Metal-assisted delayed fluorescent materials as co-host materials for fluorescent OLEDs
A light emitting device includes a first electrode, a hole transporting layer in contact with the first electrode, a second electrode, an electron transporting layer in contact with the second electrode; and an emissive layer between the hole transporting layer and the electron transporting layer. The emissive layer includes a metal-assisted delayed fluorescent (MADF) emitter, a fluorescent emitter, and a host, and the MADF emitter harvests electrogenerated excitons and transfers energy to the fluorescent emitter.
1. A light emitting device comprising:
a first electrode;
a hole transporting layer in contact with the first electrode;
a second electrode;
an electron transporting layer in contact with the second electrode; and
an emissive layer between the hole transporting layer and the electron transporting layer, wherein the emissive layer comprises:
n emitter layers comprising a host and an acceptor; and
m donor layers comprising the host and a donor;
wherein:
n and m are integers ≥1
the donor is a metal-assisted delayed fluorescent (MADF) emitter that demonstrates an emission spectrum consisting of dual emission characteristics from delayed fluorescence and phosphorescence,
the acceptor is a fluorescent emitter,
the delayed fluorescence emission energy of the donor is greater than the emission energy of the acceptor and the phosphorescence emission energy of the donor is greater than or less than the emission energy of the acceptor, such that an emission spectrum of the donor partially overlaps in wavelength with an absorption spectrum of the acceptor, and
dipole coupling between the donor in an excited state and the acceptor in a ground state allows a transfer of energy from the donor to the acceptor.
2. The light emitting device of claim 1 , wherein n and m are integers >1.
3. The light emitting device of claim 2 , wherein n and m are equal.
4. The light emitting device of claim 2 , wherein each emitter layer is adjacent to at least one donor layer.
5. The light emitting device of claim 2 , wherein n=m+1, or m=n+1.
6. The light-emitting device of claim 1 , wherein light emission from the light-emitting device is primarily from the acceptor.
7. The light emitting device of claim 1 , wherein the donor is a compound of structure (a) or (b):
wherein:
M is platinum (II), palladium (II), nickel (II), manganese (II), zinc (II), gold (III), silver (III), copper (III), iridium (I), rhodium (I), or cobalt (I);
A is an accepting group having one of the following structures, which can optionally be substituted:
D is a donor group having one of the following structures, which can optionally be substituted:
C has one of the following structures, which can optionally be substituted:
N has one of the following structures, which can optionally be substituted:
each of a 0 , a 1 , and a 2 is independently present or absent, and if present, is a direct bond or linking group having one of the following structures:
each of b 1 and b 2 is independently present or absent, and if present, comprises a linking group comprising one or more of the following structures:
X is B, C, N, O, Si, P, S, Ge, As, Se, Sn, Sb, or Te,
Y is N, P, P═O, As, As═O, CH, CR, SiH, SiR, GeH, GeR,
each R is independently hydrogen, deuterium, halogen, hydroxyl, thiol, nitro, cyano, nitrile, isonitrile, sulfinyl, mercapto, sulfo, carboxyl, hydrazino; substituted or unsubstituted: aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, alkyl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, alkoxycarbonyl, acylamino, alkoxy carbonylamino, aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio, ureido, phosphoramide, silyl, polymeric, or any conjugate or combination thereof, and
n is an integer that satisfies the valency of Y.
8. The light emitting device of claim 7 , wherein a 2 is absent.
9. The light emitting device of claim 7 , wherein a 2 and b 2 are absent.
10. The light emitting device of claim 7 , wherein X is N.
11. The light emitting device of claim 7 , wherein A is
a 2 is absent, b 2 is absent, and D is
12. The light emitting device of claim 7 , wherein C in structure (a) or (b) is
13. The light emitting device of claim 7 , wherein N in structure (a) or (b) is
or substituted
14. The light emitting device of claim 7 , wherein M is palladium (II).
15. The light emitting device of claim 7 , wherein the donor is one of the following:
16. The light emitting device of claim 7 , wherein the donor is a compound of General Formula A:
wherein:
M is Ir, Rh, Mn, Ni, Cu, or Ag;
each R 1 and R 2 is independently hydrogen, halogen, hydroxyl, nitro, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 1a and Y 1b is independently O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , or a combination thereof, wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure;
each of Y 2a , Y 2b , Y 2c , and Y 2d is independently N or CR 5 , wherein R 5 is hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 3a , Y 3b , Y 3c , Y 3d , Y 4a , Y 4b , Y 4c , and Y 4d is independently N, O, S, NR 6 , or CR 7 , wherein each of R 6 and R 7 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene; or Z(R 8 ) 2 , wherein Z is C or Si, and wherein each R 8 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of m and n is independently 1 or 2; and
each
independently represents partial or full unsaturation of the ring with which it is associated.
