO (indium tin oxide), indium zinc oxide, or the like can be used. As the second electrode EL2, a metal such as aluminum or silver, an alloy containing this metal, or the like is used. As the acceptor material, fullerenes, fullerene derivatives (fullerene compounds) and the like can be used.

(Porphyrin derivative)
Here, in the present embodiment, the porphyrin derivative represented by the following (Chemical formula 1) or (Chemical formula 2) is provided as the donor material.

The porphyrin derivative represented by this (Chemical formula 1) is [5,15-bis (2,5-bis (2-ethyl-hexyl) -3,6-di-thienyl-2-yl-2,5-dihydro-pyrrolo). [3,4-c] pyrrole-1,4-dione-5'-yl-ethynyl) -10,20-bis (phenylethynyl) -porphyrionate] magnesium (II). This may be indicated by the abbreviation of "MgTEPDPP ₂ Ph ₂ ".

The porphyrin derivative represented by this (Chemical formula 2) is [5,15-bis (2,5-bis (2-ethyl-hexyl) -3,6-di-thienyl-2-yl-2,5-dihydro-pyrrolo). [3,4-c] pyrrole-1,4-dione-5'-yl-ethynyl) -10,20-bis (4-hexyl-phenylethynyl) -porphyrionate] magnesium (II). This may be indicated by the abbreviation of "MgTEPDPP ₂ (4-n-hexyl-C ₆ H ₄ ) ₂ ".

In these porphyrin derivatives, two DDP (Diketopyrrolopyrrole) units and two phenyl units are linked to the porphyrin skeleton at trans positions (positions 5 and 15). Each of these four units is linked to the porphyrin skeleton via an ethynyl crosslink. The porphyrin derivative can be said to be a compound in which a π-conjugated compound is linked via a triple bond.

In addition, the above-mentioned porphyrin derivative coordinates magnesium as the central metal of the porphyrin skeleton. Therefore, the porphyrin derivative can be said to be an Mg / porphyrin / DPP complex.

Further, in the porphyrin derivative having the above-mentioned structure, the π-conjugation spreads in the molecule and the entire molecule becomes planar, so that the packing structure is stabilized. That is, as the stacking density of the molecules increases, the π-π stacking between the molecules improves. When such a porphyrin derivative is used as a donor material in an active layer, it has the following advantages.

(1) By connecting the DPP unit to the porphyrin skeleton, light in the visible light region can be efficiently absorbed. Further, by adopting a DA (D = donor: porphyrin, A = acceptor: DPP) structure in the donor material, the energy band gap can be narrowed and the photoelectric conversion efficiency can be improved.

(2) As described above, the charge mobility can be improved by improving the π-π stacking between molecules.

(3) By coordinating magnesium as the central metal of the porphyrin skeleton, the excitation lifetime can be extended.

As described above, by using the porphyrin derivative represented by the above (Chemical formula 1) or (Chemical formula 2) as a donor material, the characteristics of the photoelectric conversion device can be improved.

(Synthesis method of porphyrin derivative)
As shown in the following (reaction formula 1), the porphyrin derivative of the above (chemical formula 1) includes a porphyrin derivative P1 (also referred to as a precursor P1 or an intermediate P1), tetrabutylammonium fluoride (TBAF), and DPP-. It can be synthesized by a chemical reaction with Br.

The TIPS (Triisopropylsilyl) of the porphyrin derivative P1 is eliminated by the reaction of the porphyrin derivative P1 with tetrabutylammonium fluoride (TBAF). Then, the DPP unit is introduced by the Sonogashira coupling. Sonogashira coupling refers to a chemical reaction in which a terminal alkyne and an aryl halide are cross-coupled by the action of a palladium catalyst, a copper catalyst, and a base to obtain an aryl halide.

As the solvent for the elimination reaction of TIPS, for example, tetrahydrofuran [THF], water ( _H2O ) or the like is used. In the case of Sonogashira coupling, for example, tetrahydrofuran [THF] or triethylamine [NET ₃ ] is used as the solvent, and the catalyst is a palladium catalyst, a copper catalyst, a base, for example, tris (dibenzylideneacetone) dipalladium. (0) [Pd ₂ (dba) ₃ ], copper (I) iodide [CuI], triphenylphosphine [PPh ₃ ] and the like are used.

As shown in the following (reaction formula 2), the porphyrin derivative of the above (chemical formula 2) includes porphyrin derivative P2 (also referred to as precursor P2 or intermediate P2), tetrabutylammonium fluoride (TBAF), and DPP-. It can be synthesized by a chemical reaction with Br. The reaction mechanism is the same as in the case of the above (chemical formula 1).

(Manufacturing method of photoelectric conversion device)
An example of a method for manufacturing a photoelectric change device (organic thin film solar cell) will be described below. FIG. 2 is a cross-sectional view showing a manufacturing process of the photoelectric change device of the present embodiment.

As shown in FIG. 2A, the first electrode EL1 is formed on the light-transmitting substrate SUB. For example, ITO (Indium Tin Oxide) is formed as a conductor layer on the substrate SUB, and the first electrode EL1 is formed by patterning.

Next, the buffer layer BUF1 is formed on the first electrode EL1. For example, a buffer layer BUF1 is formed by applying a PEDOT: PSS aqueous solution, which is a conductive polymer solution, onto a substrate and drying it.

Next, as shown in FIG. 2B, the active layer AL is formed on the buffer layer BUF1. First, the solution for forming the active layer is prepared. The donor material and acceptor material are dissolved in a solvent and additives are added as needed. Additives are used, for example, to increase the solubility of donor and acceptor materials. The solution for forming the active layer is applied onto the buffer layer BUF1 and dried to form the active layer AL. After that, if necessary, the active layer AL is subjected to an annealing treatment (heat treatment).

Next, as shown in FIG. 2 (c), the buffer layer BUF2 is formed on the active layer AL. For example, a calcium layer is formed on the active layer AL as the buffer layer BUF2 by using, for example, a vacuum vapor deposition method.

Next, the second electrode EL2 is formed on the buffer layer BUF2. For example, an aluminum layer is formed on the buffer layer BUF2 as a conductor layer for the second electrode EL2 by using, for example, a vacuum vapor deposition method.

As the donor material, the porphyrin derivative represented by the above (Chemical formula 1) or (Chemical formula 2) is used.

As the acceptor material, for example, a fullerene derivative is used. As the solvent, for example, chlorobenzene or the like is used. As the additive, for example, ethanol, acetone, tetrahydrofuran [THF], pyrazine, triethylamine [NET ₃ ], pyridine and the like are used. The annealing temperature can be 100 ° C to 200 ° C. It is not necessary to perform annealing treatment. In particular, in the porphyrin derivative represented by the above (Chemical formula 1) or (Chemical formula 2), as described above, the condensability (crystallinity) is good due to the improvement of π-π stacking between molecules, so the annealing treatment is omitted. can do.

[Example]
Hereinafter, the present embodiment will be described in more detail by way of examples, but the present embodiment is not limited to the examples shown below.

