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US-20260130112-A1 - ORGANIC ELECTROLUMINESCENT DEVICE

US20260130112A1US 20260130112 A1US20260130112 A1US 20260130112A1US-20260130112-A1

Abstract

Provided is an organic electroluminescent device. The organic electroluminescent device has an organic layer comprising at least a fluorescent material and a metal complex. The fluorescent material has a structure represented by Formula 1, and the metal complex comprises a ligand with a structure represented by Formula 2. The organic electroluminescent device uses a phosphorescent material to sensitize the fluorescent material so that the prepared organic electroluminescent device has a narrower full width at half maximum and higher efficiency. Further provided is a display apparatus comprising the organic electroluminescent device.

Inventors

  • Chunliang Zhao
  • Liuhuan CAI
  • Xuechao Tian
  • Ming Sang
  • Chi Yuen Raymond Kwong
  • Chuanjun Xia

Assignees

  • Beijing Summer Sprout Technology Co., Ltd.

Dates

Publication Date
20260507
Application Date
20250925
Priority Date
20240925

Claims (20)

  1. 1 . An organic electroluminescent device, comprising: an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises at least a fluorescent material and a metal complex; wherein the fluorescent material has a structure represented by Formula 1: wherein in Formula 1, the ring A, the ring B, the ring C, the ring D, and the ring E are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms or an unsaturated heterocyclic ring having 3 to 30 carbon atoms; Y 1 is selected from B, P═O, P═S, As, As=O, As=S, SiR′, or GeR′; R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 represent, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; R′, R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof, and adjacent substituents R a1 , R a2 , R a3 , R a4 , R a5 , R a6 can be optionally joined to form a ring; wherein the metal complex comprises a metal M and a ligand L a coordinated to the metal M, the metal M is selected from a metal with a relative atomic mass greater than 40, and the ligand L a has a structure represented by Formula 2: wherein in Formula 2, the ring F and the ring G are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 1 to 30 carbon atoms, or a combination thereof; X 1 and X 2 are identically or differently selected from C or N; K 1 and K 2 are each independently selected from a single bond, O, or S; A 1 is selected from a single bond, O, S, Se, (SiR q R q ) y , PR q , NR q , (CR q R q ) y , substituted or unsubstituted arylene having 6 to 30 carbon atoms, substituted or unsubstituted heteroarylene having 3 to 30 carbon atoms, or a combination thereof, wherein y is, at each occurrence identically or differently, selected from 1, 2, 3, 4, or 5; R f and R g represent, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; R f and R g are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof, and adjacent substituents R f and R g can be optionally joined to form a ring.
  2. 2 . The organic electroluminescent device according to claim 1 , wherein the ring A, the ring B, the ring C, the ring D, and the ring E are each independently selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6 to 30 carbon atoms, or a heteroaromatic ring having 3 to 30 carbon atoms; preferably, the ring A, the ring B, the ring C, the ring D, and the ring E are, at each occurrence identically or differently, selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6 to 18 carbon atoms, or a heteroaromatic ring having 3 to 18 carbon atoms; more preferably, the ring A, the ring B, the ring C, the ring D, and the ring E are, at each occurrence identically or differently, selected from a benzene ring, a pyridine ring, a naphthalene ring, a phenanthrene ring, an anthracene ring, an indene ring, a fluorene ring, an indole ring, a carbazole ring, a benzofuran ring, a dibenzofuran ring, a benzosilole ring, a dibenzosilole ring, a benzothiophene ring, a dibenzothiophene ring, a dibenzoselenophene ring, a cyclopentadienyl ring, a furan ring, a thiophene ring, a silole ring, or a combination thereof.
  3. 3 . The organic electroluminescent device according to claim 1 , wherein the fluorescent material has a structure represented by Formula 1-1: wherein Y 1 is selected from B, P═O, P═S, As, As=O, As=S, SiR′, or GeR′; R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 represent, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; R′, R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; and adjacent substituents R a1 , R a2 , R a3 , R a4 , R a5 , R a6 can be optionally joined to form a ring; preferably, Y 1 is selected from B, P═O, or P═S; more preferably, Y 1 is selected from B.
