Patent Application
20230354634
This application claims priority to and the benefit of Korean Patent Application No. 10-2022-0053707 filed in the Korean Intellectual Property Office on Apr. 29, 2022, the entire contents of which are incorporated herein by reference.
Embodiments relate to an organic optoelectronic device and a display device.
An organic optoelectronic device (e.g., organic optoelectronic diode) is a device that converts electrical energy into photoenergy, and vice versa.
An organic optoelectronic device may be classified as follows in accordance with its driving principles. One is a photoelectric device where excitons generated by photoenergy are separated into electrons and holes and the electrons and holes are transferred to different electrodes respectively and electrical energy is generated, and the other is a light emitting device to generate photoenergy from electrical energy by supplying a voltage or a current to electrodes.
Examples of the organic optoelectronic device include an organic photoelectric device, an organic light emitting diode, an organic solar cell, and an organic photo conductor drum.
Among them, the organic light emitting diode (OLED) has recently drawn attention due to an increase in demand for flat panel displays. The organic light emitting diode converts electrical energy into light, and the performance of organic light emitting diode is greatly influenced by the organic materials disposed between electrodes.
The embodiments may be realized by providing an organic optoelectronic device including an anode and a cathode facing each other, a light emitting layer between the anode and the cathode, a hole transport layer between the anode and the light emitting layer, and a hole transport auxiliary layer between the light emitting layer and the hole transport layer, wherein the light emitting layer includes a first compound represented by Chemical Formula 1 and a second compound represented by Chemical Formula 2 or represented by a combination of Chemical Formula 3 and Chemical Formula 4, and the hole transport auxiliary layer includes a third compound represented by Chemical Formula 5:
in Chemical Formula 1, Z1 to Z3 are each independently N or CRa, at least two of Z1 to Z3 are N, L1 is a single bond or a substituted or unsubstituted C6 to C18 arylene group, Ra and R1 to R3 are each independently hydrogen, deuterium, a cyano group, a substituted or unsubstituted C1 to C20 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, Ar1 and Ar2 are each independently a substituted or unsubstituted C6 to C18 aryl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group, m1 and m2 are each independently an integer of 1 to 4, and m3 is an integer of 1 to 3;
in Chemical Formula 2, Ar3 and Ar4 are each independently a substituted or unsubstituted C6 to C20 aryl group or a substituted or unsubstituted C2 to C30 heterocyclic group, L2 and L3 are each independently a single bond or a substituted or unsubstituted C6 to C20 arylene group, R4 to R14 are each independently hydrogen, deuterium, a cyano group, a halogen, a substituted or unsubstituted amine group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heterocyclic group, m4 and m5 are each independently an integer of 1 to 3, m6 is an integer of 1 to 4, and n1 is an integer of 0 to 2;
in Chemical Formula 3 and Chemical Formula 4, Ar5 and Ar6 are each independently a substituted or unsubstituted C6 to C20 aryl group or a substituted or unsubstituted C2 to C30 heterocyclic group, two adjacent ones of a1* to a4* in Chemical Formula 3 are linking carbons linked at * of Chemical Formula 4, the remaining two of a1* to a4* of Chemical Formula 3, not linked at * of Chemical Formula 4, are C-La-Rb, La, L4, and L5 are each independently a single bond or a substituted or unsubstituted C6 to C20 arylene group, and Rb and R15 to R22 are each independently hydrogen, deuterium, a cyano group, a halogen, a substituted or unsubstituted amine group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heterocyclic group;
in Chemical Formula 5, X1 is C or Si, R23 to R26 are each independently hydrogen, deuterium, a cyano group, a halogen, a substituted or unsubstituted amine group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heterocyclic group, R27 and R28 are each independently a substituted or unsubstituted C1 to C30 alkyl group or a substituted or unsubstituted C6 to C30 aryl group, AC is a substituted or unsubstituted C6 to C30 aryl group, Ar8 is a substituted or unsubstituted C6 to C30 aryl group or a substituted or unsubstituted dibenzosilolyl group, L6 to L8 are each independently a single bond or a substituted or unsubstituted C6 to C20 arylene group, m7, m8, and m10 are each independently an integer of 1 to 4, and m9 is an integer of 1 to 3.
The embodiments may be realized by providing a display device including the organic photoelectronic device according to an embodiment.
Features will be apparent to those of skill in the art by describing in detail exemplary embodiments with reference to the attached drawing in which:
the
Example embodiments will now be described more fully hereinafter with reference to the accompanying drawing; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art.
In the drawing FIGURE, the dimensions of layers and regions may be exaggerated for clarity of illustration. It will also be understood that when a layer or element is referred to as being “on” another layer or element, it can be directly on the other layer or element, or intervening layers may also be present. In addition, it will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to like elements throughout.
As used herein, when a definition is not otherwise provided, “substituted” refers to replacement of at least one hydrogen of a substituent or a compound by deuterium, a halogen, a hydroxyl group, an amino group, a substituted or unsubstituted C1 to C30 amine group, a nitro group, a substituted or unsubstituted C1 to C40 silyl group, a C1 to C30 alkyl group, a C1 to C10 alkylsilyl group, a C6 to C30 arylsilyl group, a C3 to C30 cycloalkyl group, a C3 to C30 heterocycloalkyl group, a C6 to C30 aryl group, a C2 to C30 heteroaryl group, a C1 to C20 alkoxy group, a C1 to C10 trifluoroalkyl group, a cyano group, or a combination thereof.
