Compound, preparation method and use thereof and perovskite solar cell containing same
The present disclosure provides a compound having a structure of formula (I), where R1 and R2 are defined in the specification. In addition, the present disclosure further provides a preparation method and use of the compound of formula (I), in particular to a perovskite solar cell including the compound of formula (I). This compound as a hole transport material has the advantages in that the use of additives can be avoided, thereby improving the photoelectric conversion efficiency and stability of the cell.
1. A compound having a structure of formula (I),
wherein R1 is trivalent phenyl, optionally 1,3,4-benzenetriyl;
R2 is a single bond, C 2 -C 6 conjugated alkenylene or an unsaturated 5-membered or 6-membered ring group containing heteroatoms selected from O, S, or Se; and optionally, R2 is single bond vinylidene furylidene thiophenylene or selenophenylene.
2. The compound according to claim 1 , wherein the compound of formula (I) is a compound of formula (I-1), formula (I-2) or formula (I-3),
3. The compound according to claim 1 , wherein the compound has a HOMO energy level ranging from −5.05 eV to −5.30 eV, optionally ranging from −5.1 eV to −5.2 eV, and a charge mobility ranging from 1.0×10 −4 cm 2 V −1 s −1 to 8.0×10 −4 cm 2 V −1 s −1 optionally ranging from 2.0×10 −4 cm 2 V −1 s −1 to 6.0×10 −4 cm 2 V −1 s −1 .
4. A method for preparing a compound according to claim 1 , comprising the steps of:
1) Preparing a compound of formula (II):
coupling reaction of 4,4′-dimethoxydiphenylamine and an iodobenzene dibromide of formula (1) to form an intermediate (2), coupling reaction of the intermediate (2) and 4-borate-4′,4′-dimethoxytriphenylamine of formula (3) to generate an intermediate (4), and coupling reaction of the intermediate (4) and 2-(4-bromophenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane of formula (5) to obtain the compound of formula (II);
2) Preparing a compound of formula (III):
coupling reaction of 4,4′-dimethoxydiphenylamine and a compound of formula (6) to form an intermediate (7), and coupling reaction of the intermediate (7) and p-methoxyaniline of formula (8) to generate the compound of formula (III); and
3) preparing a compound of formula (I):
coupling reaction of the compound of formula (II) and the compound of formula (III) in the presence of a palladium catalyst and an alkali to obtain the compound of formula (I).
5. Use of the compound according to claim 1 as a hole transport material in a light-emitting device, wherein the light-emitting device comprises an organic electroluminescent device, and a perovskite solar cell.
6. A perovskite solar cell, comprising a conductive glass, an electron transport layer, a perovskite layer, a hole transport layer, and a metal electrode, wherein the hole transport layer comprises the compound according to claim 1 .
7. The perovskite solar cell according to claim 6 , wherein the hole transport layer contains no additives selected from lithium salts, cobalt salts, or co-solvents, including one or more of bis(trifluoromethane) sulfonimide lithium salt, cobalt-base(III) bis-trifluoromethane sulfonimide salt, and 4-tert-butylpyridine.
8. The perovskite solar cell according to claim 6 , wherein the bole transport layer has a HOMO energy level ranging from −5.05 eV to −5.30 eV optionally ranging from −5.10 eV to −5.20 eV; and the perovskite layer has a valence band top energy level ranging from −5.30 eV to −5.60 eV, optionally ranging from −5.30 eV to −3.50 eV.
9. The perovskite solar cell according to claim 6 , wherein the HOMO energy level of the hole transport layer is greater than a valence band top energy level of the perovskite layer, with an energy level difference ranging from 0.35 eV to 0.05 eV, optionally ranging from 0.3 eV to 0.2 eV.
10. The perovskite solar cell according to claim 6 , wherein the hole transport layer has a thickness ranging from 5 nm to 100 nm, optionally ranging from 30 nm to 80 nm.
11. A method for preparing the perovskite solar cell according to claim 6 , comprising the steps for a hole transport layer:
dissolving the compound in an organic solvent to prepare a solution of a hole transport material; and
coating the solution of the hole transport material onto the surface of the perovskite layer, and removing the solvent to obtain the hole transport laver,
wherein, when the perovskite solar cell is a forward perovskite solar cell, the concentration of the compound in the solution of the hole transport material ranges from 20 mg/mL to 100 mg/ml; when the perovskite solar cell is an inverted perovskite solar cell, the concentration of the compound in the solution of the hole transport material ranges from 1 mg/ml to 50 mg/ml; and
wherein the organic solvent is toluene, chlorobenzene or dichloromethane.