  4. 4 . The organic electroluminescent device according to claim 3 , wherein R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, cyano, hydroxyl, sulfanyl, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, and combinations thereof; preferably, R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, cyano, hydroxyl, sulfanyl, substituted or unsubstituted alkyl having 1 to 6 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 6 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 6 ring atoms, substituted or unsubstituted aryl having 6 to 24 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 12 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 6 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 12 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 6 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 12 carbon atoms, substituted or unsubstituted amino having 0 to 12 carbon atoms, and combinations thereof; more preferably, R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, fluorine, cyano, hydroxyl, sulfanyl, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, t-butyl, cyclopentyl, neopentyl, cyclohexyl, trimethylsilyl, trimethylgermanyl, phenyl, biphenyl, terphenyl, tetraphenyl, triphenylenyl, tetraphenylenyl, naphthyl, phenanthryl, anthryl, indenyl, fluorenyl, indolyl, carbazolyl, benzofuryl, dibenzofuryl, benzosilolyl, dibenzosilolyl, benzothienyl, dibenzothienyl, dibenzoselenophenyl, diphenylamino, dibenzofurylphenylamino, and combinations thereof.
  5. 5 . The organic electroluminescent device according to claim 3 , wherein at least one of R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 is, at each occurrence identically or differently, selected from the group consisting of: deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; preferably, at least one of R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 is, at each occurrence identically or differently, selected from the group consisting of: deuterium, halogen, cyano, hydroxyl, sulfanyl, substituted or unsubstituted alkyl having 1 to 6 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 6 carbon atoms, substituted or unsubstituted aryl having 6 to 24 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 12 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 6 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 12 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 6 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 12 carbon atoms, substituted or unsubstituted amino having 0 to 12 carbon atoms, and combinations thereof, more preferably, at least one of R a1 , R a2 , R a3 , R a4 , R a5 , and R a6 is, at each occurrence identically or differently, selected from the group consisting of: deuterium, fluorine, cyano, hydroxyl, sulfanyl, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, t-butyl, cyclopentyl, neopentyl, cyclohexyl, trimethylsilyl, trimethylgermanyl, phenyl, biphenyl, terphenyl, tetraphenyl, triphenylenyl, tetraphenylenyl, naphthyl, phenanthryl, anthryl, indenyl, fluorenyl, indolyl, carbazolyl, benzofuryl, dibenzofuryl, benzosilolyl, dibenzosilolyl, benzothienyl, dibenzothienyl, dibenzoselenophenyl, diphenylamino, dibenzofurylphenylamino, and combinations thereof.
  6. 6 . The organic electroluminescent device according to claim 3 , wherein R a3 is selected from the group consisting of: substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, and combinations thereof, preferably, R a3 is selected from the group consisting of: substituted or unsubstituted aryl having 6 to 24 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 12 carbon atoms, and combinations thereof, more preferably, R a3 is selected from the group consisting of: phenyl, biphenyl, terphenyl, tetraphenyl, triphenylenyl, tetraphenylenyl, naphthyl, phenanthryl, anthryl, indenyl, fluorenyl, indolyl, carbazolyl, benzofuryl, dibenzofuryl, benzosilolyl, dibenzosilolyl, benzothienyl, dibenzothienyl, dibenzoselenophenyl, and combinations thereof.
  7. 7 . The organic electroluminescent device according to claim 3 , wherein R a4 is selected from the group consisting of: substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, and combinations thereof, preferably, R a4 is selected from the group consisting of: substituted or unsubstituted aryl having 6 to 24 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 12 carbon atoms, and combinations thereof, more preferably, R a4 is selected from the group consisting of: phenyl, biphenyl, terphenyl, tetraphenyl, triphenylenyl, tetraphenylenyl, naphthyl, phenanthryl, anthryl, indenyl, fluorenyl, indolyl, carbazolyl, benzofuryl, dibenzofuryl, benzosilolyl, dibenzosilolyl, benzothienyl, dibenzothienyl, dibenzoselenophenyl, and combinations thereof.
