Patent Application
20180362567
This application claims priority to Korean Patent Application No. 10-2017-0076822, filed on Jun. 16, 2017, in the Korean Intellectual Property Office, and all the benefits accruing therefrom under 35 U.S.C. § 119, the content of which is incorporated herein in its entirety by reference.
One or more embodiments relate to an organometallic compound, an organic light-emitting device including the organometallic compound, and a diagnostic composition including the organometallic compound.
Organic light-emitting devices (OLEDs) are self-emission devices, which have superior characteristics in terms of a viewing angle, a response time, a brightness, a driving voltage, and a response speed, and which produce full-color images.
In an example, an organic light-emitting device includes an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer includes an emission layer. A hole transport region may be disposed between the anode and the emission layer, and an electron transport region may be disposed between the emission layer and the cathode. Holes provided from the anode may move toward the emission layer through the hole transport region, and electrons provided from the cathode may move toward the emission layer through the electron transport region. The holes and the electrons recombine in the emission layer to produce excitons. These excitons transit from an excited state to a ground state, thereby generating light.
Meanwhile, luminescent compounds may be used to monitor, sense, or detect a variety of biological materials including cells and proteins. An example of the luminescent compounds includes a phosphorescent luminescent compound.
Various types of organic light emitting devices are known. However, there still remains a need in OLEDs having low driving voltage, high efficiency, high brightness, and long lifespan.
Aspects of the present disclosure provide an organometallic compound, an organic light-emitting device including the organometallic compound, and a diagnostic composition including the organometallic compound.
Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.
An aspect of the present disclosure provides an organometallic compound represented by Formula 1:
In Formula 1,
Another aspect of the present disclosure provides an organic light-emitting device including:
The organometallic compounds may act as a dopant in the organic layer.
Another aspect of the present disclosure provides a diagnostic composition including at least one organometallic compound represented by Formula 1.
These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the FIGURE which is a schematic view of an organic light-emitting device according to an embodiment.
Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.
It will be understood that when an element is referred to as being “on” another element, it can be directly in contact with the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.
It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers, and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the present embodiments.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
The term “or” means “and/or.” It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this general inventive concept belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims.
“About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” can mean within one or more standard deviations, or within ±30%, 20%, 10%, 5% of the stated value.
An organometallic compound according to an embodiment is represented by Formula 1 below:
M in Formula 1 may be beryllium (Be), magnesium (Mg), aluminum (Al), calcium (Ca), titanium (Ti), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn), gallium (Ga), germanium (Ge), zirconium (Zr), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), rhenium (Re), platinum (Pt), or gold (Au).
In an embodiment, M may be palladium or platinum, but embodiments of the present disclosure are not limited thereto.
In Formula 1, X1 to X4 may each independently be N or C, and X5 may be a single bond, O, S, B(R′), N(R′), P(R′), C(R′)(R″), Si(R′)(R″), Ge(R′)(R″), C(═O), B(R′)(R″), N(R′)(R″), or P(R′)(R″). R′ and R″ are the same as described herein.
In an embodiment, in Formula 1, i) X1, X2, and X4 may each be N, and X3 may be C, or ii) X2 and X4 may each be N, and X1 and X3 may each be C, but embodiments of the present disclosure are not limited thereto.
In one or more embodiments, X5 may be a single bond (for example, a covalent bond or a coordinate bond), O, or S, but embodiments of the present disclosure are not limited thereto.
In Formula 1, two bonds selected from a bond between X1 or X5 and M, a bond between X2 and M, a bond between X3 and M, and a bond between X4 and M may each be a covalent bond, and the other bonds selected from a bond between X1 or X5 and M, a bond between X2 and M, a bond between X3 and M, and a bond between X4 and M may each be a covalent bond may each be a coordinate bond. Thus, the organometallic compound represented by Formula 1 may be electrically neutral.
In an embodiment, in Formula 1, i) a bond between X1 or X5 and M and a bond between X3 and M may each be a covalent bond, and a bond between X2 and M and a bond between X4 and M may each be a coordinate bond, or ii) a bond between X1 or X5 and M and a bond between X2 and M may each be a covalent bond, and a bond between X3 and M and a bond between X4 and M may each be a coordinate bond.
CY1 to CY5 in Formula 1 may each independently be a C5-C30 carbocyclic group or a C1-C30 heterocyclic group.
For example, rings CY1 to CY5 may each independently be selected from a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a 1,2,3,4-tetrahydronaphthalene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an azafluorene group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group, a 5,6,7,8-tetrahydroquinoline group, an indazole group, a benzofluorene group, a benzocarbazole group, a naphthobenzofuran group, a naphthobenzothiophene group, and a naphtobenzosilole group.
In an embodiment, at least one of rings CY1 and CY2 may each independently be a condensed ring including at least one 5-membered ring condensed with at least one 6-membered ring, rings CY3 to CY5 may each independently be a 6-membered ring or a condensed ring including two or more 6-membered rings condensed with each other, the 5-membered ring may be selected from a cyclopentadiene group, a furan group, a thiophene group, a pyrrole group, a silole group, an oxazole group, an isoxazole group, an oxadiazole group, an isoxadiazole group, an oxatriazole group, an isoxatriazole group, a thiazole group, an isothiazole group, a thiadiazole group, an isothiadiazole group, a thiatriazole group, an isothiatriazole group, a pyrazole group, an imidazole group, a triazole group, a tetrazole group, an azasilole group, a diazasilole group, and a triazasilole group, and the 6-membered ring may be selected from a cyclohexane group, a cyclohexene group, a benzene group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, and a triazine group, but embodiments of the present disclosure are not limited thereto.