(Example 1)
In this example, the porphyrin derivative (MgTEPDPP ₂ Ph ₂ ) shown in the above (Chemical formula 1) was produced by the chemical reaction shown in the following (Reaction formula 4).

Under a nitrogen atmosphere, 35.7 mg of porphyrin derivative P1 (precursor P1, also referred to as intermediate P1) and 2 mL of tetrahydrofuran [THF] are placed in 30 mL shrenk, and 1 mol / L tetrabutylammonium fluoride is added. 0.25 mL of the derivative [TBAF] and 0.3 mL of water ( _H2O ) were added, and the mixture was stirred at room temperature (about 25 ° C.) for 1 hour. Extracted with methylene chloride and water was transferred to a two-necked flask at 20 mL with a cannula, and 30.2 mg of the DPP precursor [DPP-Br] was added to tris (dibenzylideneacetone) dipalladium (0) [Pd ₂ ]. (Dba) ₃ ] was 1.14 mg, triphenylphosphine [PPh ₃ ] was 6.56 mg, copper (I) iodide [CuI] was 0.23 mg, triethylamine [NEt ₃ ] was 3 mL, and tetrahydrofuran [ THF] was added with 7 mL, and the mixture was heated and stirred at 85 ° C. for 30 minutes. The crude product was removed from the origin by silica gel column chromatography and then purified by GPC (gel permeation chromatography) to obtain 30.0 mg of product 1. The yield of product 1 was 74%. This yield was determined from the ratio of the number of moles of the porphyrin derivative P1 and the product 1.

(inspection)
It was verified as follows that the product 1 obtained by the above step was a porphyrin derivative represented by the above (chemical formula 1).

FIG. 3 is a ¹ HNMR spectrum of product 1 and FIG. 4 is a ¹³ CNMR spectrum of product 1. FIG. 5 is a COSY spectrum of product 1. FIG. 6 is an MS spectrum of product 1. In the NMR spectrum, the vertical axis shows the relative intensity of the proton signal, and the horizontal axis shows the chemical shift (δ) value.

From the NMR spectra shown in FIGS. 3 and 4, it can be confirmed that the product 1 is the porphyrin derivative represented by the above (chemical formula 1). Further, the COSY spectrum of the product 1 shown in FIG. 5 also confirms that the product 1 is the porphyrin derivative represented by the above (chemical formula 1). The molecular weight (found) of product 1 obtained from the MS spectrum of product 1 shown in FIG. 6 is 1624.6248, which is the molecular weight (calcd) 1624.6288 of the above (Chemical formula 1). It is a good match.

As described above, the porphyrin derivative (MgTEPDPP ₂ Ph ₂ ) represented by the above (chemical formula 1) was successfully synthesized.

(Example 2)
In this example, the porphyrin derivative (MgTEPDPP ₂ (4-n-hexyl-C ₆ H ₄ ) ₂ ) shown in the above (Chemical formula 2) was produced by the chemical reaction shown in the following (Reaction formula 5).

Under a nitrogen atmosphere, 15.9 mg of porphyrin derivative P2 (precursor P2, also referred to as intermediate P2) and 1.2 mL of tetrahydrofuran [THF] were added to 30 mL shrenk, and 1 mol / L tetrabutyl was added. 0.15 mL of ammonium fluoride [TBAF] and 0.18 mL of water ( _H2O ) were added, and the mixture was stirred at room temperature (about 25 ° C.) for 1 hour. Extracted with methylene chloride and water was transferred to a two-necked flask with 20 mL using a cannula, and 18.1 mg of the DPP precursor [DPP-Br] and tris (dibenzylideneacetone) dipalladium (0) [Pd ₂ ] were added. (Dba) ₃ ] was 0.69 mg, triphenylphosphine [PPh ₃ ] was 3.93 mg, copper (I) iodide [CuI] was 0.14 mg, and triethylamine [NEt ₃ ] was 1.8 mL. 4.2 mL of tetrahydrofuran [THF] was added, and the mixture was heated and stirred at 85 ° C. for 1 hour. The crude product was purified from the origin using silica gel column chromatography and then purified by GPC (gel permeation chromatography) to obtain 20.0 mg of product 2. The yield of product 2 was 74%.

(inspection)
It was verified as follows that the product 2 obtained by the above step was a porphyrin derivative represented by the above (chemical formula 2).

FIG. 7 is a ¹ HNMR spectrum of product 2, and FIG. 8 is a ¹³ CNMR spectrum of product 2. FIG. 9 is an MS spectrum of product 2.

From the NMR spectra shown in FIGS. 7 and 8, it can be confirmed that the product 2 is the porphyrin derivative represented by the above (chemical formula 2). Further, the molecular weight (found) of the product 2 obtained from the MS spectrum of the product 2 shown in FIG. 9 is 1792.8146, and the molecular weight (calcd) of the above (chemical formula 2) is 1792.8166. It is a good match.

As described above, the porphyrin derivative (MgTEPDPP ₂ ( ₄ -n-hexyl-C ₆ H4) ₂ ) represented by the above (Chemical Formula 2) was successfully synthesized.

(Example 3)
The ultraviolet-visible absorption spectra of products 1 and 2 obtained by the steps shown in Examples 1 and 2 were measured. FIG. 10 is an ultraviolet-visible absorption spectrum of product 1 (MgTEPDPP ₂ Ph ₂ ), and FIG. 11 is an ultraviolet-visible absorption spectrum of product 2 (MgTEPDPP 2 (4-n-hexyl-C ₆ H ₄ ) ₂ ). be. The horizontal axis represents the wavelength (Wavelength, nm), and the vertical axis is the molar extinction coefficient ε.

As shown in FIG. 10, product 1 (MgTEPDPP ₂ Ph ₂ ) was found to have absorption over the entire visible light region. Further, as shown in FIG. 11, it was found that the product 2 (MgTEPDPP2 ( ₄ -n-hexyl-C ₆ H4) ₂ ) also had absorption in the entire visible light region. It is considered that such absorption in the visible light region is due to the introduction of the DPP unit. In addition, the bandgap narrows due to the spread of π-conjugation in the molecule, and there is a tendency for absorption to shift to the long wavelength side.

(Example 4)
Devices (photoelectric conversion device, photoelectric conversion element) were prepared and evaluated using the products 1 and 2 obtained by the steps shown in Examples 1 and 2 as donor materials.

A glass substrate (FLAT ITO manufactured by Geomatec) on which a patterned ITO film (first electrode) is formed is prepared, and ultrasonically cleaned with a cleaning solution, pure water, acetone, and IPA (isopropyl alcohol) for 15 minutes each. gone. The substrate was air _- dried and UV / O3 irradiation was performed for 15 minutes. Next, a conductive polymer solution PEDOT: PSS aqueous solution (Al4083 manufactured by Clevious) was spin-coated on the substrate to a film thickness of 40 nm, unnecessary parts were wiped off, and the mixture was heated and dried at 120 ° C. for 10 minutes under air. A buffer layer was formed. The substrate was then introduced into a nitrogen-filled glove box. The concentration of water and oxygen in the glove box is less than 0.1 ppm.