  8. 8 . The organic electroluminescent device according to claim 1 , wherein the fluorescent material is selected from the group consisting of Compound BD-1-1 to Compound BD-1-33, Compound BD-2-1 to Compound BD-2-19, Compound BD-3-1 to Compound BD-3-15, Compound BD-4-1 to Compound BD-4-36, and Compound BD-5-1 to Compound BD-5-14: wherein optionally, hydrogens in the structures of Compound BD-1-1 to Compound BD-1-33, Compound BD-2-1 to Compound BD-2-19, Compound BD-3-1 to Compound BD-3-15, Compound BD-4-1 to Compound BD-4-36, and Compound BD-5-1 to Compound BD-5-13 can be partially or fully substituted with deuterium.
  9. 9 . The organic electroluminescent device according to claim 1 , wherein a maximum emission wavelength λ max-PL-1 of a photoluminescence spectrum of the fluorescent material is 450 nm to 500 nm; preferably, the maximum emission wavelength λ max-PL-1 of the photoluminescence spectrum of the fluorescent material is 450 nm to 470 nm; more preferably, the maximum emission wavelength λ max-PL-1 of the photoluminescence spectrum of the fluorescent material is 455 nm to 465 nm.
  10. 10 . The organic electroluminescent device according to claim 1 , wherein a full width at half maximum FWHM- PL-1 of a photoluminescence spectrum of the fluorescent material is less than or equal to 45 nm; preferably, the full width at half maximum FWHM- PL-1 of the photoluminescence spectrum of the fluorescent material is less than or equal to 35 nm; more preferably, the full width at half maximum FWHM- PL-1 of the photoluminescence spectrum of the fluorescent material is less than or equal to 25 nm.
  11. 11 . The organic electroluminescent device according to claim 1 , wherein the metal complex has a general formula of M(L a ) m (L b ) n (L c ) q ; L a , L b , and L c are a first ligand, a second ligand, and a third ligand coordinated to the metal M, respectively; L a , L b , and L c are identical or different; the ligands L a , L b , and L c can be optionally joined to form a multidentate ligand; m is 1, 2, or 3, n is 0, 1, or 2, q is 0, 1, or 2, and m+n+q is equal to the oxidation state of the metal M; when m is greater than or equal to 2, multiple L a are identical or different; when n is 2, two L b are identical or different; when q is 2, two L c are identical or different; and the ligands L b and L c are, at each occurrence identically or differently, selected from a monoanionic bidentate ligand; preferably, the ligands L b and L c are, at each occurrence identically or differently, selected from the group consisting of the following structures: wherein R a and R b represent, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; X b is, at each occurrence identically or differently, selected from the group consisting of: O, S, Se, NR N1 , and CR C1 R C2 ; X c and X d are, at each occurrence identically or differently, selected from the group consisting of: O, S, Se, and NR N2 ; R a , R b , R c , R N1 , R N2 , R C1 , and R C2 are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; and adjacent substituents R, R b , R c , R N1 , R N2 , R C1 , and R C2 can be optionally joined to form a ring.
  12. 12 . The organic electroluminescent device according to claim 11 , wherein the metal M is selected from the group consisting of Cu, Ag, Au, Zn, Ru, Rh, Pd, Os, Ir, and Pt; preferably, the metal M is selected from Ir, Pt, or Pd.
  13. 13 . The organic electroluminescent device according to claim 11 , wherein the metal complex has a structure represented by Formula 3: wherein in Formula 3, the ring F, the ring G, the ring H, and the ring I are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 1 to 30 carbon atoms, or a combination thereof; f is selected from 0 or 1; A 1 to A 4 are, at each occurrence identically or differently, selected from a single bond, O, S, Se, (SiR q R q ) y , PR q , NR q , (CF q ) y , substituted or unsubstituted arylene having 6 to 30 carbon atoms, substituted or unsubstituted heteroarylene having 3 to 30 carbon atoms, or a combination thereof, wherein y is, at each occurrence identically or differently, selected from 1, 2, 3, 4, or 5; X 1 to X 4 are each independently selected from C or N; K 1 to K 4 are each independently selected from a single bond, O, or S; R n represents, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; R q and R n are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof, and adjacent substituents R q , R n can be optionally joined to form a ring.