In Formula 1, T1 may be B, N, or P, T2 to T4 may each independently be selected from a single bond, a double bond, *—N(R7)—*′, *—B(R7)—*′, *—P(R7)—*′, *—C(R7)(R8)—*′, *—Si(R7)(R8)—*′, *—Ge(R7)(R8)—*′, *—Se—*′, *—C(═O)—*′, *—S(═O)—*′, *—S(═O)2—*′, *—C(R7)=*′, *═C(R7)—*′, *—C(R7)═C(R8)—*′, *—C(═S)—*′, and *—C≡C—*′, and * and *′ each indicate a binding site to a neighboring atom. R7 and R8 are the same as described herein, and R7 and R8 may optionally be linked via a single bond, a double bond, or a first linking group to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group.
The first linking group may be selected from *—N(R9)—*′, *—B(R9)—*′, *—P(R9)—*′, *—C(R9)(R10)—*′, *—Si(R9)(R10)—*′, *—Ge(R9)(R10)—*′, *—O—*′, *—C(═O)—*′, *—S(═O)—*—S(═O)2—*′, *—C(R9)=*′, *═C(R9)—*′, *—C(R9)═C(R10)—*′, *—C(═S)—*′, and *—C≡C—*′, R9 and R10 are the same as described in connection with R7, and * and *′ each indicate a binding site to a neighboring atom.
In an embodiment, T2 may be a single bond, but embodiments of the present disclosure are not limited thereto.
n3 and n4 in Formula 1 may each independently be 0 or 1, wherein, when n3 is 0, T3 does not exist and thus CY3 and CY5 are not linked to each other, and when n4 is 0, T4 does not exist and thus CY4 and CY5 are not linked to each other. The sum of n3 and n4 is 1 or 2, provided that a) when n3 is 0 and n4 is 1, X4 is N, b) when n3 is 1 and n4 is 0, X3 is N, and c) n3 and n4 are 1, at least one of X3 and X4 is N.
In an embodiment, in Formula 1,
R1 to R5, R′, R″, R7, and R8 in Formula 1 may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, —SF5, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C1-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(C21)(Q2), —Si(Q3)(Q4)(Q5), —B(Q6)(Q7), and —P(═O)(Q8)(Q9).
For example, R1 to R5, R′, R″, R7, and R8 may each independently be selected from:
In an embodiment, R1 to R5, R′, R″, R7, and R8 may each independently be selected from hydrogen, deuterium, —F, a cyano group, a nitro group, —SF5, —CH3, —CD3, —CD2H, —CDH2, —CF3, —CFH2, a C1-C10 alkoxy group, groups represented by Formulae 9-1 to 9-19, groups represented by Formulae 10-1 to 10-157, —N(Q1)(Q2), —Si(Q3)(Q4)(Q5), —B(Q6)(Q7), and —P(═O)(Q8)(Q9) (wherein Q1 to Q9 are the same as described herein), but embodiments of the present disclosure are not limited thereto:
In Formulae 9-1 to 9-19 and 10-1 to 10-157, “Ph” indicates a phenyl group, “TMS” indicates a trimethylsilyl group, and “*” indicates a binding site to a neighboring atom.
a1, a2, a3, a4, and a5 in Formula 1 respectively indicate the number of groups the number of groups R2, the number of groups R3, the number of groups R4, and the number of groups R5, and may each independently be an integer from 0 to 20 (for example, an integer from 0 to 4). When a1 is two or more, two or more groups R1 may be identical to or different from each other, when a2 is two or more, two or more groups R2 may be identical to or different from each other, when a3 is two or more, two or more groups R3 may be identical to or different from each other, when a4 is two or more, two or more groups R4 may be identical to or different from each other, and when a5 is two or more, two or more groups R5 may be identical to or different from each other.
In Formula 1, i) two of a plurality of neighboring groups R1 may optionally be linked to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, ii) two of a plurality of neighboring groups R2 may optionally be linked to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, iii) two of a plurality of neighboring groups R3 may optionally be linked to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, iv) two of a plurality of neighboring groups R4 may optionally be linked to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, v) two of a plurality of neighboring groups R5 may optionally be linked to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, and vi) two or more neighboring groups selected from R1 to R3 may optionally be linked to form a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group.
For example, i) a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, formed by linking two of a plurality of neighboring groups R1, ii) a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, formed by linking two of a plurality of neighboring groups R2, iii) a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, formed by linking two of a plurality of neighboring groups R3, iv) a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, formed by linking two of a plurality of neighboring groups R4, v) a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, formed by linking two of a plurality of neighboring groups R5, and vi) a substituted or unsubstituted C5-C30 carbocyclic group or a substituted or unsubstituted C1-C30 heterocyclic group, formed by linking two neighboring groups selected from R1 to R3, may each independently be selected from:
R10a is the same as described in connection with R1.