In one example, “substituted” refers to replacement of at least one hydrogen of a substituent or a compound by deuterium, a C1 to C30 alkyl group, a C1 to C10 alkylsilyl group, a C6 to C30 arylsilyl group, a C3 to C30 cycloalkyl group, a C3 to C30 heterocycloalkyl group, a C6 to C30 aryl group, a C2 to C30 heteroaryl group, or a cyano group. In addition, in specific examples, “substituted” refers to replacement of at least one hydrogen of a substituent or a compound by deuterium, a C1 to C20 alkyl group, a C6 to C30 aryl group, or a cyano group. In addition, in specific examples of the present disclosure, “substituted” refers to replacement of at least one hydrogen of a substituent or a compound by deuterium, a C1 to C5 alkyl group, a C6 to C18 aryl group, or a cyano group. In addition, in specific examples of the present disclosure, “substituted” refers to replacement of at least one hydrogen of a substituent or a compound by deuterium, a cyano group, a methyl group, an ethyl group, a propyl group, a butyl group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group.
As used herein, “unsubstituted” refers to non-replacement of a hydrogen atom by another substituent and remaining of the hydrogen atom.
As used herein, “hydrogen substitution (—H)” may include deuterium substitution (-D) or tritium substitution (-T). For example, any hydrogen in any compound described herein may be protium, deuterium, or tritium (e.g., based on natural or artificial substitution).
As used herein, when a definition is not otherwise provided, “hetero” refers to one including one to three heteroatoms selected from N, O, S, P, and Si, and remaining carbons in one functional group.
As used herein, “aryl group” refers to a group including at least one hydrocarbon aromatic moiety, and may include a group in which all elements of the hydrocarbon aromatic moiety have p-orbitals which form conjugation, for example a phenyl group, a naphthyl group, and the like, a group in which two or more hydrocarbon aromatic moieties may be linked by a sigma bond, for example a biphenyl group, a terphenyl group, a quarterphenyl group, and the like, and a group in which two or more hydrocarbon aromatic moieties are fused directly or indirectly to provide a non-aromatic fused ring, for example, a fluorenyl group, and the like.
The aryl group may include a monocyclic, polycyclic or fused ring polycyclic (i.e., rings sharing adjacent pairs of carbon atoms) functional group.
As used herein, “heterocyclic group” is a generic concept of a heteroaryl group, and may include at least one heteroatom selected from N, O, S, P, and Si instead of carbon (C) in a cyclic compound such as aryl group, a cycloalkyl group, a fused ring thereof, or a combination thereof. When the heterocyclic group is a fused ring, the entire ring or each ring of the heterocyclic group may include one or more heteroatoms.
For example, “heteroaryl group” refers to an aryl group including at least one heteroatom selected from N, O, S, P, and Si. Two or more heteroaryl groups are linked by a sigma bond directly, or when the heteroaryl group includes two or more rings, the two or more rings may be fused. When the heteroaryl group is a fused ring, each ring may include one to three heteroatoms.
More specifically, the substituted or unsubstituted C6 to C30 aryl group may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted phenanthrenyl group, a substituted or unsubstituted naphthacenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted p-terphenyl group, a substituted or unsubstituted m-terphenyl group, a substituted or unsubstituted o-terphenyl group, a substituted or unsubstituted chrysenyl group, a substituted or unsubstituted triphenylene group, a substituted or unsubstituted perylenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted indenyl group, or a combination thereof, but is not limited thereto.
More specifically, the substituted or unsubstituted C2 to C30 heterocyclic group may be a substituted or unsubstituted furanyl group, a substituted or unsubstituted thiophenyl group, a substituted or unsubstituted pyrrolyl group, a substituted or unsubstituted pyrazolyl group, a substituted or unsubstituted imidazolyl group, a substituted or unsubstituted triazolyl group, a substituted or unsubstituted oxazolyl group, a substituted or unsubstituted thiazolyl group, a substituted or unsubstituted oxadiazolyl group, a substituted or unsubstituted thiadiazolyl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted pyrimidinyl group, a substituted or unsubstituted pyrazinyl group, a substituted or unsubstituted triazinyl group, a substituted or unsubstituted benzofuranyl group, a substituted or unsubstituted benzothiophenyl group, a substituted or unsubstituted benzimidazolyl group, a substituted or unsubstituted indolyl group, a substituted or unsubstituted quinolinyl group, a substituted or unsubstituted isoquinolinyl group, a substituted or unsubstituted quinazolinyl group, a substituted or unsubstituted quinoxalinyl group, a substituted or unsubstituted naphthyridinyl group, a substituted or unsubstituted benzoxazinyl group, a substituted or unsubstituted benzothiazinyl group, a substituted or unsubstituted acridinyl group, a substituted or unsubstituted phenazinyl group, a substituted or unsubstituted phenothiazinyl group, a substituted or unsubstituted phenoxazinyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group, or a combination thereof, but is not limited thereto.
In the present specification, hole characteristics refer to an ability to donate an electron to form a hole when an electric field is applied and that a hole formed in the anode may be easily injected into the light emitting layer and transported in the light emitting layer due to conductive characteristics according to the highest occupied molecular orbital (HOMO) level.
In addition, electron characteristics refer to an ability to accept an electron when an electric field is applied and that electron formed in the cathode may be easily injected into the light emitting layer and transported in the light emitting layer due to conductive characteristics according to the lowest unoccupied molecular orbital (LUMO) level.
Hereinafter, an organic optoelectronic device according to an embodiment will be described.
The organic optoelectronic device may be a suitable device to convert electrical energy into photoenergy and vice versa, and may be, e.g., an organic photoelectric device, an organic light emitting diode, an organic solar cell, or an organic photo conductor drum.
Herein, an organic light emitting diode as one example of an organic optoelectronic device is described, or it may be applied to other organic optoelectronic devices in the same way.