17. The light emitting device of claim 16 , wherein Y 2b is C; Y 2c , Y 3b and Y 4b are N; and M is Ir or Rh.
18. The light emitting device of claim 7 , wherein the donor is a compound of General Formula B:
wherein:
M is Pt, Pd, or Au;
each of R 1 and R 2 is independently hydrogen, halogen, hydroxyl, nitro, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 1a and Y 1b is independently O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , or a combination thereof, wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure;
each of Y 2a , Y 2b , Y 2c , and Y 2d is independently N or CR 5 , wherein R 5 is hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 3a , Y 3b , Y 3c , Y 3d , Y 3e , Y 3f , Y 4a , Y 4b , Y 4c , and Y 4d is independently N, O, S, NR 6 , CR 7 , wherein each of R 6 and R 7 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene; or Z(R 8 ) 2 , wherein Z is C or Si, and wherein each R 8 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
m is 1 or 2; and
each
independently represents partial or full unsaturation of the ring with which it is associated.
19. The light emitting device of claim 18 , wherein M is Pt or Pd, Y 2b and Y 2c are C, Y 3b and Y 4b are N, each of Y 1a and Y 1b is independently O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , or a combination thereof, wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure.
20. The light emitting device of claim 18 , wherein M is Au, Y 2b , Y 2c and Y 4b are C, Y 3b is N, each of Y 1a and Y 1b is independently O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , or a combination thereof, wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure.
21. The light emitting device of claim 7 , wherein the donor is a compound of General Formula C:
wherein:
M is Pt, Pd, Au, or Ag;
each of R 1 and R 2 is independently hydrogen, halogen, hydroxyl, nitro, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
one of Y 1a and Y 1b is B(R 3 ) 2 and the other of Y 1a and Y 1b is O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure;
each of Y 2a , Y 2b , Y 2c , and Y 2d is independently N or CR 5 , wherein R 5 is hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 3a , Y 3b , Y 3c , Y 3d , Y 4a , Y 4b , Y 4c , and Y 4d is independently N, O, S, NR 6 , CR 7 , wherein each of R 6 and R 7 independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene; or Z(R 8 ) 2 , wherein Z is C or Si, and wherein each R 8 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of m and n is independently 1 or 2; and
each
independently represents partial or full unsaturation of the ring with which it is associated.
22. The light emitting device of claim 7 , wherein the donor is a compound of General Formula D:
wherein:
M is Ir, Rh, Pt, Os, Zr, Co, or Ru;
each of R 1 and R 2 is independently hydrogen, halogen, hydroxyl, nitro, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 1a , Y 1b , Y 1c and Y 1d is independently O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure;
Y 1c , if present, is O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure;
each of Y 2a , Y 2b , Y 2c , and Y 2d is independently N or CR 5 , wherein R 5 is hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 3a , Y 3b , Y 3c , Y 3d , Y 3e , Y 4a , Y 4b , Y 4c , and Y 4d is independently N, O, S, NR 6 , or CR 7 , wherein each of R 6 and R 7 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene; or Z(R 8 ) 2 , wherein Z is C or Si, and wherein each R 8 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 5a , Y 5b , Y 5c , Y 5d , Y 6a , Y 6b , Y 6c , and Y 6d is independently N, O, S, NR 5 , or
CR 6 ; each of m, n, I, and p is independently 1 or 2; and
each
independently represents partial or full unsaturation of the ring with which it is associated.
23. The light emitting device of claim 7 , wherein the donor is a compound of General Formula E:
wherein:
M is Pt, Pd, Ir, Rh, Au, Co, Mn, Ni, Ag, or Cu;
each of Y 1a and Y 1b is independently O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , wherein each of R 3 and R 4 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure;
each of Y 2a , Y 2b , Y 2c , Y 2d , Y 2e , Y 2f , Y 2g , and Y 2h is independently N or CR 5 , wherein R 5 is hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 3a , Y 3b , Y 3c , Y 3d , Y 3e , Y 4a , Y 4b , Y 4c , Y 4d and Y 4e is independently N, O, S, NR 6 , or CR 7 , wherein each of R 6 and R 7 independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene; or Z(R 8 ) 2 , wherein Z is C or Si, and wherein each R 8 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, aminoalkoxy, haloalkyl, arylalkane, or arylalkene;
m is 1 or 2;
n is 1 or 2;
each
independently represents partial or full unsaturation of the ring with which it is associated; and
each of Fl 1 , Fl 2 , Fl 3 and Fl 4 is independently present or absent, with at least one of Fl 1 , Fl 2 , Fl 3 and Fl 4 present, and if present each of Fl 1 , Fl 2 , Fl 3 and Fl 4 is a fluorescent emitter covalently bonded to one of Y 2a , Y 2d , Y 2e , Y 2f , Y 2g , Y 2h , Y 3c , Y 3d , Y 3e , Y 4c , Y 4d and Y 4e .