“Azabenzothiophene, azabenzofuran, azaindene, azaindole, azabenzosilole, azadibenzothiophene, azadibenzofuran, azafluorene, azacarbazole, and azadibenzosilole” as used herein mean hetero-rings that respectively have the same backbones as “benzothiophene, benzofuran, indene, indole, benzosilole, dibenzothiophene, dibenzofuran, fluorene, carbazole, and dibenzosilole”, provided that at least one of carbons forming rings thereof is substituted with nitrogen.
In an embodiment, in Formula 1,
may be represented by Formula A1-1, a moiety represented by
may be represented by Formula A2-1 or A2-2, and T2 may be a single bond;
be represented by Formula A1-2, a moiety represented by
may be represented by Formula A2-1 or A2-2, and T2 may be a single bond;
iii) X5 may be a single bond, a moiety represented by
may be represented by Formula A1-1, a moiety represented by
may be represented by Formula A2-1 or A2-2, and T2 may not be a single bond; or
iv) X5 may be a single bond, a moiety represented by
may be represented by Formula A1-1, a moiety represented by
may be represented by Formula A2-3, and T2 may be a single bond:
In Formulae A1-1, A1-2, and A2-1 to A2-3,
In one or more embodiments, a moiety represented by
in Formula 1 may be represented by one of Formulae A1-1(1) to A1-1(26) and A1-2(1) to A1-2(76), and
in Formula 1 may be represented by one of Formulae A2-1(1) to A2-1(21), A2-2(1) to A2-2(58), and A2-3(1) to A2-3(58):
In Formulae A1-1(1) to A1-1(26) and A1-2(1) to A1-2(76),
In Formulae A2-1(1) to A2-1(21), A2-2(1) to A2-2(58), and A2-3(1) to A2-3(58),
In one or more embodiments, in Formula 1,
may be represented by one of Formulae A1-1(1) to A1-1(26), a moiety represented by
may be represented by one of Formulae A2-1(1) to A2-1(21), and T2 may be a single bond;
may be represented by one of Formulae A1-2(1) to A1-2(76), a moiety represented by
may be represented by one of Formulae A2-1(1) to A2-1(21), and
iii) X5 may be a single bond, a moiety represented by
may be represented by one of Formulae A1-1(1) to A1-1(26), a moiety represented by
may be represented by one of Formulae A2-1(1) to A2-1(21), and T2 may not be a single bond; or
iv) X5 may be a single bond, a moiety represented by
may be represented by one of Formulae A1-1(1) to A1-1(26), a moiety represented by
may be represented by one of Formulae A2-3(1) to A2-3(58), and T2 may be a single bond.
In one or more embodiments, a moiety represented by
in Formula 1 may be represented by one of Formulae CY1-1 to CY1-39, and a moiety represented by
may be represented by one of Formulae CY2-1 to CY2-23:
In Formulae CY1-1 to CY1-39 and CY2-1 to CY2-23,
In one or more embodiments, a moiety represented by
in Formula 1 may be represented by Formula A3-1 or A3-3, and a moiety represented by
may be represented by Formula A4-1:
In Formulae A3-1, A3-3, and A4-1, X3, X4, ring CY3, ring CY4, R3, R4, a3, and a4 are the same as described herein, and Y5 to Y7 may each independently be N or C. In Formulae A3-1 and A3-3, * indicates a binding site to M in Formula 1, *′ indicates a binding site to T1 in Formula 1, and *″ indicates a binding site to ring CY3 in Formula 1. In Formula A4-1, * indicates a binding site to M in Formula 1, and *′ indicates a binding site to T1 in Formula 1.
In one or more embodiments, a moiety represented by
in Formula 1 may be represented by one of Formulae A3-1(1) to A3-1(21) and A3-3(1) to A3-3(58):
In Formulae A3-1(1) to A3-1(21) and A3-3(1) to A3-3(58),
In one or more embodiments, a moiety represented by
in Formula 1 may be represented by one of Formulae A4-1(1) to A4-1(44):
In Formulae A4-1(1) to A4-1(44),
In one or more embodiments, in Formula 1, a cyclometallated ring formed by M, X5, ring CY1, T2, and ring CY2 and a cyclometallated ring formed by M, ring CY4, T1, and ring CY3 may each be a 6-membered ring, and a cyclometallated ring formed by M, ring CY2, and ring CY3 may be a 5-membered ring.
In one or more embodiments, the organometallic compound may be represented by one of Formulae 1-1 to 1-3:
In Formulae 1-1 to 1-3,
In one or more embodiments, the organometallic compound may be represented by one of Formulae 1A-1 to 1A-3 and 1B:
In Formulae 1A-1 to 1A-3 and 1B,
The organometallic compound may be one of Compounds 1 to 160, but embodiments of the present disclosure are not limited thereto:
The sum of n3 and n4 in Formula 1 is 1 or 2, provided that a) when n3 is 0 and n4 is 1, X4 may be N, b) when n3 is 1 and n4 is 0, X3 may be N, and c) when n3 and n4 are each 1, at least one of X3 and X4 may be N. Accordingly, a four-coordinate ligand backbone in Formula 1 essentially includes a carboline group. Due to the carboline group, planarity of the organometallic compound represented by Formula 1 may be improved, and charge transfer characteristics may be improved. Thus, an electronic device, for example, an organic light-emitting device, which includes the organometallic compound, may have improved luminescence efficiency and/or lifespan characteristics.