Referring to
The anode 10 may be made of a conductor having a large work function to help hole injection, and may be, e.g., a metal, a metal oxide, or a conductive polymer. The anode 10 may be, for example, a metal such as nickel, platinum, vanadium, chromium, copper, zinc, gold, or the like or an alloy thereof; a metal oxide such as zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), or the like; a combination of a metal and an oxide such as ZnO and Al or SnO2 and Sb; a conductive polymer such as poly(3-methylthiophene), poly(3,4-(ethylene-1,2-dioxy)thiophene) (PEDOT), polypyrrole, or polyaniline. As used herein, the term “or” is not an exclusive term, e.g., “A or B” would include A, B, or A and B
The cathode 20 may be made of a conductor having a small work function to help electron injection, and may be, e.g., a metal, a metal oxide, or a conductive polymer. The cathode 20 may be, e.g., a metal such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, lead, cesium, barium, or the like, or an alloy thereof; or a multi-layer structure material such as LiF/Al, LiO2/Al, LiF/Ca, or BaF2/Ca.
The organic layer 30 may include a hole transport layer 31, a light emitting layer 32, and a hole transport auxiliary layer 33 between the hole transport layer 31 and the light emitting layer 32.
The hole transport layer 31 is a layer for facilitating hole transport from the anode 10 to the light emitting layer 32, and may include, e.g., an amine compound.
The amine compound may include, e.g., an aryl group or a heteroaryl group. The amine compound may be, e.g., represented by Chemical Formula a or Chemical Formula b.
In Chemical Formula a and b, Ara to Arg may each independently be or include, e.g., hydrogen, deuterium, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C30 heteroaryl group, or a combination thereof.
In an implementation, at least one of Ara to Arc and at least one of Ard to Arg may be, e.g., a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C30 heteroaryl group, or a combination thereof.
Arh may be or may include, e.g., a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted C2 to C30 heteroarylene group, or a combination thereof.
The light emitting layer 32 may include at least two types of hosts and dopants, and the host may include a first compound having a bipolar characteristic having relatively strong electronic characteristic and a second compound having a bipolar characteristic having a relatively strong hole characteristic.
The first compound is a compound having a relatively strong bipolar characteristic, and may be represented by, e.g., Chemical Formula 1.
In Chemical Formula 1, Z1 to Z3 may each independently be, e.g., N or CRa.
In an implementation, at least two of Z1 to Z3 may be, e.g., N.
L1 may be or may include, e.g., a single bond or a substituted or unsubstituted C6 to C18 arylene group,
Ra and R1 to R3 may each independently be or include, e.g., hydrogen, deuterium, a hydroxyl group, a thiol group, a cyano group, a substituted or unsubstituted C1 to C20 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group.
Ar1 and Ar2 may each independently be or include, e.g., a substituted or unsubstituted C6 to C18 aryl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group.
m1 and m2 may each independently be, e.g., an integer of 1 to 4.
m3 may be, e.g., an integer of 1 to 3.
The first host compound may be represented by, e.g., Chemical Formula 1A or Chemical Formula 1B, according to the bonding position of the triphenylene group.
In Chemical Formula 1A and Chemical Formula 1B, Z1 to Z3, L1, R1 to R3, Ar1, Ar2 and m1 to m3 may be defined the same as those described above.
The first host compound may include a triphenylene group and a 6-membered ring containing at least two nitrogen atoms, e.g., a pyrimidinyl group or a triazinyl group.
The first host compound may include a pyrimidinyl group or a triazinyl group, and it may have a structure that easily accepts electrons when an electric field is applied, and thus, a driving voltage of an organic optoelectronic device including the first host compound may be lowered.
In addition, the first host compound may include a triphenylene structure that is easy to accept holes and a nitrogen-containing 6-membered ring moiety that is easy to accept electrons, thereby forming a bipolar structure to appropriately balance the flow of holes and electrons. Accordingly, the efficiency of an organic optoelectronic device including the first host compound may be improved.
In an implementation, all of Z1 to Z3 may be N.
In an implementation, L1 may be, e.g., a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, or a substituted or unsubstituted terphenylene group.
In an implementation, L1 may be, e.g., a single bond or a substituted or unsubstituted linking group of Group I.
In Group I, R29 to R31 may each independently be, e.g., hydrogen, deuterium, a halogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C3 to C20 cycloalkoxy group, a substituted or unsubstituted C1 to C20 alkylthio group, a substituted or unsubstituted C6 to C30 aralkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C6 to C30 aryloxy group, a substituted or unsubstituted C6 to C30 arylthio group, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C2 to C30 amino group, a substituted or unsubstituted C3 to C30 silyl group, a cyano group, a nitro group, a hydroxyl group, a carboxyl group, or a combination thereof.
m11 may be, e.g., an integer of 1 to 4.
m12 may be, e.g., an integer of 1 to 5.
m13 may be, e.g., an integer of 1 to 3.
* is a linking point.
In an implementation, L1 may be, e.g., a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, or a substituted or unsubstituted terphenylene group. In an implementation, L1 may be, e.g., a single bond, a substituted or unsubstituted para-phenylene group, or a substituted or unsubstituted meta-phenylene group.
In an implementation, R1 to R3 may each independently be, e.g., hydrogen, deuterium, a cyano group, a substituted or unsubstituted C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C12 aryl group.
In an implementation, R1 to R3 may each independently be, e.g., hydrogen, deuterium, a substituted or unsubstituted C1 to C5 alkyl group, or a substituted or unsubstituted phenyl group.
In an implementation, Ar1 and Ar2 may each independently be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group.
In an implementation, Ar1 and Ar2 may each independently be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group.
In an implementation, Chemical Formula 1 may be represented by, e.g., Chemical Formula 1A-1, Chemical Formula 1A-2, Chemical Formula 1A-3, Chemical Formula 1A-4, or Chemical Formula 1A-5.
In Chemical Formula 1A-1 to Chemical Formula 1A-5, Z1 to Z3, R1 to R3, Ar1, Ar2, and m1 to m3 may be defined the same as those described above.