The solution for forming the active layer was prepared. The liquid preparation was performed in a nitrogen-filled glove box in which the concentration of water or oxygen was less than 0.1 ppm. To a mixture of the product 1 obtained by the step shown in Example 1 as a donor material and the fullerene derivative as an acceptor material, chlorobenzene was added as a solvent at a ratio of 10 mg / ml to the amount of the donor material. Further, an additive was added, and the mixture was heated and stirred at 60 ° C. in a glove box to dissolve the donor material and the acceptor material in a solvent to obtain a solution for forming an active layer.

After filtering this solution through a filter, the filtrate was applied onto the buffer layer by spin coating to form a coating film, and then slowly dried (solidified) in a petri dish for about 2 hours to form an active layer. .. Next, the active layer was subjected to an annealing treatment.

Then, a calcium layer was formed on the active layer as a buffer layer with a thickness of about 20 nm using a vacuum vapor deposition machine, and then an aluminum layer was formed on the buffer layer as a second electrode with a thickness of about 80 nm. It was formed using a vacuum vapor deposition machine.

A photoelectric conversion device was manufactured by the above steps. The produced photoelectric conversion device was irradiated with 1 SUN of light using a solar simulator, and the conversion efficiency (photoelectric conversion efficiency) was measured.

In the manufacturing process of the photoelectric conversion device, the conditions of the fullerene derivative, the additive, and the annealing temperature were changed according to the combinations shown in Table 1 to obtain No. 1 to No. The device shown in 23 was manufactured. The fullerene derivative PC ₆₁ BM is a derivative of fullerene C ₆₀ [6,6] -Phenyl C ₆₁ butyric acid methyl ester. Further, PC ₇₁ BM is a derivative of fullerene C ₇₀ [6,6] -Phenyl C ₇₁ butyric acid methyl ester. In the annealing column, the indication of "-" means that the annealing treatment has not been performed. Further, in the column of additives, the indication of "-" means that no additive is used.

The conversion efficiency PCE (%) was obtained from the product of the open circuit voltage (Voc), the short circuit current density (Jsc), and the fill factor (FF) (PCE = Voc × Jsc × FF). The results are shown in Table 1.

Further, the donor material was changed from the product 1 to the product 2 obtained by the step shown in Example 2, and the conditions of the fullerene derivative, the additive and the annealing temperature were changed by the combination shown in Table 2 to obtain No. 24-No. The photoelectric conversion device (device) shown in 29 was manufactured, and the conversion efficiency was determined. The results are shown in Table 2.

(Discussion)
As shown in Tables 1 and 2, the product 1 and the product 2, that is, the porphyrin derivative represented by the following (Chemical formula 1) or (Chemical formula 2), obtained by the steps shown in Examples 1 and 2 are used. By using it as a donor material, it was possible to obtain a photoelectric conversion device (device) having a conversion efficiency of 0.08% to 4.71%.

The maximum conversion efficiency when the porphyrin derivative represented by (Chemical formula 1) was used was 4.34%, and the maximum conversion efficiency when the porphyrin derivative represented by (Chemical formula 2) was used was 4.71%. .. The porphyrin derivative represented by (Chemical Formula 2) has high solubility in a solvent, and this point may have led to an increase in conversion efficiency.

In addition, the conversion efficiency of devices using pyridine as an additive tends to be high. It is possible that the addition of pyridine improved the solubility and led to an increase in conversion efficiency.

Further, when the annealing temperature was as high as 200 ° C., a decrease in conversion efficiency was observed. This is because the condensability (crystallinity) of the porphyrin derivative may have increased too much due to heating, and as a result, the conversion efficiency may have decreased.

As described above, the active layer AL of the present embodiment is a layer existing in a state where the donor material DO and the acceptor material AC are mixed (see FIG. 1). The donor material DO and the acceptor material AC each condense (crystallize) into particles, and form a carrier network by moderately separating the phases. Due to the high temperature annealing, the condensability (crystallinity) of the porphyrin derivative is increased and the particles become too large. Is considered to have decreased.

As described above, the porphyrin derivative represented by (Chemical Formula 1) or (Chemical Formula 2) is annealed because it has good condensability (crystallinity) due to the improvement of π-π stacking between molecules. High conversion efficiency is obtained even in devices that do not have it. For example, the annealing temperature is preferably less than 150 ° C, more preferably 100 ° C or lower.

Further, as the fullerene derivative, the conversion efficiency tended to be higher in the device using the PC ₇₁ BM than in the device using the PC ₆₁ BM.

(Embodiment 2)
In this embodiment, the synthetic raw material of the porphyrin derivative represented by the above (Chemical formula 1) or (Chemical formula 2) will be described.

(1) First, in Example 1, the synthesis of the porphyrin derivative P1 (also referred to as precursor P1 or intermediate P1) described with reference to (reaction formula 4) will be described.

This porphyrin derivative P1 can be produced, for example, by a chemical reaction shown in the following (reaction formula 6).

As shown in (Reaction Formula 6), a porphyrin derivative P1 can be synthesized by Sonogashira coupling using a porphyrin derivative P3 (also referred to as a precursor P3 or an intermediate P3) and phenylacetylene which is a reactant. can. Toluene, triethylamine [NEt ₃ ], and pyridine are used as a solvent, and the reaction is carried out at 80 ° C. for 3 hours.

(2) Next, the synthesis of the porphyrin derivative P3 (also referred to as precursor P3 or intermediate P3) will be described. The porphyrin derivative P3 can be produced, for example, by a chemical reaction shown in the following (reaction formula 7).

As shown in (Reaction equation 7), the porphyrin derivative P3 can be synthesized through a 4-step reaction from TIPS acetylene, which is a raw material MT. The first step (St1) is a step of changing the acetylene terminal to an aldehyde, and the second step (St2) is a step of forming a porphyrin ring skeleton. The third step (St3) is a step of inserting magnesium, and the fourth step (St4) is a step of dibromoization.

(3) Next, in Example 2, the synthesis of the porphyrin derivative P2 (also referred to as precursor P2 or intermediate P2) described with reference to (Reaction equation 5) will be described.

This porphyrin derivative P2 (also referred to as precursor P2 or intermediate P2) can be synthesized by substituting phenylacetylene, which is the reactant of the above (reaction formula 6), with 4-hexylphenylacetylene.

As described above, by chemically modifying the synthetic raw material of the porphyrin derivative in advance, the porphyrin derivative as the donor material can be given a further function.

That is, by using the porphyrin derivative represented by the following (general formula 1) as the donor material, the characteristics of the photoelectric conversion device can be further improved.

As R of the above general formula, for example, R1 to R7 shown in Table 3 are exemplified. In the case of the porphyrin derivative represented by the above (chemical formula 1), R is −H, which is shown as R1, and the reactant X is phenylacetylene. Further, in the case of the porphyrin derivative represented by the above (chemical formula 2), R becomes − (CH ₂ ) ₅ CH ₃ as shown in the column of “R2”, and the reactant is the substance shown in the column of “X”. be. In addition, the groups shown in R3 to R7 can be introduced by using the reactant X shown in Table 3.