In addition, since ring CY2 and ring CY3 in Formula 1 are linked via a single bond, rigidity of a molecular structure around a metal M in Formula 1 may be increased. Thus, full width at half maximum (FWHM) of a photoluminescence (PL) spectrum of the organometallic compound represented by Formula 1 and/or an electroluminescence (EL) spectrum of an electronic device (for example, an organic light-emitting device) including the organometallic compound represented by Formula 1 may be improved (for example, reduced). An electronic device, for example, an organic light-emitting device, which includes the organometallic compound, may have improved luminescence efficiency and/or lifespan characteristics.
For example, highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), and triplet (T1) energy levels of some of the Compounds illustrated above were evaluated by using a DFT method of a Gaussian program (structurally optimized at a level of B3LYP, 6-31 G(d,p)), and evaluation results thereof are shown in Table 1.
From Table 1, it is apparent that the organometallic compound represented by Formula 1 has such electrical characteristics that are suitable for use in an electronic device, for example, for use as a dopant for an organic light-emitting device.
Synthesis methods of the organometallic compound represented by Formula 1 may be recognizable by those of ordinary skill in the art by referring to Synthesis Examples provided below.
The organometallic compound represented by Formula 1 is suitable for use in an organic layer of an organic light-emitting device, for example, for use as a dopant in an emission layer of the organic layer.
Thus, another aspect provides an organic light-emitting device that includes:
The organic light-emitting device may have, due to the inclusion of an organic layer including the organometallic compound represented by Formula 1, a low driving voltage, high efficiency, high power, high quantum efficiency, a long lifespan, a low roll-off ratio, and excellent color purity.
The organometallic compound of Formula 1 may be used between a pair of electrodes of an organic light-emitting device. For example, the organometallic compound represented by Formula 1 may be included in the emission layer. In this embodiment, the organometallic compound may act as a dopant, and the emission layer may further include a host (that is, an amount of the organometallic compound represented by Formula 1 is smaller than an amount of the host).
The expression “(an organic layer) includes at least one of organometallic compounds” as used herein may include an embodiment in which “(an organic layer) includes identical organometallic compounds represented by Formula 1” and an embodiment in which “(an organic layer) includes two or more different organometallic compounds represented by Formula 1.”
For example, the organic layer may include, as the organometallic compound, only Compound 1. In this embodiment, Compound 1 may be included in an emission layer of the organic light-emitting device. In one or more embodiments, the organic layer may include, as the organometallic compound, Compound 1 and Compound 2. In this embodiment, Compound 1 and Compound 2 may be included in an identical layer (for example, Compound 1 and Compound 2 all may be included in an emission layer).
The first electrode may be an anode, which is a hole injection electrode, and the second electrode may be a cathode, which is an electron injection electrode; or the first electrode may be a cathode, which is an electron injection electrode, and the second electrode may be an anode, which is a hole injection electrode.
In an embodiment, in the organic light-emitting device, the first electrode is an anode, and the second electrode is a cathode, and the organic layer further includes a hole transport region disposed between the first electrode and the emission layer and an electron transport region disposed between the emission layer and the second electrode, wherein the hole transport region includes a hole injection layer, a hole transport layer, an electron blocking layer, or any combination thereof, and wherein the electron transport region includes a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.
The term “organic layer” as used herein refers to a single layer and/or a plurality of layers between the first electrode and the second electrode of the organic light-emitting device. The “organic layer” may include, in addition to an organic compound, an organometallic complex including metal.
The FIG. is a schematic view of an organic light-emitting device 10 according to an embodiment. Hereinafter, the structure of an organic light-emitting device according to an embodiment and a method of manufacturing an organic light-emitting device according to an embodiment will be described in connection with the FIGURE. The organic light-emitting device 10 includes a first electrode 11, an organic layer 15, and a second electrode 19, which are sequentially stacked.
A substrate may be additionally disposed under the first electrode 11 or above the second electrode 19. For use as the substrate, any substrate that is used in general organic light-emitting devices may be used, and the substrate may be a glass substrate or a transparent plastic substrate, each having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.
The first electrode 11 may be formed by depositing or sputtering a material for forming the first electrode 11 on the substrate. The first electrode 11 may be an anode. The material for forming the first electrode 11 may be selected from materials with a high work function to facilitate hole injection. The first electrode 11 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. The material for forming the first electrode may be, for example, indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), and zinc oxide (ZnO). In one or more embodiments, magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag) may be used as the material for forming the first electrode.
The first electrode 11 may have a single-layered structure or a multi-layered structure including two or more layers. For example, the first electrode 11 may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode 110 is not limited thereto.
The organic layer 15 is disposed on the first electrode 11.
The organic layer 15 may include a hole transport region, an emission layer, and an electron transport region.
The hole transport region may be disposed between the first electrode 11 and the emission layer.
The hole transport region may include a hole injection layer, a hole transport layer, an electron blocking layer, a buffer layer, or any combination thereof.
The hole transport region may include only either a hole injection layer or a hole transport layer. In one or more embodiments, the hole transport region may have a hole injection layer/hole transport layer structure or a hole injection layer/hole transport layer/electron blocking layer structure, which are sequentially stacked in this stated order from the first electrode 11.
When the hole transport region includes a hole injection layer, a hole injection layer may be formed on the first electrode 11 by using one or more suitable methods selected from vacuum deposition, spin coating, casting, or Langmuir-Blodgett (LB) deposition.