Rc to Rd may each independently be, e.g., hydrogen, deuterium, a halogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C3 to C20 cycloalkoxy group, a substituted or unsubstituted C1 to C20 alkylthio group, a substituted or unsubstituted C6 to C30 aralkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C6 to C30 aryloxy group, a substituted or unsubstituted C6 to C30 arylthio group, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C2 to C30 amino group, a substituted or unsubstituted C3 to C30 silyl group, a cyano group, a nitro group, a hydroxyl group, a carboxyl group, or a combination thereof.
m18 and m19 may each independently be, e.g., an integer of 1 to 4.
In an implementation, Rc and Rd may each independently be, e.g., hydrogen, heavy hydrogen, a cyano group, a substituted or unsubstituted C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C12 aryl group.
In an implementation, the first compound may be represented by, e.g., Chemical Formula 1A-1, Chemical Formula 1A-2, or Chemical Formula 1A-3.
In an implementation, the first compound may be represented by, e.g., Chemical Formula 1A-2.
In an implementation, the 6-membered ring including Z1 to Z3 may be a substituted or unsubstituted pyrimidinyl group or a substituted or unsubstituted triazinyl group. In an implementation, the 6-membered ring including the Z1 to Z3 may be a substituted or unsubstituted triazinyl group. In an implementation, the first compound may be represented by, e.g., Chemical Formula 1A-a, Chemical Formula 1A-b1, Chemical Formula 1A-b2, Chemical Formula 1B-a, Chemical Formula 1B-b1, or Chemical Formula 1B-b2.
In Chemical Formula 1A-a, Chemical Formula 1A-b1, Chemical 1A-b2, Formula 1B-a, Chemical 1B-b1, and Chemical 1B-b2, L1, R1 to R3, Ar1, Ar2, and m1 to m3 may be defined the same as those described above.
In an implementation, the first compound may be, e.g., represented by Chemical Formula 1A-a, and L1 may be, e.g., a single bond or a substituted or unsubstituted phenylene group.
In an implementation, the first compound for an organic optoelectronic device may be, e.g., a compound of Group 1.
One type or two or more types of the first compound may be used.
The second compound may be included (e.g., mixed) in the light emitting layer together with the first compound to help improve luminous efficiency and life-span characteristics by increasing charge mobility and increasing stability.
The second compound may be, e.g., represented by Chemical Formula 2.
In Chemical Formula 2, Ar3 and Ar4 may each independently be or include, e.g., a substituted or unsubstituted C6 to C20 aryl group or a substituted or unsubstituted C2 to C30 heterocyclic group.
L2 and L3 may each independently be or include, e.g., a single bond or a substituted or unsubstituted C6 to C20 arylene group,
R4 to R14 may each independently be or include, e.g., hydrogen, deuterium, a cyano group, a halogen, a substituted or unsubstituted amine group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heterocyclic group.
m4 and m5 may each independently be, e.g., an integer of 1 to 3.
m6 may be, e.g., an integer of 1 to 4.
n1 may be, e.g., an integer of 0 to 2.
In an implementation, Ar3 and Ar4 of Chemical Formula 2 may each independently be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted fluorenyl group.
L2 and L3 of Chemical Formula 2 may each independently be, e.g., a single bond, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted biphenylene group.
R4 to R14 of Chemical Formula 2 may each independently be, e.g., hydrogen, deuterium, or a substituted or unsubstituted C6 to C12 aryl group.
n1 may be, e.g., 0 or 1.
For example, “substituted” in Chemical Formula 2 means that at least one hydrogen is replaced by deuterium, a C1 to C4 alkyl group, a C6 to C18 aryl group, or a C2 to C30 heteroaryl group.
In an implementation, Chemical Formula 2 may be, e.g., represented by one of Chemical Formula 2-1 to Chemical Formula 2-15.
In Chemical Formula 2-1 to Chemical Formula 2-15, m4 to m6 may be defined the same as those described above, R4 to R14 may each independently be, e.g., hydrogen, deuterium, or a substituted or unsubstituted C6 to C12 aryl group, and moieties *-L2-Ar3 and *-L3-Ar4 may each independently be, e.g., a moiety of Group II.
In Group II, D is deuterium.
m14 may be, e.g., an integer of 1 to 5.
m15 may be, e.g., an integer of 1 to 4.
m16 may be, e.g., an integer of 1 to 3.
m17 may be, e.g., 1 or 2.
* is a linking point.
In an implementation, the second compound may be represented by Chemical Formula 2-8.
In an implementation, moieties *-L2-Ar3 and *-L3-Ar4 of Chemical Formula 2-8 may each independently be, e.g., one of moiety C-1, C-2, C-3, C-4, C-7, C-8, or C-9 of Group II.
In an implementation, the second compound may be represented by, e.g., a combination of Chemical Formula 3 and Chemical Formula 4.
In Chemical Formula 3 and Chemical Formula 4, Ar5 and Ar6 may each independently be or include, e.g., a substituted or unsubstituted C6 to C20 aryl group or a substituted or unsubstituted C2 to C30 heterocyclic group,
Two adjacent ones of a1* to a4* in Chemical Formula 3 may be linking carbons linked at * of Chemical Formula 4, the remaining two of a1* to a4* of Chemical Formula 3, not linked at * of Chemical Formula 4, may be C-La-Rb. As used herein, the term “linking carbon” refers to a shared carbon at which fused rings are linked.
La, L4, and L5 may each independently be or include, e.g., a single bond or a substituted or unsubstituted C6 to C20 arylene group.
Rb and R15 to R22 may each independently be or include, e.g., hydrogen, deuterium, a cyano group, a halogen, a substituted or unsubstituted amine group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heterocyclic group.
In an implementation, the second compound represented by the combination of Chemical Formula 3 and Chemical Formula 4 may be represented by, e.g., Chemical Formula 3A, Chemical Formula 3B, Chemical Formula 3C, Chemical Formula 3D, or Chemical Formula 3E.
