The present invention relates to the field of display technologies, and particularly to a fused polycyclic compound, a preparation method and use thereof. The fused polycyclic compound provided in the present invention has a structure of General Formula IV. The structure of the compound has ambipolarity, and the HOMO level and the LUMO level of the host material are respectively located on different electron donating group and electron withdrawing group, such that the transport of charges and holes in the host material becomes more balanced, thereby expanding the area where holes and electrons are recombined in the light emitting layer, reducing the exciton concentration, preventing the triplet-triplet annihilation of the device, and improving the efficiency of the device.

A compound including a bidentate ligand L.sub.A comprising a structure of Formula I,

##STR00001##

is disclosed. In Formula I, ring A′ is a 7-, 8-, or 9-membered ring structure; X is of NR.sup.2, O, CR, CRR′, S, or SiRR′; each of R.sup.A′, R.sup.1, and R.sup.2 is independently hydrogen or a substituent; R.sup.1′ is independently absent or a hydrogen or a substituent; any two adjacent R.sup.A′, R.sup.1, R.sup.1′, and R.sup.2 can be joined or fused to form a ring; the ligand L.sub.A is coordinated to a metal, which is selected from Os, Ir, Pd, Pt, Cu, Ag, or Au; and (1) at least one of R.sup.1 and R.sup.2 is coordinated to the metal M, or (2) at least one R.sup.A′ comprises a 5- or 6-membered carbocyclic or heterocyclic ring that is not directly fused to Ring A′ and is coordinated to the metal M, or both (1) and (2) are true. Formulations, devices, and consumer products including the compound are also disclosed.

A light-emitting device including a first electrode, a hole transport region disposed on the first electrode, a first light-emitting layer disposed on the hole transport region and emitting light of a first wavelength, a second light-emitting layer disposed on the hole transport region and emitting light of a second wavelength different from the first wavelength, an electron transport region disposed on the first light-emitting layer and the second light-emitting layer, and a second electrode disposed on the electron transport region, wherein the second light-emitting layer includes a first sub light-emitting layer including a first host and a first dopant and emitting the light of the second wavelength, and a second sub light-emitting layer including a second host different from the first host and a second dopant and emitting the light of the second wavelength. Accordingly, a luminous efficiency and device lifetime of the light-emitting device may be improved.

Provided are boron substituted organometallic compounds of Formula I:

##STR00001##

Also provided are formulations including these organometallic compounds. Further provided are OLEDs and related consumer products that utilize these organometallic compounds.

An organic light-emitting device including a first electrode, a second electrode facing the first electrode, and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer includes an emission layer, wherein the emission layer includes an electron transport host, a hole transport host, and a dopant, wherein the dopant includes an organometallic compound, and wherein the organometallic compound does not comprise iridium, wherein the organic light-emitting device satisfies predetermined parameters described in the specification.

Provided are an organic electronic element and an electronic device thereof, the organic electronic element being capable of achieving high light-emitting efficiency and a low driving voltage, and can also greatly improve the lifespan of the element by using a compound of the present invention as a phosphorescent host material.

The present invention relates to a compound of formula (I) and an organic electronic device comprising a semiconductor layer which comprises a compound of formula (I).

A composite material with a low refractive index that can be used for a light-emitting device, a light-receiving device, a light-emitting and light-receiving device, and the like is provided. The composite material includes a first organic compound and a second organic compound, the proportion of carbon atoms forming bonds by the sp.sup.3 hybrid orbitals in the total number of carbon atoms of the first organic compound is greater than or equal to 23% and less than or equal to 55%, and the second organic compound contains fluorine. Alternatively, an optical device including an anode, a cathode, and a first layer, in which the composite material is included in the first layer, is provided.

Embodiments provide a cyclic compound, a light-emitting device including the cyclic compound, and an electronic apparatus including the light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, an interlayer between the first electrode and the second electrode and including an emission layer; and at least one cyclic compound. The cyclic compound is represented by Formula 1:

##STR00001##

The description of Formula 1 is provided in the specification.

An organic light emitting display device is discussed, which includes an anode on a substrate, a first hole transfer layer on the anode, a first emission layer on the first hole transfer layer, a first electron transfer layer on the first emission layer, an N-type charge generation layer on the first electron transfer layer, a second hole transfer layer on the N-type charge generation layer, a first emission control layer on the second hole transfer layer, an absolute value of a highest occupied molecular orbital (HOMO) energy level of the first emission control layer being greater than an absolute value of a HOMO energy level of the second hole transfer layer, a second emission layer on the first emission control layer, a second electron transfer layer on the second emission layer and a cathode on the second electron transfer layer.