  14. 14 . The organic electroluminescent device according to claim 13 , wherein the metal complex has a structure represented by Formula 3-A: wherein in Formula 3-A, the ring F, the ring G, and the ring H are each independently selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof, and the ring I is selected from an unsaturated heterocyclic ring having 1 to 30 carbon atoms; A 1 and A 4 are each independently selected from a single bond, O, S, Se, (SiR q R q ) y , PR q , NR q , (CR q R q ) y , substituted or unsubstituted arylene having 6 to 30 carbon atoms, substituted or unsubstituted heteroarylene having 3 to 30 carbon atoms, or a combination thereof, wherein y is, at each occurrence identically or differently, selected from 1, 2, 3, 4, or 5; K 1 to K 4 are each independently selected from a single bond, O, or S; X 1 to X 3 are each independently selected from C or N; R n represents, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; R, R q , and R n are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof, and adjacent substituents R, R q , R n can be optionally joined to form a ring.
  15. 15 . The organic electroluminescent device according to claim 14 , wherein the ring F, the ring G, and the ring H are each independently selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6 to 30 carbon atoms, or a heteroaromatic ring having 3 to 30 carbon atoms, and the ring I is, at each occurrence identically or differently, selected from an unsaturated heterocyclic ring having 3 to 30 carbon atoms; preferably, the ring F, the ring G, and the ring H are each independently selected from a five-membered unsaturated carbocyclic ring, an aromatic ring having 6 to 18 carbon atoms, or a heteroaromatic ring having 3 to 18 carbon atoms, and the ring I is, at each occurrence identically or differently, selected from an unsaturated heterocyclic ring having 3 to 18 carbon atoms; more preferably, the ring F, the ring G, and the ring H are each independently selected from a benzene ring, a pyridine ring, an indene ring, a fluorene ring, an indole ring, a carbazole ring, a benzofuran ring, a dibenzofuran ring, a benzosilole ring, a dibenzosilole ring, a benzothiophene ring, a dibenzothiophene ring, a dibenzoselenophene ring, a cyclopentadienyl ring, a furan ring, a thiophene ring, or a silole ring, and the ring I is, at each occurrence identically or differently, selected from an imidazole-carbene ring or a benzimidazole-carbene ring.
  16. 16 . The organic electroluminescent device according to claim 14 , wherein K 1 to K 4 are each selected from a single bond.
  17. 17 . The organic electroluminescent device according to claim 1 , wherein the metal complex has a structure represented by one of Formula 3-1 to Formula 3-20: wherein A 4 is, at each occurrence identically or differently, selected from a single bond, O, S, Se, (SiR q R q ) y , PR q , NR q , substituted or unsubstituted arylene having 6 to 30 carbon atoms, substituted or unsubstituted heteroarylene having 3 to 30 carbon atoms, or a combination thereof, wherein y is, at each occurrence identically or differently, selected from 1, 2, or 3; U 1 to U 28 are, at each occurrence identically or differently, selected from CR n or N; R u represents, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; R, R N , R q , R u , and R n are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof, and adjacent substituents R, R N , R q , R u , and R n can be optionally joined to form a ring; preferably, the metal complex has a structure represented by Formula 3-1 or Formula 3-2; more preferably, the substituent R has a structure represented by Formula 4: wherein in Formula 4, the ring M and the ring W are, at each occurrence identically or differently, selected from an unsaturated carbocyclic ring having 5 to 30 carbon atoms, an unsaturated heterocyclic ring having 3 to 30 carbon atoms, or a combination thereof; X 5 to X 8 are, at each occurrence identically or differently, selected from C or N; “*” represents a position where Formula 4 is joined; R m and R w represent, at each occurrence identically or differently, mono-substitution, multiple substitutions, or non-substitution; R m and R w are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof, and adjacent substituents R m , R w can be optionally joined to form a ring; most preferably, the substituent R has a structure represented by Formula 4-1: wherein in