In Chemical Formula 3A to Chemical Formula 3E, Ar5, Ar6, L4, L5, and R15 to R22 may be defined the same as those described above.
La1 to La4 may be defined the same as L4 and L5 described above.
Rb1 to Rb4 may be defined the same as R15 to R22 described above.
In an implementation, Ar5 and Ar6 of Chemical Formulae 3 and 4 may each independently be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group.
Rb1 to Rb4 and R15 to R22 may each independently be, e.g., hydrogen, deuterium, a cyano group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group.
In an implementation, Ar5 and Ar6 in Chemical Formulas 3 and 4 may each independently be, e.g., a group of Group II.
In an implementation, Rb1 to Rb4 and R15 to R22 may each independently be, e.g., hydrogen, deuterium, a cyano group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group.
In an implementation, Rb1 to Rb4 and R15 to R22 may each independently be, e.g., hydrogen, deuterium, a cyano group, or a substituted or unsubstituted phenyl group.
In an implementation, Rb1 to Rb4, and R15 to R22 may each independently be, e.g., hydrogen, deuterium, or a substituted or unsubstituted phenyl group.
In an implementation, the second compound may be represented by, e.g., Chemical Formula 2-8, and in Chemical Formula 2-8, Ar3 and Ar4 may each independently be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group, L2 and L3 may each independently be, e.g., a single bond, or a substituted or unsubstituted C6 to C20 arylene group, and R4 to R13 may each independently be, e.g., hydrogen, deuterium, a cyano group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group.
In an implementation, the second compound may be represented by, e.g., Chemical Formula 3C, and in Chemical Formula 3C, La3 and La4 may each be a single bond, L4 and L5 may each independently be, e.g., a single bond or a substituted or unsubstituted C6 to C12 arylene group, R15 to R22, Rb3, and Rb4 may each independently be, e.g., hydrogen, deuterium, or a substituted or unsubstituted phenyl group, and Ar5 and Ar6 may each independently be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group.
In an implementation, the second compound may be, e.g., a compound of Group 2.
In an implementation, examples of a form in which at least one hydrogen in a compound B-1 to compound B-150 listed in Group 2 above is substituted with deuterium are provided below.
Dn is a number of deuterium substitutions, indicating structures with one or more deuterium substitutions.
The most specific structures of compounds B-151 to B-195 of Group 2, depending on the deuterium substitution position and substitution rate, are shown below by way of example only and are not intended to limit the scope of rights to compounds shown below.
In an implementation, deuterium may be substituted, and the deuterium substitution positions and deuterium substitution rates may be varied within the range of Compound B-1 to Compound B-195.
In an implementation, examples of a form in which at least one hydrogen in a compound C-1 to compound C-57 listed in Group 2 above is substituted with deuterium are provided below.
Dn is the number of deuterium substitutions, indicating structures with one or more deuterium substitutions.
The most specific structures of compounds C-58 to C-72 of Group 2, depending on the deuterium substitution position and substitution rate, are shown below by way of example only and are not intended to limit the scope of rights to compounds shown below.
In an implementation, when deuterium is substituted, the deuterium substitution positions and deuterium substitution rates may be varied within the range of Compound C-1 to Compound C-72.
One type or two or more types of the second compound may be used.
In the light emitting layer 32, the first compound and the second compound may be included (e.g., mixed) as a host, e.g., in a weight ratio of about 1:99 to about 99:1. Within the above range, bipolar characteristics may be implemented by matching an appropriate weight ratio using electron transport capability of the first compound and the hole transport capability of the second compound, to improve efficiency and life-span. Within this range, e.g., they may be included in a weight ratio of about 10:90 to about 90:10, about 20:80 to about 80:20, e.g., about 20:80 to about 70:30, about 20:80 to about 60:40, and about 20:80 to about 50:50. In an implementation, they may be included in a weight ratio of about 20:80, about 30:70, or about 40:60.
The light emitting layer 32 may further include one or more compounds in addition to the aforementioned first and second compounds described above as a host.
The light emitting layer 32 may further include a dopant.
The dopant may be, e.g., a phosphorescent dopant, for example a red, green or blue phosphorescent dopant, for example a red or green phosphorescent dopant.
The dopant is a material mixed with the compound for the organic optoelectronic device in a small amount to cause light emission and may be generally a material such as a metal complex that emits light by multiple excitation into a triplet or more. The dopant may be, e.g., an inorganic, organic, or organic-inorganic compound, and one or more types thereof may be used.
Examples of the dopant may include a phosphorescent dopant and examples of the phosphorescent dopant may be an organic metal compound including Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, Tm, Fe, Co, Ni, Ru, Rh, Pd, or a combination thereof. In an implementation, the phosphorescent dopant may be, e.g., a compound represented by Chemical Formula Z.
L7MX2 [Chemical Formula Z]
In Chemical Formula Z, M may be, e.g., a metal, and L7 and X2 are the same as or different from each other, and may be, e.g., ligands forming a complex compound with M.
The M may be, e.g., Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, Tm, Fe, Co, Ni, Ru, Rh, Pd, or a combination thereof, and L7 and X2 may be, e.g., a bidentate ligand.
In an implementation, the ligands represented by L7 and X2 may be, e.g., a ligand of Group A.
In Group A, R300 to R302 may each independently be, e.g., hydrogen, deuterium, a C1 to C30 alkyl group that is unsubstituted or substituted with a halogen, a C6 to C30 aryl group that is unsubstituted or substituted with a C1 to C30 alkyl, or a halogen.