As described above, by using the porphyrin derivative represented by the above (general formula 1) as a donor material, the characteristics of the photoelectric conversion device can be improved (charge mobility and excitation lifetime can be improved). Further, by introducing various groups as R, the physical properties can be adjusted.

Here, the porphyrin derivative represented by the above (general formula 1) is desorbed from the TIPS group of the porphyrin derivative by the first reaction of the porphyrin derivative and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 3). After that, it is produced by a second reaction between the porphyrin derivative from which the TIPS group has been removed and DPP-Br.

(Embodiment 3)
In this embodiment, a method of manufacturing a photoelectric conversion device using a continuous coating method called roll-to-roll will be described.

FIG. 12 is a cross-sectional view showing a manufacturing process of the photoelectric conversion device of the present embodiment. As shown in FIG. 12, the flexible substrate 10 is horizontally conveyed from the roller 11 to the roller 12. A first electrode and a buffer layer (not shown) are preliminarily formed on the flexible substrate 10 by using a continuous coating method or the like.

Then, between the rollers, a solution for forming the active layer (for example, the solution described in Examples 1 and 2) is applied from the slit coater 13, and the coating film is annealed by the cylindrical heater 14. As a result, the active layer AL is formed on the flexible substrate 10 and is wound around the roller 12.

After that, a buffer layer and a second electrode are formed on the active layer AL by using a continuous coating method or the like.

As described above, the active layer using the porphyrin derivative represented by the above (Chemical formula 1) or (Chemical formula 2) described in the first and second embodiments can be formed by a continuous coating method, and the device manufacturing cost can be reduced. The cost can be reduced, and the area of the active layer can be easily increased.

Further, as described above, the porphyrin derivative represented by the above (Chemical formula 1) or (Chemical formula 2) has good condensability (crystallinity), so that the annealing treatment can be omitted, and thus a shorter step. , It becomes possible to manufacture a photoelectric conversion device at low cost.

(Embodiment 4)
In the present embodiment, a device (photoelectric conversion device, photoelectric conversion element) using the porphyrin derivative of (Chemical Formula 2) described in the first embodiment as a donor material will be described based on Examples.

[Example]
(Example A)
A device (photoelectric conversion device, photoelectric conversion element) was produced and evaluated using the product 2 obtained by the step shown in Example 2 as a donor material.

A glass substrate (FLAT ITO manufactured by Geomatec) on which a patterned ITO film (first electrode) is formed is prepared, and ultrasonically cleaned with a cleaning solution, pure water, acetone, and IPA (isopropyl alcohol) for 15 minutes each. gone. The substrate was air _- dried and UV / O3 irradiation was performed for 15 minutes. Next, a conductive polymer solution PEDOT: PSS aqueous solution (Al4083 manufactured by Clevious) was spin-coated on the substrate to a film thickness of 40 nm, unnecessary parts were wiped off, and the mixture was heated and dried at 120 ° C. for 10 minutes under air. A buffer layer was formed. The substrate was then introduced into a nitrogen-filled glove box. The concentration of water and oxygen in the glove box is less than 0.1 ppm.

The solution for forming the active layer was prepared. The liquid preparation was performed in a nitrogen-filled glove box in which the concentration of water or oxygen was less than 0.1 ppm. To a mixture of the product 2 obtained by the step shown in Example 2 as a donor material and the fullerene derivative as an acceptor material, chlorobenzene was added as a solvent at a ratio of 10 mg / ml to the amount of the donor material. Further, an additive was added, and the mixture was heated and stirred at 60 ° C. in a glove box to dissolve the donor material and the acceptor material in a solvent to obtain a solution for forming an active layer.

After cooling this solution to room temperature, filter it, apply the filtrate on the buffer layer by spin coating, form a coating film, and then slowly dry (solidify) it in a petri dish for about 2 hours. An active layer was formed. Then, the active layer was annealed, if necessary.

Then, a calcium layer was formed on the active layer as a buffer layer with a thickness of about 20 nm using a vacuum vapor deposition machine, and then an aluminum layer was formed on the buffer layer as a second electrode with a thickness of about 80 nm. It was formed using a vacuum vapor deposition machine.

A photoelectric conversion device was manufactured by the above steps. The produced photoelectric conversion device was irradiated with 1 SUN of light using a solar simulator, and the conversion efficiency (photoelectric conversion efficiency) was measured.

Table A shows the conditions of the fullerene derivative, the additive, and the annealing temperature in the manufacturing process of the photoelectric conversion device. The fullerene derivative PC ₆₁ BM is a derivative of fullerene C ₆₀ [6,6] -Phenyl C ₆₁ butyric acid methyl ester. In the annealing column, the indication of "-" means that the annealing treatment has not been performed.

The conversion efficiency PCE (%) was obtained from the product of the open circuit voltage (Voc), the short circuit current density (Jsc), and the fill factor (FF) (PCE = Voc × Jsc × FF). The results are shown in Table 4.

(Discussion)
As shown in Table 4, a photoelectric conversion device (device) having a conversion efficiency of 5.73% can be obtained by cooling the mixed solution of the donor material and the acceptor material to room temperature and then using the filtered filtrate. rice field.

This Example A is No. 1 in Table 2 of Example 4 of the first embodiment. The conditions are similar to those of No. 28, but No. In the case of 28, the temperature of the filtrate of the mixed solution is 60 ° C., that is, the filtrate is hot-filtered, whereas in Example A, the filtrate is cooled to room temperature (25 ° C.). It is a filtrate after.

As described above, it is considered that the characteristics of the active layer were improved and the conversion efficiency was increased from 4.71% to 5.73% by filtering the mixed solution to room temperature (25 ° C.) and then filtering. ..

(Embodiment 5)
In this embodiment, a device (photoelectric conversion device, photoelectric conversion element) using the porphyrin derivative represented by (Chemical formula 1') or (Chemical formula 2') described later as a donor material will be described.

(Structure of photoelectric conversion device)
The photoelectric conversion device of the present embodiment can have the same configuration as the photoelectric conversion device described in the first embodiment (FIG. 1). The photoelectric conversion device of the present embodiment includes a first electrode EL1, an active layer (also referred to as a charge transport layer) AL provided on the first electrode EL1, and a second electrode EL2 provided on the active layer AL. , (See FIG. 1).

The active layer AL provided on the first electrode EL1 is a layer existing in a state where the donor material DO and the acceptor material AC are mixed. The active layer AL can be formed by applying a mixed solution of a donor material, an acceptor material, and a solvent (solvent) to form a coating layer, and then drying and solidifying the coating layer.

A buffer layer may be provided between the first electrode EL1 and the active layer AL. Further, a buffer layer may be provided between the active layer AL and the second electrode EL2. The first electrode EL1 and the second electrode EL2 are made of a conductive material (conductor), and at least one of the first electrode EL1 and the second electrode EL2 has light transmission. The first electrode EL1 may be provided on the substrate (support).