When a hole injection layer is formed by vacuum deposition, the deposition conditions may vary according to a compound that is used to form the hole injection layer, and the structure and thermal characteristics of the hole injection layer. For example, the deposition conditions may include a deposition temperature of about 100° C. to about 500° C., a vacuum pressure of about 10−8 torr to about 10−3 torr, and a deposition rate of about 0.01 Angstroms per second (Å/sec) to about 100 Å/sec. However, the deposition conditions are not limited thereto.
When the hole injection layer is formed using spin coating, coating conditions may vary according to the material used to form the hole injection layer, and the structure and thermal properties of the hole injection layer. For example, a coating speed may be from about 2,000 revolutions per minute (rpm) to about 5,000 rpm, and a temperature at which a heat treatment is performed to remove a solvent after coating may be from about 80° C. to about 200° C. However, the coating conditions are not limited thereto.
Conditions for forming a hole transport layer and an electron blocking layer may be understood by referring to conditions for forming the hole injection layer.
The hole transport region may include at least one selected from m-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzene sulfonic acid (PANI/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrene sulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrene sulfonate) (PANI/PSS), a compound represented by Formula 201 below, and a compound represented by Formula 202 below:
Ar101 and Ar102 in Formula 201 may each independently be selected from:
a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an acenaphthylene group, a fluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, and a pentacenylene group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C10 cycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.
In Formula 201, xa and xb may each independently be an integer from 0 to 5, or may each independently be 0, 1, or 2. For example, xa is 1 and xb is 0, but xa and xb are not limited thereto.
R101 to R108, R111 to R119, and R121 to R124 in Formula 201 and 202 may each independently be selected from:
R109 in Formula 201 may be selected from:
In an embodiment, the compound represented by Formula 201 may be represented by Formula 201A, but embodiments of the present disclosure are not limited thereto:
R101, R111, R112, and R109 in Formula 201A may be understood by referring to the description provided herein.
For example, the compound represented by Formula 201, and the compound represented by Formula 202 may include compounds HT1 to HT20 illustrated below, but are not limited thereto.
A thickness of the hole transport region may be in a range of about 100 Angstroms (Å) to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When the hole transport region includes at least one of a hole injection layer and a hole transport layer, the thickness of the hole injection layer may be in a range of about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å, and the thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example, about 100 Å to about 1,500 Å. While not wishing to be bound by theory, it is understood that when the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage.
The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region.
The charge-generation material may be, for example, a p-dopant. The p-dopant may be one selected from a quinone derivative, a metal oxide, and a cyano group-containing compound, but embodiments of the present disclosure are not limited thereto. Non-limiting examples of the p-dopant are a quinone derivative, such as tetracyanoquinonedimethane (TCNQ) or 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (F4-TCNQ); a metal oxide, such as a tungsten oxide or a molybdenium oxide; and a cyano group-containing compound, such as Compound HT-D1 below, but are not limited thereto:
The hole transport region may include a buffer layer.
Also, the buffer layer may compensate for an optical resonance distance according to a wavelength of light emitted from the emission layer, and thus, efficiency of a formed organic light-emitting device may be improved.
Then, an emission layer may be formed on the hole transport region by vacuum deposition, spin coating, casting, LB deposition, or the like. When the emission layer is formed by vacuum deposition or spin coating, the deposition or coating conditions may be similar to those applied in forming the hole injection layer although the deposition or coating conditions may vary depending on a compound that is used to form the emission layer.
Meanwhile, when the hole transport region includes an electron blocking layer, a material for the electron blocking layer may be selected from materials for the hole transport region described above and materials for a host to be explained later. However, the material for the electron blocking layer is not limited thereto. For example, when the hole transport region includes an electron blocking layer, a material for the electron blocking layer may be mCP, which will be explained later.
The emission layer may include a host and a dopant, and the dopant may include the organometallic compound represented by Formula 1.
The host may include at least one selected from TPBi, TBADN, ADN (also referred to as “DNA”), CBP, CDBP, TCP, mCP, Compound H50, and Compound H51:
In one or more embodiments, the host may further include a compound represented by Formula 301 below:
Ar111 and Ar112 in Formula 301 may each independently be selected from:
Ar113 to Ar116 in Formula 301 may each independently be selected from:
g, h, i, and j in Formula 301 may each independently be an integer from 0 to 4, and may each independently be, for example, 0, 1, or 2.
Ar113 to Ar116 in Formula 301 may each independently be selected from:
In one or more embodiments, the host may include a compound represented by Formula 302 below:
Ar122 to Ar125 in Formula 302 are the same as described in detail in connection with Ar113 in Formula 301.
Ar126 and Ar127 in Formula 302 may each independently be a C1-C10 alkyl group (for example, a methyl group, an ethyl group, or a propyl group).
k and l in Formula 302 may each independently be an integer from 0 to 4. For example, k and l may be 0, 1, or 2.
When the organic light-emitting device is a full-color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and a blue emission layer. In one or more embodiments, due to a stacked structure including a red emission layer, a green emission layer, and/or a blue emission layer, the emission layer may emit white light.
When the emission layer includes a host and a dopant, an amount of the dopant may be in a range of about 0.01 parts by weight to about 15 parts by weight based on 100 parts by weight of the host, but embodiments of the present disclosure are not limited thereto.
A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within this range, excellent light-emission characteristics may be obtained without a substantial increase in driving voltage.
Then, an electron transport region may be disposed on the emission layer.
The electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.
For example, the electron transport region may have a hole blocking layer/electron transport layer/electron injection layer structure or an electron transport layer/electron injection layer structure, but the structure of the electron transport region is not limited thereto. The electron transport layer may have a single-layered structure or a multi-layered structure including two or more different materials.
Conditions for forming the hole blocking layer, the electron transport layer, and the electron injection layer which constitute the electron transport region may be understood by referring to the conditions for forming the hole injection layer.
When the electron transport region includes a hole blocking layer, the hole blocking layer may include, for example, at least one of BCP, Bphen, and BAlq but embodiments of the present disclosure are not limited thereto:
A thickness of the hole blocking layer may be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. While not wishing to be bound by theory, it is understood that when the thickness of the hole blocking layer is within these ranges, the hole blocking layer may have improved hole blocking ability without a substantial increase in driving voltage.
The electron transport layer may further include at least one selected from BCP, Bphen, Alq3, BAlq, TAZ, and NTAZ:
In one or more embodiments, the electron transport layer may include at least one of ET1 and ET25, but are not limited thereto:
A thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. While not wishing to be bound by theory, it is understood that when the thickness of the electron transport layer is within the range described above, the electron transport layer may have satisfactory electron transport characteristics without a substantial increase in driving voltage.
Also, the electron transport layer may further include, in addition to the materials described above, a metal-containing material.
The metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) or ET-D2:
The electron transport region may include an electron injection layer that promotes flow of electrons from the second electrode 19 thereinto.
The electron injection layer may include at least one selected from LiF, NaCl, CsF, Li2O, and BaO.
A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å. While not wishing to be bound by theory, it is understood that when the thickness of the electron injection layer is within the range described above, the electron injection layer may have satisfactory electron injection characteristics without a substantial increase in driving voltage.
The second electrode 19 is disposed on the organic layer 15. The second electrode 19 may be a cathode. A material for forming the second electrode 19 may be selected from metal, an alloy, an electrically conductive compound, and a combination thereof, which have a relatively low work function. For example, lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag) may be used as a material for forming the second electrode 19. In one or more embodiments, to manufacture a top-emission type light-emitting device, a transmissive electrode formed using ITO or IZO may be used as the second electrode 19.
Hereinbefore, the organic light-emitting device has been described with reference to the FIGURE, but embodiments of the present disclosure are not limited thereto.
Another aspect of the present disclosure provides a diagnostic composition including at least one organometallic compound represented by Formula 1.
The organometallic compound represented by Formula 1 provides high luminescent efficiency. Accordingly, a diagnostic composition including the organometallic compound may have high diagnostic efficiency.
The diagnostic composition may be used in various applications including a diagnosis kit, a diagnosis reagent, a biosensor, and a biomarker.
The term “C1-C60 alkyl group” as used herein refers to a linear or branched saturated aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and non-limiting examples thereof include a methyl group, an ethyl group, a propyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group. The term “C1-C60 alkylene group” as used herein refers to a divalent group having the same structure as the C1-C60 alkyl group.
The term “C1-C60 alkoxy group” as used herein refers to a monovalent group represented by —OA101 (wherein A101 is the C1-C60 alkyl group), and non-limiting examples thereof include a methoxy group, an ethoxy group, and an iso-propyloxy group.
The term “C2-C60 alkenyl group” as used herein refers to a hydrocarbon group formed by including at least one carbon-carbon double bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof include an ethenyl group, a propenyl group, and a butenyl group. The term “C2-C60 alkenylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkenyl group.
The term “C2-C60 alkynyl group” as used herein refers to a hydrocarbon group formed by including at least one carbon-carbon triple bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof include an ethynyl group, and a propynyl group. The term “C2-C60 alkynylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkynyl group.
The term “C3-C10 cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, and non-limiting examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term “C3-C10 cycloalkylene group” as used herein refers to a divalent group having the same structure as the C3-C10 cycloalkyl group.
The term “C1-C10 heterocycloalkyl group” as used herein refers to a monovalent saturated monocyclic group having at least one heteroatom selected from N, O, P, Si and S as a ring-forming atom and 1 to 10 carbon atoms, and non-limiting examples thereof include a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C1-C10 heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C1-C10 heterocycloalkyl group.
The term “C3-C10 cycloalkenyl group” as used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring thereof and that has no aromaticity, and non-limiting examples thereof include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C3-C10 cycloalkenylene group” as used herein refers to a divalent group having the same structure as the C3-C10 cycloalkenyl group.
The term “C1-C10 heterocycloalkenyl group” as used herein refers to a monovalent monocyclic group that has at least one heteroatom selected from N, O, P, Si, and S as a ring-forming atom, 1 to 10 carbon atoms, and at least one carbon-carbon double bond in its ring. Examples of the C1-C10 heterocycloalkenyl group are a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C1-C10 heterocycloalkenylene group” as used herein refers to a divalent group having the same structure as the C1-C10 heterocycloalkenyl group.
The term “C6-C60 aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and the term “C6-C60 arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Non-limiting examples of the C6-C60 aryl group include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C6-C60 aryl group and the C6-C60 arylene group each include two or more rings, the rings may be fused to each other.