R303 to R324 may each independently be, e.g., hydrogen, deuterium, a halogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C1 to C30 heteroaryl group, a substituted or unsubstituted C1 to C30 amino group, a substituted or unsubstituted C6 to C30 arylamino group, SF5, a trialkylsilyl group having a substituted or unsubstituted C1 to C30 alkyl group, a dialkylarylsilyl group having a substituted or unsubstituted C1 to C30 alkyl group and a C6 to C30 aryl group, or a triarylsilyl group having a substituted or unsubstituted C6 to C30 aryl group.
In an implementation, it may include a dopant represented by Chemical Formula V.
In Chemical Formula V, R101 to R116 may each independently be, e.g., hydrogen, deuterium, a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C6 to C20 aryl group, or —SiR132R133R134.
R132 to R134 may each independently be, e.g., a substituted or unsubstituted C1 to C6 alkyl group.
In an implementation, at least one of R101 to R116 may be, e.g., a functional group represented by Chemical Formula V-1.
L100 may be, e.g., a bidentate ligand of a monovalent anion, and may be a ligand that coordinates to iridium through a lone pair of electrons of carbon or heteroatom.
n5 and n6 may each independently be, e.g., an integer of 0 to 3, and n5+n6 may be, e.g., an integer of 1 to 3.
In Chemical Formula V-1, R135 to R139 may each independently be, e.g., hydrogen, deuterium, a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C6 to C20 aryl group, or —SiR132R133R134.
R132 to R134 may each independently be, e.g., a substituted or unsubstituted C1 to C6 alkyl group.
* means a portion linked to a carbon atom.
In an implementation, a dopant represented by Chemical Formula Z-1 may be included.
In Chemical Formula Z-1, rings A, B, C, and D may each independently represent, e.g., a 5-membered or 6-membered carbocyclic or heterocyclic ring.
RA, RB, RC, and RD may each independently represent, e.g., mono-, di-, tri-, or tetra-substitution, or unsubstitution.
LB, LC, and LD may each independently be, e.g., a direct bond, BR, NR, PR, O, S, Se, C═O, S═O, SO2, CRR′, SiRR′, GeRR′, or a combination thereof.
In an implementation, when nA is 1, LE may be, e.g., a direct bond, BR, NR, PR, O, S, Se, C═O, S═O, SO2, CRR′, SiRR′, GeRR′, or a combination thereof; and when nA is 0, LE does not exist.
RA, RB, RC, RD, R, and R′ may each independently be, e.g., hydrogen, deuterium, a halogen, an alkyl group, a cycloalkyl group, a heteroalkyl group, an arylalkyl group, an alkoxy group, an aryloxy group, an amino group, a silyl group, an alkenyl group, a cycloalkenyl group, a heteroalkenyl group, an alkynyl group, an aryl group, a heteroaryl group, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile group, an isonitrile group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, or a combination thereof. In an implementation; any adjacent RA, RB, RC, RD, R, and R′ are optionally linked to each other to provide a ring; XB, XC, XD, and XE are each independently selected from carbon and nitrogen; and Q1, Q2, Q3, and Q4 each represent oxygen or a direct bond.
The dopant according to an embodiment may be a platinum complex, and may be, e.g., represented by Chemical Formula VI.
In Chemical Formula VI, X100 may be, e.g., O, S, or NR131.
R117 to R131 may each independently be, e.g., hydrogen, deuterium, a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C6 to C20 aryl group, or —SiR132R133R134.
R132 to R134 may each independently be, e.g., a substituted or unsubstituted C1 to C6 alkyl group.
In an implementation, at least one of R117 to R131 may be, e.g., —SiR132R133R134 or a tert-butyl group.
R132 to R134 may each independently be, e.g., a substituted or unsubstituted C1 to C6 alkyl group.
The hole transport auxiliary layer 33 may include, e.g., a third compound having a relatively strong bipolar characteristic.
As described above, the light emitting layer 32 may include a first compound having a bipolar characteristic in which an electron characteristic is relatively strong and a second compound having a relatively strong hole characteristic together and thus the mobility of electrons and holes may be increased compared with the case of being used alone to significantly improve luminous efficiency.
In a device in which a material having biased electronic or hole characteristics is introduced into the light emitting layer, a recombination of carriers could occur at the interface between the light emitting layer and the electron or charge transport layer, and formation of excitons could occur relatively frequently. As a result, due to the interaction between molecular excitons in the light emitting layer and charges at the interface of the hole transport layer, a roll-off phenomenon in which efficiency is rapidly reduced could occur, and light emission life-span characteristics could also be rapidly reduced.
In view of the above, the first and second compounds may be introduced into the light emitting layer at the same time so that the light emitting region is not biased toward either the electron transport layer or the hole transport layer and in addition, a hole transport auxiliary layer including the third compound having a relatively strong bipolar characteristic may be included between the hole transport layer and the light emitting layer, and thereby, the device may be capable of preventing charge accumulation at the interface between the hole transport layer and the light emitting layer and balancing carriers in the light emitting layer. Accordingly, it is possible to improve the roll-off characteristics of the organic optoelectronic device and also significantly improve the life-span characteristics.
The third compound may be a compound represented by, e.g., Chemical Formula 5.
In Chemical Formula 5, X1 may be, e.g., C or Si.
R23 to R26 may each independently be or include, e.g., hydrogen, deuterium, a cyano group, a halogen, a substituted or unsubstituted amine group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted or unsubstituted C2 to C30 heterocyclic group.
R27 and R28 may each independently be or include, e.g., a substituted or unsubstituted C1 to C30 alkyl group or a substituted or unsubstituted C6 to C30 aryl group.
Ar7 may be or may include, e.g., a substituted or unsubstituted C6 to C30 aryl group.
Ar8 may be or may include, e.g., a substituted or unsubstituted C6 to C30 aryl group or a substituted or unsubstituted dibenzosilolyl group.
L6 to L8 may each independently be or include, e.g., a single bond or a substituted or unsubstituted C6 to C20 arylene group.
m7, m8, and m10 may each independently be, e.g., an integer of 1 to 4.
m9 may be, e.g., an integer of 1 to 3.
