JP-2026076122-A - Compound, hole transport material, and photoelectric conversion element using the hole transport material

Abstract

[Problem] To provide a compound useful as a hole transport material for photoelectric conversion elements that can efficiently extract electric current. [Solution] Compound represented by general formula (1): (In the formula, L1 to L3 are selected from the group represented by formula (2), H, alkyl group, alkoxy group, amino group, thio group, alkylsulfinyl group, alkylsulfonyl group, etc., and at least one of them is the group represented by formula (2).) [Selection Diagram] Figure 1

Inventors

• 三枝 優太
• 加瀬 幸喜
• 高橋 秀聡
• 吉澤 由香

Assignees

• 保土谷化学工業株式会社

Dates

Publication Date

20260511

Application Date

20251010

Priority Date

20241023

Claims (6)

1. Compounds represented by the following general formula (1): In general formula (1), L1 to L3 are independent of each other. The group represented by the following general formula (2), hydrogen atom, halogen atom, hydroxyl group, Linear or branched alkyl groups having 1 to 20 carbon atoms, which may have substituents. A linear or branched alkenyl group having 2 to 20 carbon atoms, which may have substituents. A linear or branched alkoxy group having 1 to 20 carbon atoms, which may have substituents. A aryloxy group having 6 to 30 carbon atoms, which may have substituents; an amino group having 0 to 50 carbon atoms, which may have substituents. A thio group having 0 to 20 carbon atoms, which may have substituents. A alkylsulfinyl group having 1 to 20 carbon atoms, which may have substituents. A alkylsulfonyl group having 1 to 20 carbon atoms, which may have substituents. A substituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted heterocyclic group having 5 to 30 ring-forming atoms, At least one of L1 to L3 is a group represented by the following general formula (2): In general formula (2), R1 to R20 are each independent of each other. hydrogen atom, Linear or branched alkyl groups having 1 to 20 carbon atoms, which may have substituents. A linear or branched alkenyl group having 2 to 20 carbon atoms, which may have substituents. A cycloalkyl group having 3 to 10 carbon atoms, which may have substituents. A linear or branched alkoxy group having 1 to 20 carbon atoms, which may have substituents. An aryloxy group having 6 to 30 carbon atoms, which may have substituents. An amino group having 0 to 20 carbon atoms, which may have substituents, or a thio group having 0 to 20 carbon atoms, A1 to A3 represent nitrogen atoms or C( R1a ), and any two of A1 to A3 are nitrogen atoms. R 1a is, hydrogen atom, Linear or branched alkyl groups having 1 to 20 carbon atoms, which may have substituents. A linear or branched alkenyl group having 2 to 20 carbon atoms, which may have substituents. A cycloalkyl group having 3 to 10 carbon atoms, which may have substituents. A linear or branched alkoxy group having 1 to 20 carbon atoms, which may have substituents. An aryloxy group having 6 to 30 carbon atoms, which may have substituents. An amino group having 0 to 20 carbon atoms, which may have substituents, or a thio group having 0 to 20 carbon atoms, which may have substituents.
2. In the above general formula (1), L1 is hydrogen atom, An amino group having 0 to 50 carbon atoms, which may have substituents. A thio group having 0 to 20 carbon atoms, which may have substituents. A alkylsulfinyl group having 1 to 20 carbon atoms, which may have substituents. A alkylsulfonyl group having 1 to 20 carbon atoms, which may have substituents. The compound according to claim 1, wherein the compound is an aromatic hydrocarbon group having 6 to 20 carbon atoms, which may have substituents, or a heterocyclic group having 5 to 30 ring-forming atoms, which may have substituents.
3. The compound according to claim 1, wherein the compound represented by the general formula (1) is a compound represented by the following general formula (3) or general formula (4): In general formulas (3) and (4), L1 , L2 , A1 to A3 , and R1 to R20 are defined as in general formulas (1) and (2), respectively, except that L1 and L2 in general formula (3) represent groups other than those represented in general formula (2), and L1 in general formula (4) represents groups other than those represented in general formula (2).
4. The compound according to claim 1, wherein in the general formula (2), R1 to R20 are hydrogen atoms or linear or branched alkoxy groups having 1 to 20 carbon atoms, which may have substituents.
5. A hole transport material comprising the compound described in any one of claims 1 to 4.
6. A photoelectric conversion element using the hole transport material described in claim 5.

