A light-emitting device with high resistance to heat in a fabrication process is provided. The light-emitting device includes an EL layer between an anode and a cathode. The EL layer includes at least a light-emitting layer and an electron-transport layer that includes a first electron-transport layer in contact with the light-emitting layer and a second electron-transport layer in contact with the first electron-transport layer. The first electron-transport layer includes a first heteroaromatic compound including at least one heteroaromatic ring. The second electron-transport layer includes a second heteroaromatic compound that includes at least one heteroaromatic ring and is different from the first heteroaromatic compound. The first heteroaromatic compound has a difference of 20° C. or less between the crystallization temperature (Tpc) of a powder state and the crystallization temperature (Ttc) of a thin film state. The second heteroaromatic compound has a difference of 100° C. or less between Tpc and Ttc.

There is provided an organic EL device, including: an anode; a cathode; an emitting layer provided between the anode and the cathode; a first layer provided between the anode and the emitting layer; and a second layer provided between the anode and the first layer, in which the emitting layer contains a delayed fluorescent compound, the first layer contains a first compound, the second layer contains a second compound, an ionization potential Ip(HT1) of the first compound satisfies Numerical Formula 1, a hole mobility μh(HT1) of the first compound satisfies Numerical Formula 2, an ionization potential Ip(HT2) of the second compound satisfies Numerical Formula 3, and the first layer has a film thickness of 15 nm or more,

Ip(HT1)≥5.69 eV  (Numerical Formula 1)

μh(HT1)≥1.00×10.sup.−5 cm.sup.2/Vs  (Numerical Formula 2)

Ip(HT2)≥5.60 eV  (Numerical Formula 3).

Organic electroluminescent materials and devices are disclosed. The organic electroluminescent materials are novel benzodithiophene or its analogous structure compounds, which can be used as charge transporting materials, hole injection materials, or the like in an electroluminescent device. These novel compounds can offer excellent performance compared with existing materials, for example, to further improve the voltage, efficiency and/or lifetime of the OLEDs.

A compound may improve the capability of an organic EL device, and an organic electroluminescent device including such compound may have improved capability and may be included in electronic devices. Such compounds may be of formula (1A) or formula (1B) (wherein the symbols are as defined in the description)

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organic electroluminescent device(s) may contain such compound(s), and electronic device(s) may include such organic electroluminescent device(s).

A photoelectric conversion element includes a base, a first electrode on or above the base, an electron-transporting layer on or above the first electrode, a photoelectric conversion layer on or above the electron-transporting layer, a hole-transporting layer on or above the photoelectric conversion layer, and a second electrode on or above the hole-transporting layer. The photoelectric conversion element has a penetration portion penetrating the electron-transporting layer and the photoelectric conversion layer. The photoelectric conversion element includes, in the penetration portion, a material of the hole-transporting layer and a material of the second electrode.

The present invention relates to a compound represented by formula 1, an organic optoelectronic element comprising the same, and a display device comprising the organic optoeletric element. Formula 1 and the description regarding the samen are as defined in the specification.

An organic light-emitting device includes: an anode, an emitting layer, and a cathode that are stacked; a first functional material layer located between the emitting layer and the anode; and a second functional material layer located between the emitting layer and the cathode. Under a same test condition, a hole mobility of a material of the first functional material layer is at least ten times an electron mobility of a material of the second functional material layer.

A light emitting element of an embodiment includes a first electrode, a second electrode, and at least one functional layer disposed between the first electrode and the second electrode and including an amine compound represented by Formula 1 below, thereby showing high efficiency and long-life characteristics.

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A light emitting device that includes a first electrode, a second electrode oppositely disposed to the first electrode, and an emission layer between the first electrode and the second electrode is provided. The emission layer includes an organometallic compound represented by Formula 1:

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A light emitting device that includes a first electrode, a second electrode facing the first electrode, and an emission layer between the first electrode and the second electrode is provided. The emission layer includes a first compound represented by Formula 1, and at least one of a second compound represented Formula H-1, a third compound represented Formula H-2, or a fourth compound represented Formula D-2, thereby exhibiting improved luminous efficiency characteristics.