The third compound may be, e.g., an amine derivative that simultaneously includes a 9-substituted fluorene group and a fluorene group substituted in the phenyl direction or a dibenzosilolyl group substituted in the phenyl direction.
Due to the steric hindrance of the 9-substituted fluorene group, degradation and decomposition may be minimized by reducing the deposition temperature, so that the life-span characteristics may be further improved.
In addition, by simultaneously including the fluorene group substituted in the phenyl direction or the dibenzosilolyl group substituted in the phenyl direction, the HOMO energy level may be adjusted to facilitate hole injection.
In an implementation, the third compound may be represented by, e.g., one of Chemical Formula 5-1 to Chemical Formula 5-4.
In Chemical Formula 5-1 to Chemical Formula 5-4, X1, R23 to R28, Ar7, Ar8, L6 to L8, and m7 to m10 may be defined the same as those described above.
In an implementation, the third compound may be represented by, e.g., Chemical Formula 5-2.
In an implementation, Ar7 in Chemical Formula 5 may be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group.
In an implementation, Ar7 in Chemical Formula 5 may be, e.g., a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group.
In an implementation, Ar8 in Chemical Formula 5 may be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted phenanthrenyl group, a substituted or unsubstituted triphenylene group, a substituted or unsubstituted fluorenyl group, or a substituted or unsubstituted dibenzosilolyl group.
In an implementation, Ar8 in Chemical Formula 5 may be, e.g., a group of Group III.
In Group III, the groups may be substituted or unsubstituted.
In an implementation, when substituted, the substituent may be deuterium, a substituted or unsubstituted C1 to C5 alkyl group, or a substituted or unsubstituted C6 to C12 aryl group, and * is a linking point.
In an implementation, Ar8 in Chemical Formula 5 may be, e.g., a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted triphenylene group, or a substituted or unsubstituted fluorenyl group.
In an implementation, L6 to L8 in Chemical Formula 5 may each independently be, e.g., a single bond or a substituted or unsubstituted C6 to C12 arylene group.
In an implementation, R23 to R26 in Chemical Formula 5 may each independently be, e.g., hydrogen, deuterium, a cyano group, a substituted or unsubstituted C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C30 aryl group.
In an implementation, R27 and R28 in Chemical Formula 5 may each independently be, e.g., a substituted or unsubstituted C1 to C10 alkyl group or a substituted or unsubstituted C6 to C20 aryl group.
In an implementation, the third compound may be, e.g., a compound of Group 3.
In an implementation, the first compound may be represented by, e.g., Chemical Formula 1A-2, the second compound may be represented by, e.g., Chemical Formula 2 8, and the third compound may be represented by, e.g., Chemical Formula 5-2.
In an implementation, the organic layer 30 may further include an electron transport region.
The electron transport region may help further increase electron injection and/or electron mobility between the cathode 20 and the light emitting layer 32 and block holes.
Specifically, the electron transport region may include an electron transport layer 34 between the cathode 20 and the light emitting layer 32, and an electron transport auxiliary layer between the light emitting layer 32 and the electron transport layer 34, and at least one of the compounds listed in Group B may be included in at least one of the electron transport layer and the electron transport auxiliary layer.
In an implementation, the organic light emitting diode may further include an electron injection layer, a hole injection layer, and the like, in addition to the light emitting layer as the aforementioned organic layer.
The organic light emitting diode may be produced by forming an anode or a cathode on a substrate form an organic layer by a dry film-forming method such as evaporation, sputtering, plasma plating, and ion plating, and forming a cathode or an anode thereon.
The aforementioned organic light emitting diode may be applied to an organic light emitting display device.
The following Examples and Comparative Examples are provided in order to highlight characteristics of one or more embodiments, but it will be understood that the Examples and Comparative Examples are not to be construed as limiting the scope of the embodiments, nor are the Comparative Examples to be construed as being outside the scope of the embodiments. Further, it will be understood that the embodiments are not limited to the particular details described in the Examples and Comparative Examples.
Hereinafter, the starting materials and reactants used in examples and synthesis examples were purchased from Sigma-Aldrich, TCI, Tokyo chemical industry, or P&H tech or synthesized through a suitable method, unless otherwise specified.
(Synthesis of Compounds)
Compounds were synthesized through the following steps.
Compound A-32 was synthesized by referring to the synthesis method described in Korean Patent Application No. KR 10-2018-0099436.
Compound ET-1 was synthesized by referring to a synthesis method described in Korean Patent Application No. KR 10-2021-0058523.
In a 250 mL round flask, 1 equivalent of N-phenyl-3,3-bicarbazole, 1 equivalent of 3-bromo-9-phenylcarbazole, 1.5 equivalents of sodium t-butoxide and 0.03 equivalent of tris(dibenzylideneacetone) dipalladium, and 0.06 equivalent of tri t-butylphosphine were mixed with xylene (to form a 0.3 M solution) and heated under reflux for 15 hours under a nitrogen flow. The mixture obtained therefrom was added to 300 mL of methanol to filter the crystallized solids, dissolved in dichlorobenzene, filtered through silica gel/Celite, and after removing an appropriate amount of organic solvent, the resultant was recrystallized with methanol to obtain Compound B-40 at a yield of 60%.
LC/MS calculated for: C48H31N3 Exact Mass: 649.2518 found for: 649.25.
Compound B-136 was synthesized by referring to the synthesis method described in U.S. Pat. No. 10,476,008 B2.
HRMS (70 eV, EI+): m/z calcd for C42H28N2: 560.2252, found: 560.
