Light-emitting device and electronic apparatus including the same
Provided are a light-emitting device and an electronic apparatus including the light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer disposed between the first electrode and the second electrode. The interlayer includes an emission layer and an n-doping layer disposed between the emission layer and the second electrode. The emission layer includes a first compound, a second compound, and a light-emitting dopant, the n-doping layer includes a third compound and an n-dopant, and does not include the light-emitting dopant, the first compound includes a hole transport host, the second compound and the third compound each independently include an electron transport host, a bipolar host, or any combination thereof, and the second compound and the third compound are identical to or different from each other.
1. A light-emitting device comprising:
a first electrode;
a second electrode facing the first electrode, and
an interlayer disposed between the first electrode and the second electrode, the interlayer including:
an emission layer; and
an n-doping layer disposed between the emission layer and the second electrode,
wherein
the emission layer includes a first compound, a second compound, and a light-emitting dopant,
the n-doping layer includes a third compound and an n-dopant, and does not include the light-emitting dopant,
the first compound includes a hole transport host,
the second compound and the third compound each independently include an electron transport host, a bipolar host, or a combination thereof, and
the second compound and the third compound are identical to each other.
2. The light-emitting device of claim 1 , wherein the n-doping layer directly contacts the emission layer.
3. The light-emitting device of claim 1 , wherein the n-dopant includes a metal-containing material including an alkali metal complex, an alkaline earth metal complex, or a combination thereof.
4. The light-emitting device of claim 1 , wherein the n-dopant includes a Li complex.
5. The light-emitting device of claim 1 , wherein an amount of the n-dopant in the n-doping layer is in a range of about 5 wt % to about 10 wt %, based on the total weight of the n-doping layer.
6. The light-emitting device of claim 1 , wherein a thickness of the n-doping layer is in a range of about 1 nm to about 20 nm.
7. The light-emitting device of claim 1 , wherein the first compound includes a compound represented by Formula 1-1, a compound represented by Formula 1-2, or a combination thereof:
wherein in Formulae 1-1 and 1-2,
A 11 to A 14 are each independently a π electron-rich C 3 -C 60 cyclic group,
R 11 to R 14 are each independently a group represented by *-(L 13 ) a13 -(Ar 13 ) b13 , hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C 1 -C 60 alkyl group unsubstituted or substituted with at least one R 10b , a C 2 -C 60 alkenyl group unsubstituted or substituted with at least one R 10b , a C 2 -C 60 alkynyl group unsubstituted or substituted with at least one R 10b , a C 1 -C 60 alkoxy group unsubstituted or substituted with at least one R 10b , a π electron-rich C 3 -C 60 cyclic group unsubstituted or substituted with at least one R 10b , —Si(Q 1 )(Q 2 )(Q 3 ), —N(Q 1 )(Q 2 ), or —B(Q 1 )(Q 2 ),
c11 to c14 are each independently an integer from 1 to 8,
L 11 to L 13 are each independently:
a single bond; or
a π electron-rich C 3 -C 60 cyclic group unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C 1 -C 60 alkyl group, a C 1 -C 60 alkoxy group, a π electron-rich C 3 -C 60 cyclic group, or a combination thereof,
a11 to a13 are each independently an integer from 1 to 5,
Ar 11 to Ar 13 are each independently:
a π electron-rich C 3 -C 60 cyclic group unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C 1 -C 60 alkyl group, a C 1 -C 60 alkoxy group, a π electron-rich C 3 -C 60 cyano group, or any combination thereof, or
—Si(Q 1 )(Q 2 )(Q 3 ) or —N(Q 1 )(Q 2 ),
b11 to b13 are each independently an integer from 1 to 5, and
R 10 b is:
deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group;
a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, or a C 1 -C 60 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a π electron-rich C 3 -C 60 cyclic group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, —Si(Q 11 )(Q 12 )(Q 13 ), —N(Q 11 )(Q 12 ), —B(Q 11 )(Q 12 ), or a combination thereof;
a π electron-rich C 3 -C 60 cyclic group, a C 6 -C 60 aryloxy group, or C 6 -C 60 arylthio group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a π electron-rich C 3 -C 60 cyclic group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, —Si(Q 21 )(Q 22 )(Q 23 ), —N(Q 21 )(Q 22 ), —B(Q 21 )(Q 22 ), or a combination thereof; or
—Si(Q 31 )(Q 32 )(Q 33 ), —N(Q 31 )(Q 32 ), or —B(Q 31 )(Q 32 ),
wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C 1 -C 60 alkyl group; a C 2 -C 60 alkenyl group; a C 2 -C 60 alkynyl group; a C 1 -C 60 alkoxy group; or a x electron-rich C 3 -C 60 cyclic group unsubstituted or substituted with deuterium, —F, a cyano group, a C 1 -C 60 alkyl group, a C 1 -C 60 alkoxy group, a phenyl group, a biphenyl group, or a combination thereof.