Description

This invention relates to a compound, a hole transport material, and a photoelectric conversion element using the hole transport material. In recent years, solar power generation has attracted attention as a clean energy source, and the development of solar cells is thriving. Among these, the development of solar cells using perovskite materials in the photoelectric conversion layer (hereinafter also referred to as "perovskite solar cells") is attracting attention as a next-generation solar cell that is low-cost and can be manufactured using solution processes (Patent Document 1, Non-Patent Documents 1 and 2). In perovskite solar cells, hole transport materials are often used within the device. The main purposes are: to improve photoelectric conversion efficiency by enhancing the selective hole transport function, and to protect the perovskite material, which is susceptible to moisture and oxygen, by bonding the hole transport material to the perovskite photoelectric conversion layer (Non-Patent Literature 3). Spiro-OMeTAD, a spirobifluorene-based organic compound, is widely used as a standard hole transport material. However, there are few reports of hole transport materials that contribute more significantly to photoelectric conversion characteristics than Spiro-OMeTAD. International Publication No. 2017/104792 J. Am. Chem. Soc., 2009, Vol. 131, pp. 6050–6051Science, 2012, Vol. 388, pp. 643–647Chem. Sci., 2019, Vol. 10, pp. 6748–6769 This is a schematic cross-sectional view showing the configuration of a photoelectric conversion element according to one embodiment of the present invention. The embodiments of the present invention will be described in detail below. While the descriptions of the constituent elements below may be based on representative embodiments and specific examples of the present invention, the present invention is not limited to such embodiments or specific examples. In this specification, numerical ranges expressed using "~" mean a range that includes the numbers before and after "~" as the lower and upper limits. When numerical ranges are described in steps, the upper and lower limits of each numerical range, as well as the numbers described in the examples, can be arbitrarily combined. Furthermore, in this specification, "transparent" and "translucent" mean that the transmittance of light used for photoelectric conversion is 50% or more, for example, 80% or more, 90% or more, or 99% or more. Note that the transmittance of light can be measured using an ultraviolet-visible spectrophotometer. <Compound> The compound according to the present invention, represented by the general formula (1) above, will be described in detail below. In general formula (1), L1 to L3 each independently represent a group represented by general formula (2), a hydrogen atom, a halogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 20 carbon atoms which may be substituted, a linear or branched alkenyl group having 2 to 20 carbon atoms which may be substituted, a linear or branched alkoxy group having 1 to 20 carbon atoms which may be substituted, an aryloxy group having 6 to 30 carbon atoms which may be substituted, an amino group having 0 to 50 carbon atoms which may be substituted, a thio group having 0 to 20 carbon atoms which may be substituted, an alkylsulfinyl group having 1 to 20 carbon atoms which may be substituted, an alkylsulfonyl group having 1 to 20 carbon atoms which may be substituted, an aromatic hydrocarbon group having 6 to 30 carbon atoms which may be substituted, or a heterocyclic group having 5 to 30 ring-forming atoms which may be substituted. Examples of "halogen atoms" represented by L1 to L3 include fluorine, chlorine, bromine, and iodine atoms. In the "linear or branched alkyl groups having 1 to 20 carbon atoms, which may have substituents" represented by L1 to L3 , specific examples of "linear or branched alkyl groups having 1 to 20 carbon atoms" include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, isopentyl group, n-hexyl group, 2-ethylhexyl group, heptyl group, octyl group, isooctyl group, nonyl group, and decyl group. In the "linear or branched alkenyl groups having 2 to 20 carbon atoms that may have substituents" represented by L1 to L3 , specific examples of "linear or branched alkenyl groups having 2 to 20 carbon atoms" include ethenyl group (vinyl group), 1-propenyl group, 2-propenyl group (allyl group), 1-methylethenyl group, 1-butenyl group, 2-butenyl group, 1-pentenyl group, 1-hexenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, and linear or branched alkenyl groups having 2 to 20 carbon atoms formed by the bonding of multiple of these alkenyl groups. In the "linear or branched alkoxy groups having 1 to 20 carbon atoms, which may have substituents" represented by L1 to L3 , specific examples of "linear or branched alkoxy gr