Formula 4-1, M 1 to M 10 are each independently selected from CR m or N; W 1 to W 3 are each independently selected from CR w or N; “**” represents a position where Formula 4-1 is joined; R m and R w are, at each occurrence identically or differently, selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, substituted or unsubstituted arylalkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkynyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl having 6 to 20 carbon atoms, substituted or unsubstituted alkylgermanyl having 3 to 20 carbon atoms, substituted or unsubstituted arylgermanyl having 6 to 20 carbon atoms, substituted or unsubstituted amino having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a cyano group, an isocyano group, a hydroxyl group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof; and adjacent substituents R m , R w can be optionally joined to form a ring.
  18. 18 . The organic electroluminescent device according to claim 1 , wherein the metal complex is selected from the group consisting of BD1 to BD18: or the metal complex has a structure represented by Pt(L a )(L b ), L a and L b are a first ligand and a second ligand coordinated to Pt, respectively, and L a is selected from the group consisting of L a 1-1 to L a 1-25 and L a 2-1 to L a 2-6: wherein “#” in the structures of L a 1-1 to L a 1-25 and L a 2-1 to L a 2-6 represents a position where L b is joined; L b is selected from the group consisting of L b 1-1 to L b 1-8 and L b 2-1 to L b 2-22: wherein “ ” in the structures of L b 1-1 to L b 1-8 and L b 2-1 to L b 2-22 represents a position where L a is joined, preferably, the metal complex is selected from the group consisting of Pt1 to Pt81, wherein Pt1 to Pt81 each have the structure represented by Pt(L a )(L b ), and L a and L b are selected from the structures shown in the following table, respectively: Metal Metal Complex No. L a L b Complex No. L a L b Pt1 L a 1-6 L b 1-1 Pt2 L a 1-6 L b 1-2 Pt3 L a 1-6 L b 1-3 Pt4 L a 1-6 L b 1-4 Pt5 L a 1-6 L b 1-5 Pt6 L a 1-6 L b 1-6 Pt7 L a 1-6 L b 1-7 Pt8 L a 1-6 L b 1-8 Pt9 L a 1-11 L b 1-1 Pt10 L a 1-11 L b 1-2 Pt11 L a 1-11 L b 1-3 Pt12 L a 1-11 L b 1-4 Pt13 L a 1-11 L b 1-5 Pt14 L a 1-11 L b 1-6 Pt15 L a 1-11 L b 1-7 Pt16 L a 1-11 L b 1-8 Pt17 L a 1-12 L b 1-1 Pt18 L a 1-12 L b 1-2 Pt19 L a 1-12 L b 1-3 Pt20 L a 1-12 L b 1-4 Pt21 L a 1-12 L b 1-5 Pt22 L a 1-12 L b 1-6 Pt23 L a 1-12 L b 1-7 Pt24 L a 1-12 L b 1-8 Pt25 L a 1-18 L b 1-1 Pt26 L a 1-18 L b 1-2 Pt27 L a 1-18 L b 1-3 Pt28 L a 1-18 L b 1-4 Pt29 L a 1-18 L b 1-5 Pt30 L a 1-18 L b 1-6 Pt31 L a 1-18 L b 1-7 Pt32 L a 1-18 L b 1-8 Pt33 L a 1-18 L b 2-1 Pt34 L a 1-18 L b 2-2 Pt35 L a 1-18 L b 2-3 Pt36 L a 1-18 L b 2-4 Pt37 L a 1-18 L b 2-5 Pt38 L a 1-18 L b 2-6 Pt39 L a 1-18 L b 2-7 Pt40 L a 1-18 L b 2-8 Pt41 L a 1-18 L b 2-9 Pt42 L a 1-18 L b 2-10 Pt43 L a 1-18 L b 2-11 Pt44 L a 1-18 L b 2-12 Pt45 L a 1-18 L b 2-13 Pt46 L a 1-18 L b 2-14 Pt47 L a 1-18 L b 2-15 Pt48 L a 1-18 L b 2-16 Pt49 L a 1-18 L b 2-17 Pt50 L a 1-18 L b 2-18 Pt51 L a 1-18 L b 2-19 Pt52 L a 1-18 L b 2-20 Pt53 L a 1-18 L b 2-21 Pt54 L a 1-18 L b 2-22 Pt55 L a 1-1 L b 1-3 Pt56 L a 1-2 L b 1-3 Pt57 L a 1-3 L b 1-3 Pt58 L a 1-4 L b 1-3 Pt59 L a 1-5 L b 1-3 Pt60 L a 1-7 L b 1-3 Pt61 L a 1-8 L b 1-3 Pt62 L a 1-9 L b 1-3 Pt63 L a 1-10 L b 1-3 Pt64 L a 1-13 L b 1-3 Pt65 L a 1-14 L b 1-3 Pt66 L a 1-15 L b 1-3 Pt67 L a 1-16 L b 1-3 Pt68 L a 1-17 L b 1-3 Pt69 L a 1-19 L b 1-3 Pt70 L a 1-20 L b 1-3 Pt71 L a 1-21 L b 1-3 Pt72 L a 1-22 L b 1-3 Pt73 L a 1-23 L b 1-3 Pt74 L a 1-24 L b 1-3 Pt75 L a 1-25 L b 1-3 Pt76 L a 2-1 L b 1-3 Pt77 L a 2-2 L b 1-3 Pt78 L a 2-3 L b 1-3 Pt79 L a 2-4 L b 1-3 Pt80 L a 2-5 L b 1-3 Pt81 L a 2-6 L b 1-3
  19. 19 . The organic electroluminescent device according to claim 1 , wherein the organic layer is an emissive layer and the metal complex is a phosphorescent sensitizer; preferably, the emissive layer comprises a first host compound and a second host compound; more preferably, the first host compound and the second host compound are each independently selected from a compound comprising at least one chemical group selected from the group consisting of: benzene, pyridine, pyrimidine, triazine, carbazole, azacarbazole, indolocarbazole, dibenzothiophene, aza-dibenzothiophene, dibenzofuran, azadibenzofuran, dibenzoselenophene, triphenylene, azatriphenylene, fluorene, silafluorene, naphthalene, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene, azaphenanthrene, and combinations thereof.
  20. 20 . A display apparatus, comprising the organic electroluminescent device according to claim 1 .