As the substrate, a transparent substrate can be used. As the transparent substrate, a glass substrate, a plastic film (flexible substrate), or the like can be used. As the first electrode EL1, ITO (indium tin oxide), indium zinc oxide, or the like can be used. As the second electrode EL2, a metal such as aluminum or silver, an alloy containing this metal, or the like is used. As the acceptor material, fullerenes, fullerene derivatives (fullerene compounds) and the like can be used.

(Porphyrin derivative)
As described above, in the present embodiment, the donor material has a porphyrin derivative represented by the following (Chemical formula 1') or (Chemical formula 2').

The porphyrin derivative shown in this (chemical formula 1') is [5,15-bis (2,5-bis (2-ethyl-hexyl) -3,6-di-thienyl-2-yl-2,5-dihydro- pyrrolo [3,4-c] pyrrole-1,4-dione-5'-yl-ethynyl) -10,20-bis (phenylethynyl) -porphyrionate] zinc (II). This may be indicated by the abbreviation of "ZnTEPDPP ₂ Ph ₂ ".

The porphyrin derivative represented by this (chemical formula 2') is [5,15-bis (2,5-bis (2-ethyl-hexyl) -3,6-di-thienyl-2-yl-2,5-dihydro- pyrrolo [3,4-c] pyrrole-1,4-dione-5'-yl-ethynyl) -10,20-bis (4-hexyl-phenylethynyl) -porphyrionate] zinc (II). This may be indicated by the abbreviation of "ZnTEPDPP ₂ (4-n-hexyl-C ₆ H ₄ ) ₂ ".

The above-mentioned porphyrin derivative is obtained by replacing the central metal of the porphyrin skeleton of the porphyrin derivative represented by (chemical formula 1) (chemical formula 2) described in the first embodiment with Zn from Mg.

As described in the first embodiment, the porphyrin derivative of the present embodiment also has two DDP (Diketopyrrolopyrrole) units and two phenyl units in the porphyrin skeleton at trans positions (positions 5 and 15). Is linked to. Each of these four units is linked to the porphyrin skeleton via an ethynyl crosslink. The porphyrin derivative can be said to be a compound in which a π-conjugated compound is linked via a triple bond.

In addition, the above-mentioned porphyrin derivative coordinates zinc as the central metal of the porphyrin skeleton. Therefore, the porphyrin derivative can be said to be a Zn / porphyrin / DPP complex.

Further, in the porphyrin derivative having the above-mentioned structure, the π-conjugation spreads in the molecule and the entire molecule becomes planar as in the case of (Chemical formula 1) and (Chemical formula 2) described in the first embodiment. Therefore, the packing structure is stabilized. That is, as the stacking density of the molecules increases, the π-π stacking between the molecules improves. When such a porphyrin derivative is used as a donor material in the active layer, it has the advantages (1) to (3) described in the first embodiment.

As described above, by using the porphyrin derivative represented by the above (Chemical formula 1') or (Chemical formula 2') as the donor material, the characteristics of the photoelectric conversion device can be improved.

(Synthesis method of porphyrin derivative)
As shown in the following (reaction formula 1'), the porphyrin derivative of the above (chemical formula 1') includes a porphyrin derivative P1'(also referred to as a precursor P1'and an intermediate P1') and tetrabutylammonium fluoride (TBAF). ) And DPP-Br can be synthesized by a chemical reaction.

The reaction between the porphyrin derivative P1'and tetrabutylammonium fluoride (TBAF) desorbs TIPS (Triisopropylsilyl) of the porphyrin derivative P1'. Then, the DPP unit is introduced by the Sonogashira coupling. Sonogashira coupling refers to a chemical reaction in which a terminal alkyne and an aryl halide are cross-coupled by the action of a palladium catalyst, a copper catalyst, and a base to obtain an aryl halide.

As the solvent for the elimination reaction of TIPS, for example, tetrahydrofuran [THF], water ( _H2O ) or the like is used. In the case of Sonogashira coupling, for example, tetrahydrofuran [THF] or triethylamine [NET ₃ ] is used as the solvent, and the catalyst is a palladium catalyst, a copper catalyst, a base, for example, tris (dibenzylideneacetone) dipalladium. (0) [Pd ₂ (dba) ₃ ], copper (I) iodide [CuI], triphenylphosphine [PPh ₃ ] and the like are used.

The porphyrin derivative of the above (chemical formula 2') is a porphyrin derivative P2'(also referred to as precursor P2', intermediate P2') and tetrabutylammonium fluoride (TBAF) as shown in the following (reaction formula 2'). ) And DPP-Br can be synthesized by a chemical reaction. The reaction mechanism is the same as in the case of the above (chemical formula 1').

(Manufacturing method of photoelectric conversion device)
The photoelectric change device (organic thin film solar cell) of the present embodiment can be formed by the manufacturing method of the photoelectric conversion device described in the first embodiment (FIG. 2).

Specifically, as described with reference to FIG. 2 in the first embodiment, first, the first electrode EL1 is formed on the light-transmitting substrate SUB (FIG. 2A). Next, the buffer layer BUF1 is formed on the first electrode EL1. Next, the active layer AL is formed on the buffer layer BUF1 (FIG. 2 (b)). First, the solution for forming the active layer is prepared. The donor material and acceptor material are dissolved in a solvent and additives are added as needed. Additives are used, for example, to increase the solubility of donor and acceptor materials. The solution for forming the active layer is applied onto the buffer layer BUF1 and dried to form the active layer AL. After that, if necessary, the active layer AL is subjected to an annealing treatment (heat treatment). Next, the buffer layer BUF2 is formed on the active layer AL (FIG. 2 (c)). Next, the second electrode EL2 is formed on the buffer layer BUF2. As the material and forming method of each layer, the same material and forming method as in the case of the first embodiment can be used.

As the donor material, the porphyrin derivative represented by the above (Chemical formula 1') or (Chemical formula 2') is used.

As the acceptor material, for example, a fullerene derivative is used. As the solvent, for example, chlorobenzene or the like is used. As the additive, for example, ethanol, acetone, tetrahydrofuran [THF], pyrazine, triethylamine [NET ₃ ], pyridine and the like are used. The annealing temperature can be 100 ° C to 200 ° C. It is not necessary to perform annealing treatment. In particular, in the porphyrin derivative represented by the above (Chemical formula 1') or (Chemical formula 2'), as described above, the condensability (crystallinity) is good due to the improvement of the π-π stacking between the molecules, so that the annealing treatment is performed. Can be omitted.

[Example]
Hereinafter, the present embodiment will be described in more detail by way of examples, but the present embodiment is not limited to the examples shown below.

(Example B)
In this example, the porphyrin derivative (ZnTEPDPP ₂ (4-n-hexyl-C ₆ H ₄ ) ₂ ) shown in the above (Chemical formula 2') was produced by the chemical reaction shown in the following (Reaction formula 5'). ..

