A light-emitting element containing a light-emitting material with high light emission efficiency is provided. The light-emitting element includes a high molecular material and a guest material. The high molecular material includes at least a first high molecular chain and a second high molecular chain. The guest material has a function of exhibiting fluorescence or converting triplet excitation energy into light emission. The first high molecular chain and the second high molecular chain each include a first skeleton, a second skeleton, and a third skeleton, and the first skeleton and the second skeleton are bonded to each other through the third skeleton. The first high molecular chain and the second high molecular chain have a function of forming an excited complex.

An organic molecule that may be used application in optoelectronic devices is disclosed. The organic molecule has a structure of formula 1, wherein R.sup.I, R.sup.II, R.sup.III, R.sup.IV, R.sup.V, R.sup.VI, R.sup.VII, R.sup.A, R.sup.B, R.sup.C, R.sup.D, R.sup.E, R.sup.F, R.sup.G and R.sup.H are independently selected from the group consisting of: hydrogen, deuterium, halogen, C.sub.1-C.sub.12-alkyl, wherein optionally one or more hydrogen atoms are independently substituted by R.sup.5; C.sub.6-C.sub.18-aryl, wherein optionally one or more hydrogen atoms are independently substituted R.sup.5; and C.sub.3-C.sub.15-heteroaryl, wherein optionally one or more hydrogen atoms are independently substituted R.sup.5; optionally, any adjacent two of R.sup.I, R.sup.II, R.sup.III, R.sup.IV, R.sup.V, R.sup.VI, R.sup.VII, R.sup.A, R.sup.B, R.sup.C, R.sup.D, R.sup.E, R.sup.F, R.sup.G and R.sup.H form a monocyclic ring system having 5 to 8 C-atoms, at least R.sup.A and R.sup.B as well as R.sup.C and R.sup.D form a monocyclic ring system having 5 to 8 C-atoms, wherein, optionally, each hydrogen is independently substituted.

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A light-emitting device includes a first electrode, a second electrode and a light-emitting layer arranged between the first electrode and the second electrode. The light-emitting layer includes a thermally activated delayed fluorescence (TADF) material, and the TADF material includes a donor, an acceptor, and a linking group connected between the donor and the acceptor. The donor includes a donor base unit, and a substituent connected to the donor base unit, and atoms in the donor base unit are located in a first plane. The acceptor includes an acceptor base unit, and a substituent connected to the acceptor base unit, and atoms in the acceptor base unit are located in a second plane. The linking group includes a linking base unit, and a substituent connected to the linking base unit, and atoms in the linking base unit are located in a third plane.

An organic electroluminescent device and a display apparatus. The organic electroluminescent device includes a first electrode, a second electrode and at least two organic electroluminescent units located between the first electrode and the second electrode. The at least two organic electroluminescent units are arranged in a stacked manner. The at least two organic electroluminescent units include a first organic electroluminescent unit. The first organic electroluminescent unit includes a first light-emitting layer. The first light-emitting layer contains a first host material, a thermally activated delayed fluorescence sensitizer and a first fluorescent dye.

The embodiments of the present disclosure provide a light-emitting device and a display substrate, which belong to the technical field of organic light-emitting diodes. The light-emitting device of the present disclosure comprises: a first light-emitting layer comprising a first host material and a first guest material; and a second light-emitting layer comprising a second host material and a second guest material; S1(h1)>S1(g1), T1(h1)>T1(g1), S1(g1)−T1(g1)≤0.1 eV; S1(h2)>S1(g2), T1(h2)>T1(g2), S1(g2)−T1(g2)≤0.1 eV; S1(h1)≥S1(h2)>S1(g1)>S1(g2), T1(h1)≥T1(h2)>T1(g1)>T1(g2); the second guest material is a TADF material; at least 40% of the area in a region covered under the emission spectrum of the first light-emitting layer overlaps with the region covered under the absorption spectrum of the second light-emitting layer.

The present invention relates to a boron hydroxyl-containing organic compound having a structural formula shown in formula I. The present invention also relates to a method for preparing the boron hydroxyl-containing organic compound and use thereof in an organic electronic device, particularly an organic light-emitting diode. The present invention further relates to an organic electronic device, particularly an organic light-emitting diode, including the boron hydroxyl-containing organic compound according to the present invention and use thereof in display and lighting technology. By optimizing the structure of the device and altering the concentration of the boron hydroxyl-containing organic compound in the substrate, the optimal device performance can be achieved so as to produce an OLED device with high efficiency, high brightness and high stability, which provides a better material option for use in full-color display and lighting.

A novel light-emitting device that is highly convenient, useful, or reliable is provided. The light-emitting device includes a first electrode, a second electrode, a unit, and a first layer. The second electrode includes a region overlapping with the first electrode. The unit includes a region positioned between the first electrode and the second electrode. The unit includes a second layer and a third layer. The second layer includes a region where the third layer is positioned between the second layer and the first electrode. The second layer contains a light-emitting material. The first layer includes a region positioned between the third layer and the first electrode. The first layer contains a material having an acceptor property and a first material. The first layer includes a first region and a second region. The first region includes a region positioned between the second region and the first electrode. The first region contains the material having an acceptor property at a first concentration. The second region contains the material having an acceptor property at a second concentration. Note that the second concentration is higher than zero and lower than the first concentration.

An electroluminescent device and a display device including the same. The electroluminescent device includes a first electrode and a second electrode facing each other; a light emitting layer disposed between the first electrode and the second electrode, the light emitting layer including a quantum dot; a hole transport layer disposed between the light emitting layer and the first electrode; and an electron transport layer disposed between the light emitting layer and the second electrode, wherein the hole transport layer, the light emitting layer, or a combination thereof includes thermally activated delayed fluorescence material, and the thermally activated delayed fluorescence material is present in an amount of greater than or equal to about 0.01 wt % and less than about 10 weight percent (wt %), based on 100 wt % of the hole transport layer, the light emitting layer, or the combination thereof including the thermally activated delayed fluorescence material.

The present disclosure relates to an organic light emitting diode that includes a first electrode; a second electrode facing the first electrode; and a first emitting material layer including a first compound and a second compound and positioned between the first and second electrodes, wherein an overlap ratio between an absorption spectrum of the first compound and an emission spectrum of the second compound is equal to or greater than 35%, and an organic light emitting display including the organic light emitting diode.

An organic light-emitting device including: a first electrode and a second electrode each having a surface opposite the other; and an intermediate layer disposed between the first electrode and the second electrode, the intermediate layer including a first compound and a second compound, wherein the first compound includes a first silyl group-containing group and at least two carbazole-derived groups, wherein one carbazole-derived group of the at least two carbazole-derived groups is bonded via a N atom to another carbazole-derived group, the second compound includes a second silyl group-containing group, a triazine group, and a carbazole-derived group, and at least one of the first compound or the second compound has a triplet (T.sub.1) energy level of 2.81 eV or more.