8. The light-emitting device of claim 1 , wherein
the electron transport host is a compound that contains at least one electron withdrawing group,
the bipolar host is a compound that includes at least one electron withdrawing group and at least one electron donating group,
the electron withdrawing group is:
—F, —CFH 2 , —CF 2 H, —CF 3 , —CN, or —NO 2 ;
a C 1 -C 60 alkyl group substituted with —F, —CFH 2 , —CF 2 H, —CF 3 , —CN, —NO 2 , or any combination thereof; or
a π electron-deficient nitrogen-containing C 1 -C 60 cyclic group,
the electron donating group is
a carbazole group, a dibenzofuran group, a dibenzothiophene group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, or —N(Q 1 )(Q 2 ),
wherein Q 1 to Q 2 are each independently: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C 1 -C 60 alkyl group; a C 2 -C 60 alkenyl group; a C 2 -C 60 alkynyl group; a C 1 -C 60 alkoxy group; or a π electron-rich C 3 -C 60 cyclic group unsubstituted or substituted with deuterium, —F, a cyano group, a C 1 -C 60 alkyl group, a C 1 -C 60 alkoxy group, a phenyl group, a biphenyl group, or a combination thereof.
9. The light-emitting device of claim 1 , wherein the second compound includes a compound represented by Formula 2-1, a compound represented by Formula 2-2, a compound represented by Formula 2-3, or a combination thereof:
wherein in Formulae 2-1 to 2-3,
A 21 to A 26 are each independently a C 3 -C 60 carbocyclic group or a C 1 -C 60 heterocyclic group,
X 21 is N-[(L 21 ) a21 -(Ar 21 ) b21 ], O, or S,
X 22 to X 24 are each independently N or C(R 21 ),
at least one of X 22 to X 24 is N,
L 21 to L 27 are each independently a single bond, a C 3 -C 60 carbocyclic group unsubstituted or substituted with at least one R 10a , or a C 1 -C 60 heterocyclic group unsubstituted or substituted with at least one R 10a ,
a21 to a27 are each independently an integer from 1 to 3,
Ar 21 to Ar 26 and R 21 to R 25 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C 1 -C 60 alkyl group unsubstituted or substituted with at least one R 10a , a C 2 -C 60 alkenyl group unsubstituted or substituted with at least one R 10a , a C 2 -C 60 alkynyl group unsubstituted or substituted with at least one R 10a , a C 1 -C 60 alkoxy group unsubstituted or substituted with at least one R 10a , a C 3 -C 60 carbocyclic group unsubstituted or substituted with at least one R 10a , a C 1 -C 60 heterocyclic group unsubstituted or substituted with at least one R 10a , a C 6 -C 60 aryloxy group unsubstituted or substituted with at least one R 10a , a C 6 -C 60 arylthio group unsubstituted or substituted with at least one R 10a , —Si(Q 1 )(Q 2 )(Q 3 ), —N(Q 1 )(Q 2 ), —B(Q 1 )(Q 2 ), —C(═O)(Q 1 ), —S(═O) 2 (Q 1 ), or —P(═O)(Q 1 )(Q 2 ),
b21 to b26 are each independently an integer from 1 to 5,
c22 to c25 are each independently an integer from 1 to 8,
at least one of A 21 , A 22 , L 21 to L 23 , and Ar 21 to Ar 23 in Formula 2-1 includes a π electron-deficient nitrogen-containing C 1 -C 60 cyclic group,
at least one of R 22 to R 25 in Formula 2-3 includes an electron withdrawing group,
the electron withdrawing group is:
—F, —CFH 2 , —CF 2 H, —CF 3 , —CN, or —NO 2 ;
a C 1 -C 60 alkyl group substituted with —F, —CFH 2 , —CF 2 H, —CF 3 , —CN, —NO 2 , or a combination thereof; or
a π electron-deficient nitrogen-containing C 1 -C 60 cyclic group, R 10a is:
deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group;
a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, or a C 1 -C 60 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C 3 -C 60 carbocyclic group, a C 1 -C 60 heterocyclic group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, —Si(Q 11 )(Q 12 )(Q 13 ), —N(Q 11 )(Q 12 ), —B(Q 11 )(Q 12 ), —C(═O)(Q 11 ), —S(═O) 2 (Q 11 ), —P(═O)(Q 11 )(Q 12 ), or a combination thereof;