Under a nitrogen atmosphere, 37.6 mg of porphyrin derivative P2'(also referred to as precursor P2'and intermediate P2') and 4 mL of tetrahydrofuran [THF] are placed in 20 mL shrenk, and 1 mol / L tetra. 0.34 mL of butylammonium fluoride [TBAF] was added, and the mixture was stirred at room temperature (about 25 ° C.) for 30 minutes. Extracted with methylene chloride and water was transferred to a two-necked flask at 20 mL with a cannula, and 41.0 mg of the DPP precursor [DPP-Br] was added to tris (dibenzylideneacetone) dipalladium (0) [Pd ₂ ]. (Dba) ₃ ] was 1.56 mg, triphenylphosphine [PPh ₃ ] was 8.92 mg, copper (I) iodide [CuI] was 0.32 mg, and triethylamine [NEt ₃ ] was 4.4 mL. 9.6 mL of tetrahydrofuran [THF] was added, and the mixture was heated and stirred at 85 ° C. for 4 hours. The crude product was removed from the origin by silica gel column chromatography and then purified by GPC (gel permeation chromatography) to obtain 44.9 mg of product 2'. The yield of product 2'was 72%. This yield was determined from the ratio of the number of moles of the porphyrin derivative P2'and the product 2'.

(inspection)
It was verified as follows that the product 2'obtained by the above step was a porphyrin derivative represented by the above (chemical formula 2').

FIG. 13 is a ¹ HNMR spectrum of product 2'. From the NMR spectrum shown in FIG. 13, it can be confirmed that the product 2'is the porphyrin derivative represented by the above (chemical formula 2').

As described above, the porphyrin derivative (ZnTEPDPP ₂ ( _{4-n-hexyl-C 6H 4 ) 2} ) represented by the above (chemical formula 2') was successfully synthesized.

In this example, the porphyrin derivative represented by (Chemical formula 2') was produced, but the porphyrin derivative represented by the above-mentioned (Chemical formula 1') also has the chemical reaction shown in the above-mentioned (Reaction formula 1'). Can be generated by.

(Example C)
A device (photoelectric conversion device, photoelectric conversion element) was produced and evaluated using the product 2'obtained by the step shown in Example B as a donor material.

A glass substrate (FLAT ITO manufactured by Geomatec) on which a patterned ITO film (first electrode) is formed is prepared, and ultrasonically cleaned with a cleaning solution, pure water, acetone, and IPA (isopropyl alcohol) for 15 minutes each. gone. The substrate was air _- dried and UV / O3 irradiation was performed for 15 minutes. Next, a conductive polymer solution PEDOT: PSS aqueous solution (Al4083 manufactured by Clevious) was spin-coated on the substrate to a film thickness of 40 nm, unnecessary parts were wiped off, and the mixture was heated and dried at 120 ° C. for 10 minutes under air. A buffer layer was formed. The substrate was then introduced into a nitrogen-filled glove box. The concentration of water and oxygen in the glove box is less than 0.1 ppm.

The solution for forming the active layer was prepared. The liquid preparation was performed in a nitrogen-filled glove box in which the concentration of water or oxygen was less than 0.1 ppm. Chlorobenzene was added to the mixture of the product 2'obtained by the step shown in Example B as the donor material and the fullerene derivative as the acceptor material at a ratio of 10 mg / ml to the amount of the donor material as a solvent. In addition, an additive was further added, and the mixture was heated and stirred at 60 ° C. in a glove box to dissolve the donor material and the acceptor material in a solvent to obtain a solution for forming an active layer.

After filtering this solution through a filter, the filtrate was applied onto the buffer layer by spin coating to form a coating film, and then slowly dried (solidified) in a petri dish for about 2 hours to form an active layer. .. Then, the active layer was annealed, if necessary.

Then, a calcium layer was formed on the active layer as a buffer layer with a thickness of about 20 nm using a vacuum vapor deposition machine, and then an aluminum layer was formed on the buffer layer as a second electrode with a thickness of about 80 nm. It was formed using a vacuum vapor deposition machine.

A photoelectric conversion device was manufactured by the above steps. The produced photoelectric conversion device was irradiated with 1 SUN of light using a solar simulator, and the conversion efficiency (photoelectric conversion efficiency) was measured.

Table B shows the conditions of the fullerene derivative, the additive, and the annealing temperature in the manufacturing process of the photoelectric conversion device. The fullerene derivative PC ₆₁ BM is a derivative of fullerene C ₆₀ [6,6] -Phenyl C ₆₁ butyric acid methyl ester. In the annealing column, the indication of "-" means that the annealing treatment has not been performed.

The conversion efficiency PCE (%) was obtained from the product of the open circuit voltage (Voc), the short circuit current density (Jsc), and the fill factor (FF) (PCE = Voc × Jsc × FF). The results are shown in Table 5.

(Discussion)
As shown in Table 5, the conversion efficiency is 0.20% by using the product 2'obtained by the step shown in Example B, that is, the porphyrin derivative represented by the following (Chemical formula 2') as the donor material. The photoelectric conversion device (device) of the above was obtained.

In this example, the porphyrin derivative represented by (Chemical formula 2') was used as a donor material to form a photoelectric conversion device, but the porphyrin derivative represented by the above-mentioned (Chemical formula 1') was also used as a donor material. A photoelectric conversion device can be formed.

(Embodiment 6)
In this embodiment, the synthetic raw material of the porphyrin derivative represented by the above (Chemical formula 1') or (Chemical formula 2') will be described.

(1) First, the synthesis of the porphyrin derivative P1'(also referred to as precursor P1' or intermediate P1'), which is the starting material of the above (reaction formula 1'), will be described.

This porphyrin derivative P1'can be produced, for example, by the steps [a] to [c] shown in the following (reaction formula A), (reaction formula B) and (reaction formula C).

[A] Step

As shown in (Reaction Formula A), chloroform [CHCl ₃ ] and trifluoroacetic acid [TFA] are allowed to act on the porphyrin derivative P3 (precursor P3, also referred to as intermediate P3), and Mg, which is the central metal of the porphyrin skeleton, is allowed to act. Pull out. The porphyrin derivative P3 can be produced by the chemical reaction shown in (reaction formula 7) of the second embodiment as described above.

[B] Step

Then, as shown in (Reaction equation B), chloroform [CHCl ₃ ] and zinc acetate [Zn (OAc) ₂ ] were allowed to act on the product of (Reaction equation A) above, and Zn was added to the center of the porphyrin skeleton. Introduce. As a result, the porphyrin derivative P3'in which Mg, which is the central metal of the porphyrin skeleton of the porphyrin derivative P3, is replaced with Zn can be produced.

[C] Step

Next, as shown in (Reaction formula C), the porphyrin derivative P3', which is the product of the above (Reaction formula B), and phenylacetylene, which is the reactant, are used to obtain the porphyrin derivative P1'by Sonogashira coupling. Can be synthesized. Toluene, triethylamine [NEt ₃ ], and pyridine are used as a solvent, and the reaction is carried out at 80 ° C. for 3 hours.