Elemental Analysis: C, 90%; H, 5%
7.12 g (26.1 mmol) of Int-1, 11 g (22.7 mmol) of Int-2 (CAS No. 2305719-96-2), and 3.48 g (36.2 mmol) of sodium t-butoxide were placed in a round bottom flask and toluene 230 m1 was added thereto and dissolved. 1.04 g (1.13 mmol) of Pd2(dba)3 and 0.92 g (2.27 mmol) of tri-tert-butylphosphine were sequentially added thereto, followed by stirring under reflux for 6 hours under a nitrogen atmosphere. After the reaction is completed, the toluene solvent was removed, the resultant was extracted with dichloromethane and distilled water, the organic layer was dried over magnesium sulfate, filtered, and the filtrate was concentrated under reduced pressure. The product was purified by recrystallization with n-hexane/dichloromethane to obtain 13.4 g (yield 87%) of Compound D-9.
Compound D-2 was synthesized in the same manner as in Synthesis Example 4, except for using Int-3 (CAS No. 1853122-02-7) instead of Int-2.
Compound D-30 was synthesized in the same manner as in Synthesis Example 4, except for using Int-4 (CAS No. 1154752-04-1) and Int-3 (CAS No. 1853122-02-7) instead of Int-1 and Int-2.
Compound D-37 was synthesized in the same manner as in Synthesis Example 4, except for using Int-4 (CAS No. 1154752-04-1) and Int-2 (CAS No. 2305719-96-2) instead of Int-1 and Int-2.
Compound R-1 was synthesized by referring to the synthesis method described in Korean Patent Application No. KR 10-2018-0037889.
A glass substrate coated with a thin film of indium tin oxide (ITO) was washed with distilled water and ultrasonic waves. After washing with the distilled water, the glass substrate was ultrasonic wave-washed with isopropyl alcohol, acetone, or methanol, and dried and then, moved to a plasma cleaner, cleaned by using oxygen plasma for 10 minutes, and moved to a vacuum depositor. This prepared ITO transparent electrode was used as an anode, Compound A doped with 3% NDP-9 (Novaled GmbH) was vacuum-deposited on the ITO substrate to form a 100 Å-thick hole injection layer, and Compound A is deposited on the hole injection layer to a thickness of 1,350 Å to form a hole transport layer. On the hole transport layer, Compound D-9 obtained in Synthesis Example 4 was deposited at a thickness of 320 Å to form a hole transport auxiliary layer, and on the hole transport auxiliary layer, Compound A-32 of Synthesis Example 1 and Compound B-40 of Synthesis Example 2 were simultaneously used as a host and 10 wt % of GD as a dopant was used to form a 330 Å-thick light emitting layer by vacuum deposition. Subsequently, on the light emitting layer, Compound B was deposited at a thickness of 50 Å to form an electron transport auxiliary layer and Compound C and LiQ were simultaneously vacuum-deposited in a weight ratio of 1:1 to form a 300 Å-thick electron transport layer. On the electron transport layer, LiQ and Al were sequentially vacuum-deposited to be 15 Å-thick and 1,200 Å-thick, manufacturing an organic light emitting diode.
ITO/Compound A (3% NDP-9 doping, 100 Å)/Compound A (1,350 Å)/Compound D-9 (320 Å)/EML [host (Compound A-32:Compound B-40=30:70): GD=90 wt %:10 wt %] (330 Å)/Compound B (50 Å)/Compound C:LiQ (300 Å)/LiQ (15 Å)/Al (1,200 Å).
Compound A: N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine
Compound B: 2-{3-[3-(9,9-dimethyl-9H-fluoren-2-1)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine
Compound C: 4-(4-{4-[4-(diphenyl-1,3,5-triazin-2-yl)phenyl]naphthalene-1-yl}phenyl)benzonitrile
Diodes of Examples 2 to 4 and Comparative Examples 1 and 2 were manufactured in the same manner as in Example 1, except that the hole transport auxiliary layers and/or the hosts were changed as shown in Tables 1 and 2.
Evaluation
The driving voltage, luminous efficiency, and life-span characteristics of the organic light emitting diodes according to Examples 1 to 4 and Comparative Examples 1 and 2 were evaluated.
Specific measuring methods were as follows, and the results are shown in Tables 1 and 2.
(1) Measurement of Current Density Change Depending on Voltage Change
The obtained organic light emitting diodes were measured regarding a current value flowing in the unit device, while increasing the voltage from 0 V to 10 V using a current-voltage meter (Keithley 2400), and the measured current value was divided by area to provide the results.
(2) Measurement of Luminance Change Depending on Voltage Change
Luminance was measured by using a luminance meter (Minolta Cs-1000A), while the voltage of the organic light emitting diodes was increased from 0 V to 10 V.
(3) Measurement of Luminous Efficiency
Luminous efficiency (cd/A) at the same current density (10 mA/cm2) were calculated by using the luminance and current density from the items (1) and (2), and voltages (V).
Relative values based on the luminous efficiency of Comparative Example 1 are shown in Table 1.
Relative values based on the luminous efficiency of Comparative Example 2 are shown in Table 2.
(4) Measurement of Life-Span
The results were obtained by measuring a time when current efficiency (cd/A) was decreased down to 90%, while luminance (cd/m2) was maintained to be 24000 cd/m2.
Relative values based on the life-span of Comparative Example 1 are shown in Table 1.
(5) Measurement of Driving Voltage
A driving voltage of each diode was measured using a current-voltage meter (Keithley 2400) at 15 mA/cm2 to obtain the results.
Relative values based on the driving voltage of Comparative Example 2 are shown in Table 2.
Referring to Tables 1 and 2, the organic light emitting diodes including the compositions according to the Examples exhibited significantly improved driving voltage, efficiency, and life-span characteristics, compared to the organic light emitting diode according to the Comparative Examples.
One or more embodiments may provide an organic optoelectronic device capable of implementing high efficiency and long life-span characteristics.
Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0053707 | Apr 2022 | KR | national |