The term “C1-C60 heteroaryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, P, Si, and S as a ring-forming atom, and 1 to 60 carbon atoms. The term “C1-C60 heteroarylene group” as used herein refers to a divalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, P, and S as a ring-forming atom, and 1 to 60 carbon atoms. Non-limiting examples of the C1-C60 heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each include two or more rings, the rings may be fused to each other.
The term “C6-C60 aryloxy group” as used herein indicates —OA102 (wherein A102 is the C6-C60 aryl group), and a C6-C60 arylthio group as used herein indicates —SA103 (wherein A103 is the C6-C60 aryl group).
The term “monovalent non-aromatic condensed polycyclic group” as used herein refers to a monovalent group (for example, having 8 to 60 carbon atoms) having two or more rings condensed to each other, only carbon atoms as ring-forming atoms, and having no aromaticity in its entire molecular structure. Examples of the monovalent non-aromatic condensed polycyclic group include a fluorenyl group. The term “divalent non-aromatic condensed polycyclic group,” as used herein, refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.
The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group (for example, having 2 to 60 carbon atoms) having two or more rings condensed to each other, a heteroatom selected from N, O, P, Si, and S, other than carbon atoms, as a ring-forming atom, and having no aromaticity in its entire molecular structure. Non-limiting examples of the monovalent non-aromatic condensed heteropolycyclic group include a carbazolyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group.
The term “C5-C30 carbocyclic group” as used herein refers to a saturated or unsaturated cyclic group having, as a ring-forming atom, 5 to 30 carbon atoms only. The C5-C30 carbocyclic group may be a monocyclic group or a polycyclic group.
The term “C1-C30 heterocyclic group” as used herein refers to a saturated or unsaturated cyclic group having, as a ring-forming atom, at least one heteroatom selected from N, O, Si, P, and S other than 1 to 30 carbon atoms. The C1-C30 heterocyclic group may be a monocyclic group or a polycyclic group.
At least one substituent of the substituted C5-C30 carbocyclic group, the substituted C2-C30 heterocyclic group, the substituted C1-C60 alkyl group, the substituted C2-C60 alkenyl group, the substituted C2-C60 alkynyl group, the substituted C1-C60 alkoxy group, the substituted C3-C10 cycloalkyl group, the substituted C1-C10 heterocycloalkyl group, the substituted C3-C10 cycloalkenyl group, the substituted C1-C10 heterocycloalkenyl group, the substituted C6-C60 aryl group, the substituted C6-C60 aryloxy group, the substituted C6-C60 arylthio group, the substituted C1-C60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from:
When a group containing a specified number of carbon atoms is substituted with any of the groups listed in the preceding paragraph, the number of carbon atoms in the resulting “substituted” group is defined as the sum of the carbon atoms contained in the original (unsubstituted) group and the carbon atoms (if any) contained in the substituent. For example, when the term “substituted C1-C30 alkyl” refers to a C1-C30 alkyl group substituted with C6-C30 aryl group, the total number of carbon atoms in the resulting aryl substituted alkyl group is C7-C60.
Hereinafter, a compound and an organic light-emitting device according to embodiments are described in detail with reference to Synthesis Examples and Examples. However, the organic light-emitting device is not limited thereto. The wording “B was used instead of A” used in describing Synthesis Examples means that an amount of A used was identical to an amount of B used, in terms of a molar equivalent.
Synthesis of Intermediate P2
2.2 grams, g (6.8 millimoles, mmol) of Compound P3, 3.4 g (13.5 mmol) of 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane), 0.50 g (0.7 mmol) of PdCl2(dppf), 1.99 g (20.3 mmol) of potassium acetate, and 150 milliliters (mL) of toluene were mixed and stirred under reflux for 18 hours. After the reaction had been complete, the reaction product was cooled to room temperature. The organic layer was extracted therefrom with methylene chloride (MC), dried with anhydrous magnesium sulfate (MgSO4), and filtered to obtain a filtrate. The filtrate was then distilled under reduced pressure. The residue obtained therefrom was purified by column chromatography with ethyl acetate (EA):hexane as an eluent to obtain 2.23 g (89%) of Intermediate P2.
Synthesis of Ligand 3L
1.7 g (6.3 mmol) of material A, 2.23 g (6.0 mmol) of Intermediate P2, 0.5 g (0.4 mmol) of Pd(PPh3)4, 2.5 g (18.1 mmol) of K2CO3, 60 mL of tetrahydrofuran (THF), and 20 mL of distilled water were mixed and stirred under reflux for 12 hours. After the resultant mixture was cooled to room temperature, the organic layer was extracted therefrom with MC, dried with anhydrous magnesium sulfate (MgSO4), and filtered to obtain a filtrate. The filtrate was then distilled under reduced pressure. The residue obtained therefrom was purified by column chromatography with MC:hexane as an eluent to obtain 1.8 g (64%) of Ligand 3L.
Synthesis of Compound 3
0.9 g (1.9 mmol) of Ligand 3L, 1.0 g (2.18 mmol) of K2PtC14, and 50 mL of acetic acid were mixed and stirred under reflux for 18 hours. After the reaction had been complete, the reaction product was cooled. The solid obtained therefrom was filtered, and purified by column chromatography with MC:hexane as an eluent to obtain 0.4 g (32%) of Compound 3. The obtained product was identified by Mass and HPLC analysis.
HRMS (MALDI) calcd for C32H25N3OPt: m/z 662.1645. Found: 662.1650.