(2) Next, the synthesis of the porphyrin derivative P2'(also referred to as precursor P2' or intermediate P2'), which is the starting material of the above (reaction formula 5'), will be described.

The porphyrin derivative P2'(also referred to as precursor P2' or intermediate P2') can be synthesized by substituting phenylacetylene, which is the reactant of the above (reaction formula C), with 4-hexylphenylacetylene. That is, it can be synthesized by setting the above [c] step as the [c'] step. Specifically, it can be synthesized by the steps [a] to [c'] consisting of the above (reaction formula A), (reaction formula B) and the following (reaction formula C').

[C'] step

As described above, by chemically modifying the synthetic raw material of the porphyrin derivative in advance, the porphyrin derivative as the donor material can be given a further function.

That is, by using the porphyrin derivative represented by the following (general formula 1') as the donor material, the characteristics of the photoelectric conversion device can be further improved.

As R of the above general formula, R1 to R7 shown in Table 3 in the first embodiment are exemplified. In the case of the porphyrin derivative represented by the above (chemical formula 1'), R is −H, which is shown as R1, and the reactant X is phenylacetylene. Further, in the case of the porphyrin derivative shown in the above (chemical formula 2'), R becomes − (CH ₂ ) ₅ CH ₃ as shown in the column of “R2”, and the reactant is the substance shown in the column of “X”. Is. In addition, the groups shown in R3 to R7 can be introduced by using the reactant X shown in Table 3.

As described above, by using the porphyrin derivative represented by the above (general formula 1') as a donor material, the characteristics of the photoelectric conversion device can be improved (charge mobility and excitation lifetime can be improved). Further, by introducing various groups as R, the physical properties can be adjusted.

Here, the porphyrin derivative represented by the above (general formula 1') has the TIPS group of the porphyrin derivative obtained by the first reaction of the porphyrin derivative and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 3'). After desorption, it is produced by a second reaction between the porphyrin derivative from which the TIPS group has been desorbed and DPP-Br.

(Example D)
In this example, the synthetic raw material of the porphyrin derivative represented by the above (chemical formula 2') is used from the porphyrin derivative P3 in the steps [a] shown in the above (reaction formula A), (reaction formula B) and (reaction formula C'). -Generated by the [c'] step.

[A] Step In a 20 mL two-necked eggplant flask under a nitrogen atmosphere, 90.0 mg of the porphyrin derivative P3 and 8 mL of chloroform [CHCl ₃ ] were added, and 42 μL of trifluoroacetic acid [TFA] was added to room temperature (25 ° C.). Stirred for 1 hour. Extraction treatment was performed with chloroform and water. The crude product was purified using silica gel column chromatography to give 53.0 mg of product. The yield of the product of this step [a] was 59%. This yield was determined from the ratio of the porphyrin derivative P3 to the number of moles of the product.

[B] Under a nitrogen atmosphere, 53.0 mg of the product (porphyrin derivative) of step [a] and 6.13 mL of chloroform [CHCl ₃ ] were placed in a 20 mL two-necked eggplant flask, and zinc acetate [Zn] was further added. (OAc) ₂ ] 69.0 mg of the solution dissolved in 0.55 mL of methanol was added, and the mixture was stirred at 65 ° C. for 2 hours. The crude product was purified using silica gel column chromatography to obtain 50.4 mg of the product (porphyrin derivative P3'). The yield of the product of this step [b] was 90%. This yield was determined from the ratio of the number of moles of the product of step [a] to the porphyrin derivative P3'.

[C'] Step In a nitrogen atmosphere, 53.3 mg of porphyrin derivative P3', 19.2 mL of toluene, 4.81 mL of triethylamine [NET ₃ ] and 0.6 mL of pyridine were added to 50 mL shrenk, and then Tris ( Dibenzylideneacetone) dipalladium (0) [Pd ₂ (dba) ₃ ] at 3.30 mg, triphenylphosphine [PPh ₃ ] at 7.24 mg, and copper iodide (I) [CuI] at 3.09 mg. , 1-Etinyl-4-hexylbenzene 0.128 mL was added, and the mixture was heated and stirred at 85 ° C. for 30 minutes. The crude product was removed from the origin by silica gel column chromatography and then purified by GPC (gel permeation chromatography) to obtain 37.7 mg of product (porphyrin derivative P2'). The yield of the porphyrin derivative P2'was 57%. It was determined from the ratio of the number of moles of the porphyrin derivative P3'and the porphyrin derivative P2'.

Using this porphyrin derivative P2', the product 2'shown in Example B was produced, and it was confirmed that the porphyrin derivative was shown in the above (chemical formula 2').

The process for producing the porphyrin derivative P3'is not limited to the above steps [a] and [b]. For example, in the reaction formula 7 shown in the second embodiment, the Mg compound (MgBr2 _{- OEt2} ) of St3 is used. May be produced by using a Zn compound.

(Embodiment 7)
In this embodiment, a method of manufacturing a photoelectric conversion device using a continuous coating method called roll-to-roll will be described.

The active layer using the porphyrin derivative represented by the above (Chemical formula 1') or (Chemical formula 2') can be formed by the continuous coating method described in the third embodiment. In this case, the device manufacturing cost can be reduced, and further, the area of the active layer can be easily increased.

(Embodiment 8)
As described in the above embodiment, we succeeded in synthesizing novel porphyrin derivatives of (Chemical formula 1), (Chemical formula 2) and (Chemical formula 2'), and confirmed that they function as donor materials for photoelectric conversion devices. did it.

From the above examination, it can be seen that the porphyrin derivative represented by the following (formula 1) can be produced and is effective as a donor material.

The metal element M located at the center of the porphyrin skeleton is a divalent metal element. Specifically, the metal element M is an element selected from Mg, Zn, Ca and Fe. Further, by introducing various groups as R, the physical properties can be adjusted. As R, a group shown in Table 3 can be introduced, for example, H or (CH ₂ ) ₅ CH ₃ .

Further, the porphyrin derivative represented by (Formula 1) can be synthesized by the following (Chemical reaction formula 1). Specifically, the TIPS group of the porphyrin derivative PM was eliminated by the first reaction of the porphyrin derivative PM and tetrabutylammonium fluoride (TBAF), and then the TIPS group was eliminated, and then the porphyrin derivative PM and DPP- The porphyrin derivative of the above (formula 1) can be synthesized by the second reaction with Br. For the second reaction, for example, a palladium catalyst is used.

The porphyrin derivative of the above (formula 1) has a first electrode, a charge transport layer provided above the first electrode, and a second electrode provided above the charge transport layer. It can be used as an active layer (charge transport layer) of a conversion device. This active layer is a layer in which a donor material and an acceptor material are mixed, and has a porphyrin derivative represented by the above (formula 1) as a donor material.

Such a photoelectric conversion device can be manufactured by the following steps. First, a coating layer is formed by applying a liquid having a porphyrin derivative represented by the donor material (formula 1), an acceptor material, and a solvent above the first conductor layer to be the first electrode. The coating layer is then solidified to form a charge transport layer with a donor material and an acceptor material. Next, a second conductor layer to be a second electrode is formed above the charge transport layer.

