The present application relates to materials for use in electronic devices, to processes for preparing the materials, and to electronic devices containing the materials.

An organic electroluminescent device and a display apparatus. The organic electroluminescent device includes a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode, where the organic layer includes an emission layer (EML), the EML includes a host material, a thermally activated delayed fluorescence (TADF) sensitizer and a fluorescent dye, and the fluorescent dye is selected from a compound represented by Formula (1).

The present invention relates to an organic light emitting diode comprising a substrate, an anode, a cathode, an emission layer, an electron injection layer and an electron transport layer stack; and to a display device or lighting device comprising the same.

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 of Formula I ##STR00001## wherein at least one of R.sup.1 or R.sup.2 includes a polycyclic group selected from the group consisting of Formula A, Formula B, and Formula C: ##STR00002##
wherein X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are independently CR.sup.A or N; X.sup.5, X.sup.6, X.sup.7, and X.sup.8 are independently CR.sup.B or N; X.sup.9, X.sup.10, X.sup.11, and X.sup.12 are independently CR.sup.C or N; X.sup.13, X.sup.14, X.sup.15, and X.sup.16 are independently CR.sup.D or N; X.sup.17, X.sup.18, X.sup.19, and X.sup.20 are independently CR.sup.E or N; X.sup.21, X.sup.22, X.sup.23, and X.sup.24 are independently CR.sup.F or N; X.sup.25, X.sup.26, X.sup.27, and X.sup.28 are independently CR.sup.G or N; X.sup.29, X.sup.30, X.sup.31, and X.sup.32 are independently CR.sup.H or N; Y is selected from the group consisting of O, S, NR, and CRR′; the maximum number of N atoms that can connect to each other within each ring is two; with the proviso that R.sup.1 does not connect to ring B, and R.sup.2 does not connect to ring A, and wherein at least one of R.sup.C and R.sup.D of Formula A is a direct bond or an organic linker, one of R.sup.E and R.sup.F of Formula B is a direct bond or an organic linker, or one of R.sup.G, R.sup.H, and R.sup.N of Formula C is a direct bond or an organic linker.

An organic light-emitting device having low-driving voltage, improved efficiency, and long lifespan includes: a first electrode; a second electrode facing the first electrode; a first layer between the first electrode and the second electrode, the first layer including a first compound; a second layer between the first layer and the second electrode, the second layer including a second compound; and a third layer between the second layer and the second electrode, the third layer including a third compound; wherein the first compound does not include a nitrogen-containing heterocyclic group comprising *═N—*′ as a ring forming moiety, and wherein the first compound, the second compound, and the third compound each independently include at least one group selected from groups represented by Formulae A to C:

##STR00001##

Provided is a light-emitting element including a fluorescence-emitting material with high emission efficiency. The light-emitting element includes a pair of electrodes and an EL layer between the pair of electrodes. The EL layer includes a first organic compound, a second organic compound, and a guest material. The first organic compound has a function of emitting a thermally activated delayed fluorescence at room temperature. The guest material has a function of emitting fluorescence. A HOMO level of the first organic compound higher than or equal to a HOMO level of the second organic compound. A LUMO level of the first organic compound is lower than or equal to a LUMO level of the second organic compound.

The present disclosure relates to an organic electroluminescent compound and an organic electroluminescent device comprising the same. The organic electroluminescent device with improved driving voltage and/or power efficiency can be provided by using the organic electroluminescent compound according to the present disclosure.

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).

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).