Synthesis of Ligand 86L
2.4 g (4.7 mmol) of material B, 1.6 g (4.5 mmol) of Intermediate P2, 0.4 g (0.3 mmol) of Pd(PPh3)4, 1.8 g (13.3 mmol) of K2CO3, 90 mL of THF, and 30 mL of distilled water were mixed and stirred under reflux for 12 hours. After the resultant mixture was cooled to room temperature, the organic layer was extracted therefrom with MC, dried with anhydrous magnesium sulfate (MgSO4), and filtered to obtain a filtrate. The filtrate was then distilled under reduced pressure. The residue obtained therefrom was purified by column chromatography with MC:hexane as an eluent to obtain 2.3 g (77%) of Ligand 86L.
Synthesis of Compound 86
2.6 g (3.9 mmol) of Ligand 86L and 2.0 g (4.3 mmol) of K2PtCl4 were mixed with 100 mL of acetic acid and then stirred under reflux for 18 hours. After the reaction had been complete, the reaction product was cooled. The solid obtained therefrom was filtered, and purified by column chromatography with MC:hexane as an eluent to obtain 0.9 g (32%) of Compound 86. The obtained product was identified by Mass and HPLC analysis.
HRMS (MALDI) calcd for C48H40N4Pt: m/z 867.2901. Found: 867.2904.
Synthesis of Ligand AL
1.7 g (6.7 mmol) of material A, 2.4 g (6.4 mmol) of material C, 0.5 g (0.5 mmol) of Pd(PPh3)4, 2.6 g (19.1 mmol) of K2CO3, 90 mL of THF, and 30 mL of distilled water were mixed and stirred under reflux for 12 hours. After the resultant mixture was cooled to room temperature, the organic layer was extracted therefrom with MC, dried with anhydrous magnesium sulfate (MgSO4), and filtered to obtain a filtrate. The filtrate was then distilled under reduced pressure. The residue obtained therefrom was purified by column chromatography with MC:hexane as an eluent to obtain 2.1 g (70%) of Ligand AL.
Synthesis of Compound A
1.4 g (3.0 mmol) of Ligand AL and 1.6 g (3.3 mmol) of K2PtCl4 were mixed with 100 mL of acetic acid and stirred under reflux for 18 hours. After the reaction had been complete, the reaction product was cooled. The solid obtained therefrom was filtered, and purified by column chromatography with MC:hexane as an eluent to obtain 0.7 g (35%) of Compound A. The obtained product was identified by Mass and HPLC analysis.
HRMS (MALDI) calcd for C32H27N3OPt: m/z 664.1802. Found: 664.1798.
As an anode, a glass substrate, on which ITO/Ag/ITO were respectively deposited to thicknesses of 70 Å/1,000 Å/70 Å, was cut to a size of 50 mm×50 mm×0.5 mm (mm=millimeter), sonicated with iso-propyl alcohol and pure water each for 5 minutes, and then cleaned by exposure to ultraviolet rays and ozone for 30 minutes. Then, the resultant glass substrate was provided to a vacuum deposition apparatus.
2-TNATA was deposited on the anode to form a hole injection layer having a thickness of 600 Å, and 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB) was deposited on the hole injection layer to form a hole transport layer having a thickness of 1,350 Å.
CBP (host) and Compound 3 (dopant) were co-deposited on the hole transport layer at a weight ratio of 90:10 to form an emission layer having a thickness of 400 Å, and BCP was deposited on the emission layer to form a hole blocking layer having a thickness of 50 Å. Then, Alq3 was deposited on the hole blocking layer to form an electron transport layer having a thickness of 350 Å, LiF was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, and MgAg was deposited on the electron injection layer at a weight ratio of 90:10 to form a cathode having a thickness of 120 Å, thereby completing the manufacture of an organic light-emitting device (emitting red light) having a structure of ITO/Ag/ITO/2-TNATA (600 Å) /NPB (1,350 Å)/CBP+Compound 3 (10 wt %) (400 Å)/BCP (50 Å)/Alq3 (350 Å)/LiF (10 Å)/MgAg (120 Å).
Organic light-emitting devices were manufactured in the same manner as in Example 1, except that Compounds shown in Table 2 were used instead of Compound 3 as a dopant in forming an emission layer.
The driving voltage, maximum photoluminescence quantum yield, and lifespan (T97) of the organic light-emitting devices manufactured according to Examples 1 and 2 and Comparative Example A were evaluated, and evaluation results thereof are shown in Table 2. This evaluation was performed by using a current-voltage meter (Keithley 2400) and a luminance meter (Minolta Cs-1000A). The lifespan (T97) indicates an amount of time (hr) that lapsed when luminance was 97% of initial luminance (100%). The maximum photoluminescence quantum yield and the lifespan (T97) are relative values with respect to those of the organic light-emitting device of Example 1.
Referring to Table 2, it is confirmed that the organic light-emitting devices of Examples 1 and 2 have improved characteristics, as compared with those of the organic light-emitting device of Comparative Example A.
Since the organometallic compounds have excellent electrical characteristics and thermal stability, organic light-emitting devices including such organometallic compounds may have excellent driving voltage, efficiency, power, color purity, and lifespan characteristics. Also, due to excellent phosphorescent luminescence characteristics, such organometallic compounds may provide a diagnostic composition having high diagnostic efficiency.
It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments.
While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2017-0076822 | Jun 2017 | KR | national |