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) This application claims priority to Chinese Patent Application No. 202411344500.7 filed on Sep. 25, 2024, the disclosure of which is incorporated herein by reference in its entirety. TECHNICAL FIELD The present disclosure relates to organic electronic devices, for example, organic electroluminescent devices. More particularly, the present disclosure relates to an organic electroluminescent device with an organic layer comprising at least a metal complex and a fluorescent material. BACKGROUND Organic electronic devices include, but are not limited to, the following types: organic light-emitting diodes (OLEDs), organic field-effect transistors (O-FETs), organic light-emitting transistors (OLETs), organic photovoltaic devices (OPVs), dye-sensitized solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field-quench devices (OFQDs), light-emitting electrochemical cells (LECs), organic laser diodes and organic plasmon emitting devices. In 1987, Tang and Van Slyke of Eastman Kodak reported a bilayer organic electroluminescent device, which comprises an arylamine hole transporting layer and a tris-8-hydroxyquinolato-aluminum layer as the electron and emitting layer (Applied Physics Letters, 1987, 51 (12): 913-915). Once a bias is applied to the device, green light was emitted from the device. This device laid the foundation for the development of modern organic light-emitting diodes (OLEDs). State-of-the-art OLEDs may comprise multiple layers such as charge injection and transporting layers, charge and exciton blocking layers, and one or multiple emissive layers between the cathode and anode. Since the OLED is a self-emitting solid state device, it offers tremendous potential for display and lighting applications. In addition, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications such as fabrication on flexible substrates. The OLED can be categorized as three different types according to its emitting mechanism. The OLED invented by Tang and van Slyke is a fluorescent OLED. It only utilizes singlet emission. The triplets generated in the device are wasted through nonradiative decay channels. Therefore, the internal quantum efficiency (IQE) of the fluorescent OLED is only 25%. This limitation hindered the commercialization of OLED. In 1997, Forrest and Thompson reported phosphorescent OLED, which uses triplet emission from heavy metal containing complexes as the emitter. As a result, both singlet and triplets can be harvested, achieving 100% IQE. The discovery and development of phosphorescent OLED contributed directly to the commercialization of active-matrix OLED (AMOLED) due to its high efficiency. Recently, Adachi achieved high efficiency through thermally activated delayed fluorescence (TADF) of organic compounds. These emitters have small singlet-triplet gap that makes the transition from triplet back to singlet possible. In the TADF device, the triplet excitons can go through reverse intersystem crossing to generate singlet excitons, resulting in high IQE. OLEDs can also be classified as small molecule and polymer OLEDs according to the forms of the materials used. A small molecule refers to any organic or organometallic material that is not a polymer. The molecular weight of the small molecule can be large as long as it has well defined structure. Dendrimers with well-defined structures are considered as small molecules. Polymer OLEDs include conjugated polymers and non-conjugated polymers with pendant emitting groups. Small molecule OLED can become the polymer OLED if post polymerization occurred during the fabrication process. There are various methods for OLED fabrication. Small molecule OLEDs are generally fabricated by vacuum thermal evaporation. Polymer OLEDs are fabricated by solution process such as spin-coating, inkjet printing, and slit printing. If the material can be dissolved or dispersed in a solvent, the small molecule OLED can also be produced by solution process. The emitting color of the OLED can be achieved by emitter structural design. An OLED may comprise one emitting layer or a plurality of emitting layers to achieve desired spectrum. In the case of green, yellow, and red OLEDs, phosphorescent emitters have successfully reached commercialization. Blue phosphorescent device still suffers from non-saturated blue color, short device lifetime, and high operating voltage. Commercial full-color OLED displays normally adopt a hybrid strategy, using fluorescent blue and phosphorescent yellow, or red and green. At present, efficiency roll-off of phosphorescent OLEDs at high brightness remains a problem. In addition, it is desirable to have more saturated emitting color, higher efficiency, and longer device lifetime. WO2020251049A1 has disclosed a fused ring compound having a general formula of and further disclosed a secondary general formula of wherein X is