a C 3 -C 60 carbocyclic group, a C 1 -C 60 heterocyclic group, a C 6 -C 60 aryloxy group, or a C 6 -C 60 arylthio group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C 1 -C 60 alkyl group, a C 2 -C 60 alkenyl group, a C 2 -C 60 alkynyl group, a C 1 -C 60 alkoxy group, a C 3 -C 60 carbocyclic group, a C 1 -C 60 heterocyclic group, a C 6 -C 60 aryloxy group, a C 6 -C 60 arylthio group, —Si(Q 21 )(Q 22 )(Q 23 ), —N(Q 21 )(Q 22 ), —B(Q 21 )(Q 22 ), —C(═O)(Q 21 ), —S(═O) 2 (Q 21 ), —P(═O)(Q 21 )(Q 22 ), or a combination thereof; or
—Si(Q 31 )(Q 32 )(Q 33 ), —N(Q 31 )(Q 32 ), —B(Q 31 )(Q 32 ), —C(═O) (Q 31 ), —S(═O) 2 (Q 31 ), or —P(═O)(Q 31 )(Q 32 ),
wherein Q 1 to Q 3 , Q 11 to Q 13 , Q 21 to Q 23 , and Q 31 to Q 33 are each independently: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C 1 -C 60 alkyl group; a C 2 -C 60 alkenyl group; a C 2 -C 60 alkynyl group; a C 1 -C 60 alkoxy group; or a C 3 -C 60 carbocyclic group or a C 1 -C 60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C 1 -C 60 alkyl group, a C 1 -C 60 alkoxy group, a phenyl group, a biphenyl group, or a combination thereof.
10. The light-emitting device of claim 1 , wherein the second compound has a triplet energy (T1) level equal to or greater than about 2.85 eV.
11. The light-emitting device of claim 1 , wherein
the light-emitting dopant in the emission layer includes a first dopant, a second dopant, or a combination thereof,
the first dopant is a phosphorescent dopant, and
the second dopant is a thermally activated delayed fluorescence dopant satisfying Equation 1:
Δ E ST =E ( S 1)− E ( T 1)≤0.3 eV [Equation 1]
wherein in Equation 1,
E(S1) is the lowest excitation singlet energy level (eV) of the thermally activated delayed fluorescence dopant, and
E(T1) is the lowest excitation triplet energy level (eV) of the thermally activated delayed fluorescence dopant.
12. The light-emitting device of claim 11 , wherein the light-emitting dopant in the emission layer further includes a fluorescence dopant.
13. The light-emitting device of claim 1 , wherein
the interlayer further includes:
a hole transport region between the first electrode and the emission layer; and
an electron transport region between the n-doping layer and the second electrode,
the hole transport region includes a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or a combination thereof, and
the electron transport region includes a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, an electron injection layer, or a combination thereof.
14. The light-emitting device of claim 13 , wherein
the hole transport region includes a hole transport layer,
the hole transport layer includes a hole transport material, and
the hole transport material included in the hole transport layer and the first compound included in the emission layer are identical to each other.
15. The light-emitting device of claim 13 , wherein
the electron transport region includes an electron transport layer,
the n-doping layer is disposed between the emission layer and the electron transport layer, and
the n-doping layer directly contacts the emission layer and directly contacts the electron transport layer.
16. The light-emitting device of claim 13 , wherein the electron transport region includes a Li complex.
17. An electronic apparatus comprising the light-emitting device of claim 1 .
18. The electronic apparatus of claim 17 , further comprising a thin-film transistor including a source electrode, a drain electrode, and an active layer, wherein
the first electrode of the light-emitting device and the source electrode or the drain electrode of the thin-film transistor are electrically connected to each other.
19. The electronic apparatus of claim 17 , further comprising a functional layer including a touch screen layer, a polarizing layer, a color filter, a color conversion layer, or a combination thereof.