Although the invention made by the present inventor has been specifically described above based on the embodiment, the present invention is not limited to the above embodiment and can be variously modified without departing from the gist thereof. Needless to say.

10 Flexible substrate 11 Roller 12 Roller 13 Slit coater 14 Heater AC acceptor material AL Active layer (charge transport layer)
BUF1 Buffer layer BUF2 Buffer layer DO Donor material EL1 1st electrode EL2 2nd electrode SUB substrate

Claims (24)

The porphyrin derivative represented by the following (Chemical formula 1).

The porphyrin derivative represented by the following (Chemical formula 2).

The porphyrin from which the TIPS group was removed after the TIPS group of the porphyrin derivative P1 was removed by the first reaction of the porphyrin derivative P1 and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 1). A method for producing a porphyrin derivative, which produces the porphyrin derivative of the following (chemical formula 1) by the second reaction of the derivative P1 and DPP-Br.

In the method for producing a porphyrin derivative according to claim 3,
The second reaction is a reaction using a palladium catalyst, which is a method for producing a porphyrin derivative. The porphyrin from which the TIPS group was removed after the TIPS group of the porphyrin derivative P2 was removed by the first reaction of the porphyrin derivative P2 and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 2). A method for producing a porphyrin derivative, which produces the porphyrin derivative of the following (chemical formula 2) by the second reaction of the derivative P2 and DPP-Br.

In the method for producing a porphyrin derivative according to claim 5.
The second reaction is a reaction using a palladium catalyst, which is a method for producing a porphyrin derivative. A donor material for a photoelectric conversion device having a porphyrin derivative represented by the following (Chemical formula 1) or (Chemical formula 2).

It has a first electrode, a charge transport layer provided above the first electrode, and a second electrode provided above the charge transport layer.
The charge transport layer is a layer in which a donor material and an acceptor material are mixed.
A photoelectric conversion device having a porphyrin derivative represented by the following (general formula 1) as the donor material.

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H.) In the photoelectric conversion device according to claim 8,
The porphyrin derivative represented by the above (general formula 1) is a porphyrin derivative represented by the following (chemical formula 1) or (chemical formula 2), which is a photoelectric conversion device.

(A) A step of forming a coating layer by coating a liquid having a donor material, an acceptor material, and a solvent on the first conductor layer to be the first electrode.
(B) A step of forming a charge transport layer having the donor material and the acceptor material by solidifying the coating layer.
(C) A step of forming a second conductor layer to be a second electrode above the charge transport layer.
Have,
The method for manufacturing a photoelectric conversion device, wherein the donor material is a porphyrin derivative represented by the following (general formula 1).

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H.) In the method for manufacturing a photoelectric conversion device according to claim 10,
The porphyrin derivative represented by (general formula 1) is a porphyrin derivative represented by the following (chemical formula 1) or (chemical formula 2), which is a method for producing a photoelectric conversion device.

In the method for manufacturing a photoelectric conversion device according to claim 10,
The porphyrin derivative represented by the above (general formula 1) is after removing the TIPS group of the porphyrin derivative by the first reaction of the porphyrin derivative and tetrabutylammonium fluoride (TBAF) shown in the following (reaction formula 3). A method for producing a photoelectric conversion device, which is produced by a second reaction between the porphyrin derivative from which the TIPS group has been removed and DPP-Br.

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H.) The porphyrin derivative represented by the following (formula 1).

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H, where M is Mg, Zn, Ca or Fe.) In the porphyrin derivative according to claim 13 ,
M is an element selected from Zn, Ca and Fe, and is an element.
The R is a porphyrin derivative, which is H or (CH ₂ ) ₅ CH ₃ . The TIPS group of the porphyrin derivative PM was desorbed by the first reaction of the porphyrin derivative PM and tetrabutylammonium fluoride (TBAF) shown in the following (chemical reaction formula 1), and then the TIPS group was desorbed. A method for producing a porphyrin derivative, which produces the porphyrin derivative of the following (formula 1) by a second reaction between the porphyrin derivative PM and DPP-Br.

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H, where M is Mg, Zn, Ca or Fe.) In the method for producing a porphyrin derivative according to claim 15 ,
M is an element selected from Zn, Ca and Fe, and is an element.
The method for producing a porphyrin derivative, wherein R is H or (CH ₂ ) ₅ CH ₃ . In the method for producing a porphyrin derivative according to claim 16 .
The second reaction is a reaction using a palladium catalyst, which is a method for producing a porphyrin derivative. A donor material for a photoelectric conversion device having a porphyrin derivative represented by the following (formula 1).

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H, where M is Mg, Zn, Ca or Fe.) In the donor material for the photoelectric conversion device according to claim 18 ,
M is an element selected from Zn, Ca and Fe, and is an element.
The R is a donor material for a photoelectric conversion device, which is H or (CH ₂ ) ₅ CH ₃ . It has a first electrode, a charge transport layer provided above the first electrode, and a second electrode provided above the charge transport layer.
The charge transport layer is a layer in which a donor material and an acceptor material are mixed.
A photoelectric conversion device having a porphyrin derivative represented by the following (formula 1) as the donor material.

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H, where M is Mg, Zn, Ca or Fe.) In the photoelectric conversion device according to claim 20 ,
M is an element selected from Zn, Ca and Fe, and is an element.
The R is a photoelectric conversion device, which is H or (CH ₂ ) ₅ CH ₃ . (A) A step of forming a coating layer by coating a liquid having a donor material, an acceptor material, and a solvent on the first conductor layer to be the first electrode.
(B) A step of forming a charge transport layer having the donor material and the acceptor material by solidifying the coating layer.
(C) A step of forming a second conductor layer to be a second electrode above the charge transport layer.
Have,
The method for manufacturing a photoelectric conversion device, wherein the donor material is a porphyrin derivative represented by the following (formula 1).

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H, where M is Mg, Zn, Ca or Fe.) In the method for manufacturing a photoelectric conversion device according to claim 22 ,
M is an element selected from Zn, Ca and Fe, and is an element.
The R is H or (CH ₂ ) ₅ CH ₃ , a method for manufacturing a photoelectric conversion device. In the method for manufacturing a photoelectric conversion device according to claim 22 ,
The porphyrin derivative represented by the formula (1) is obtained after removing the TIPS group of the porphyrin derivative by the first reaction of the porphyrin derivative and tetrabutylammonium fluoride (TBAF) shown in the following (chemical reaction formula 1). , A method for manufacturing a photoelectric conversion device, which is produced by a second reaction between the porphyrin derivative from which the TIPS group has been removed and DPP-Br.

(However, R is H, (CH ₂ ) ₅ CH ₃ , CF ₃ , N (CH ₃ ) ₂ , NO ₂ , CH ₂ - C (CH ₂ CH ₃ ) H-CH ₂ - CH ₂ - CH ₂ CH . ₃ or C (CH ₃ ) ₂ H, where M is Mg, Zn, Ca or Fe.)

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