24. The light emitting device of claim 7 , wherein the donor has an energy of the singlet excited state(s) no more than 0.2 eV greater than the energy of the lowest triplet state, and the donor emits simultaneously from the lowest triplet state and the singlet excited state(s) at room temperature or elevated temperature.
25. The light emitting device of claim 24 , wherein the donor harvests electrogenerated singlet and triplet excitons.
26. The light emitting device of claim 23 , wherein each of Fl 1 , Fl 2 , Fl 3 , Fl 4 , if present, has one of the following structures:
1. Aromatic Hydrocarbons and Their Derivatives
2. Arylethylene, Arylacetylene and Their Derivatives
wherein R al , R bl , R cl , R dl , R el , R fl , R gl , R hl and R il can be one of the following structure:
3. Heterocyclic Counpounds and Their Derivatives
4. Other fluorescent luminophors
wherein:
each of R 1l , R 2l , R 3l , R 4l , R 5l , R 6l , R 7l and R 8l is independently hydrogen, deuterium, halogen, hydroxyl, thiol, nitro, cyano, nitrile, isonitrile, sulfinyl, mercapto, sulfo, carboxyl, hydrazino; substituted or unsubstituted: aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, alkyl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, alkoxycarbonyl, acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio, ureido, phosphoramide, silyl, polymeric, or any conjugate or combination thereof, and
each of Y a , Y b , Y c , Y d , Y e , Y f , Y g , Y h , Y i , Y j , Y k , Y l , Y m , Y n , Y 0 and Y p is independently C, N or B; and
each of U a , U b and U c is independently CH 2 , CRR, C═O, SiRR, GeH 2 , GeRR 2 , NH, NR, PH, PR, RP═O, AsR, RAs═O, O, S, S═O, SO 2 , Se, Se═O, SeO 2 , BH, BR, RBi═O, BiH, or BiR, wherein each R is independently hydrogen, deuterium, halogen, hydroxyl, thiol, nitro, cyano, nitrile, isonitrile, sulfinyl, mercapto, sulfo, carboxyl, hydrazino; substituted or unsubstituted: aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, alkyl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, alkoxycarbonyl, acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio, ureido, phosphoramide, silyl, polymeric, or any conjugate or combination thereof.
27. The light emitting device of claim 1 , wherein the acceptor comprises one of the following compounds:
wherein R al , R bl , R cl , R dl , R el , R fl , R gl , R hl and R il can be one of the following structure:
3. Heterocyclic Counpounds and Their Derivatives
4. Other fluorescent luminophors
wherein:
each of R 1l , R 2l , R 3l , R 4l , R 5l , R 6l , R 7l and R 8l is independently hydrogen, deuterium, halogen, hydroxyl, thiol, nitro, cyano, nitrile, isonitrile, sulfinyl, mercapto, sulfo, carboxyl, hydrazino; substituted or unsubstituted: aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, alkyl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, alkoxycarbonyl, acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio, ureido, phosphoramide, silyl, polymeric, or any conjugate or combination thereof, and
each of Y a , Y b , Y c , Y d , Y e , Y f , Y g , Y h , Y i , Y j , Y k , Y l , Y m , Y n , Y o and Y p is independently C, N or B; and
each of U a , U b and U c is independently CH 2 , CRR, C═O, SiRR, GeH 2 , GeRR 2 , NH, NR, PH, PR, RP═O, AsR, RAs═O, O, S, S═O, SO 2 , Se, Se═O, SeO 2 , BH, BR, RBi═O, BiH, or BiR, wherein each R is independently hydrogen, deuterium, halogen, hydroxyl, thiol, nitro, cyano, nitrile, isonitrile, sulfinyl, mercapto, sulfo, carboxyl, hydrazino; substituted or unsubstituted: aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, alkyl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, alkoxycarbonyl, acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio, ureido, phosphoramide, silyl, polymeric, or any conjugate or combination thereof.