An electroluminescent device, a method for fabricating the same, a display panel, and a display device are disclosed. The electroluminescent device includes a hole inject layer, a hole transport layer, an electron transport layer, and an electron inject layer. At least one of the hole inject layer, the hole transport layer, the electron transport layer, and electron inject layer is a target film including a small molecular layer and a large molecular layer which are arranged in a stacked manner.

An organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; m emission units stacked between the first electrode and the second electrode, each emission unit including at least one emission layer; and m−1 charge generating layers respectively located between two adjacent emission units among them emission units, each of the charge generating layers including one n-type charge generating region and one p-type charge generating region, wherein m is an integer of 2 or more, and at least one of the m−1 p-type charge generating regions includes a phosphate-containing compound.

A light emitting device includes a first electrode, a hole transport region disposed on the first electrode, an emission layer disposed on the hole transport region, an electron transport region disposed on the emission layer, and a second electrode disposed on the electron transport region. The emission layer includes a fused polycyclic compound represented by Formula 1.

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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, and a first unit. The first unit is located between the first electrode and the second electrode, and the first unit has a function of emitting light. The first unit contains a light-emitting organic compound and an organic compound HRM. The organic compound HRM has four or more rotatable bonds and a principal moment of inertia. The principal moment of inertia includes a first normalized principal moment of inertia NPR1 and a second normalized principal moment of inertia NPR2 in a predetermined region.

An organic light-emitting device includes a first electrode, a second electrode facing the first electrode, an emission layer between the first electrode and the second electrode, and a hole transport region between the first electrode and the emission layer. The emission layer includes a first compound represented by Formula 1, and the hole transport region includes a second compound represented by Formula 2: ##STR00001##

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.

A light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode. The interlayer includes an emission layer and a hole transport layer between the first electrode and the emission layer. The emission layer includes a first host, a second host, and a dopant, wherein the first host includes a hole-transporting host, and the second host includes an electron-transporting host or a bipolar host. The hole transport layer includes multiple hole transport layers, the hole transport layers each include a carbazole-based compound, and highest occupied molecular orbital (HOMO) energy levels of the carbazole-based compounds respectively included in neighboring ones of the hole transport layers are different from each other.

To provide a compound for further improving the capability of an organic EL device, an organic electroluminescent element having a further improved device capability, and an electronic device including the organic electroluminescent element. Disclosed are a compound represented by the following formula (1) or formula (2) (wherein each symbol in each formula is as defined in the description), an organic electroluminescent element containing the compound, and an electronic device including the organic electroluminescent element.

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Provided are a compound for an organic optoelectronic device represented by a combination of Chemical Formula 1 and Chemical Formula 2, a composition for an organic optoelectronic device including the same, an organic optoelectronic device, and a display device. Details for Chemical Formula 1 and Chemical Formula 2 are as defined in the specification.

The present invention relates to a light-emitting device and an electronic apparatus including the light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode and including an emission layer, wherein: the interlayer may further include a hole transport region between the emission layer and the first electrode, the hole transport region may include a first layer and a second layer, the second layer being between the first layer and the emission layer, the first layer may include a first amine-based compound, the second layer may include a second amine-based compound, and the first amine-based compound and the second amine-based compound may be different from each other.