A wavelength conversion member including a wavelength conversion layer containing a fluoride phosphor, quantum dots, a surfactant, and a resin. The fluoride phosphor contains fluoride particles having a specific composition and having particle size values within specific ranges. The quantum dots include at least one selected from a first crystalline nanoparticle and a second crystalline nanoparticle. The first crystalline nanoparticle has a specific composition. When irradiated with light having a wavelength of 450 nm, the first crystalline nanoparticle emits light having an emission peak at a wavelength in a range from 510 nm to 535 nm, and a full width at half maximum of the emission peak of the first crystalline nanoparticle is in a range from 10 nm to 30 nm. The second crystalline nanoparticle includes a chalcopyrite-type crystalline structure, and a full width at half maximum of the emission peak of the second crystalline nanoparticle is 45 nm or less.

A ligand includes a molecular skeleton, a first coordinating group connected to the molecular skeleton, at least one initial group connected to the molecular skeleton, and a protecting group connected to an end of each initial group away from the molecular skeleton. Each initial group is capable of forming a second coordinating group after deprotection.

The present invention relates to a light emitting device including a light emitting layer having a stacked structure of two or more layers in which the light emitting layer is alternately disposed with a first light emitting material layer and a second light emitting material layer. In addition, the light-emitting material layer is a perovskite layer or an organic material layer, the first light-emitting material layer and the second light-emitting material layer are characterized in that they have different band gaps. By alternately disposing the first light emitting material layer and the second light emitting material layer to have a stacked structure and by controlling the energy level, there is an advantage in that the electroluminescence efficiency can be improved by controlling the electron-hole recombination region of the light emitting device. In addition, there is an advantage that a white light emitting device can be manufactured by controlling the energy levels of the first light emitting material layer and the second light emitting material layer.

A light-receiving device that is highly convenient, useful, or reliable is provided. The light-receiving device includes a light-receiving layer between a pair of electrodes, the light-receiving layer includes an active layer and a hole-transport layer, the hole-transport layer contains a first organic compound, and the first organic compound is an aromatic monoamine compound or a heteroaromatic monoamine compound having at least one skeleton of biphenylamine, carbazolylamine, dibenzofuranylamine, dibenzothiophenylamine, fluorenylamine, and spirofluorenylamine. Alternatively, the light-receiving device includes a light-receiving layer between a pair of electrodes, the light-receiving layer includes an electron-transport layer and an active layer, the electron-transport layer contains a second organic compound, and the second organic compound includes a triazine ring.

An organic compound is disclosed comprising: a first chemical moiety with a structure of formula I

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and two second chemical moieties, independently from another with a structure of formula II,

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wherein the first chemical moiety is linked to each of the two second chemical moieties via a single bond.

Stable perovskite films having substantially-no phase transition within a predetermined temperature range are disclosed. In the films, formation of carrier traps is suppressed. Thermally stable perovskite solar cells and light-emitting devices using the films are also disclosed.

The disclosure discloses an OLED element, a display panel, and a display device. The OLED element includes an anode, a light-emitting layer, a cathode stacked, and at least one of following components: an electric charge transfer and hole transmission component located between the anode and the light-emitting layer, where the electric charge transfer and hole transmission component includes a first light-induced electron transfer material and a hole transmission material; or an electric charge transfer and electron transmission component located between the cathode and the light-emitting layer, where the electric charge transfer and electron transmission component includes a second light-induced electron transfer material and an electron transmission material.

Disclosed herein is a polymeric film, the film comprising a polymeric matrix material, a plurality of perovskite nanocrystals and/or aggregates of perovskite nanocrystals dispersed throughout the polymeric matrix material. There is also disclosed a perovskite polymer resin composition, a perovskite-polymer resin composition, a perovskite ink and a method of forming a luminescent film using any one of the compositions or ink. Preferably, the perovskite material is a lead halide perovskite containing a cation selected from Cs, an alkylammonium ion, or a formamidinium ion. The polymeric matrix is preferably formed from monomers comprising a vinyl or an acrylate group.

Provided is an organic light-emitting device including: an anode; a cathode provided to face the anode; and organic material layers including a light emitting layer disposed between the anode and the cathode, wherein the light emitting layer, one or more layers of the organic material layers disposed between the anode and the light emitting layer, and one or more layers from among the organic material layers disposed between the cathode and the light emitting layer, each include one or more compounds each composed of sp3 carbon as a center, the light emitting layer includes a host including one or more anthracene-based compounds, and among organic materials included in the organic material layers, the bandgap energy (E.sub.bg) of each of the organic materials except for a dopant compound is 3 eV or more.

An organic electroluminescence device includes: an anode; a cathode; a first emitting layer; and a second emitting layer provided between the first emitting layer and the cathode, in which the first emitting layer contains, as a first host material, a first compound that has at least one group represented by a formula (11) below and that is represented by a formula (1) below, the second emitting layer contains, as a second host material, a second compound represented by one of formulae (2-1A) to (2-4A) below, and the first emitting layer and the second emitting layer are in direct contact with each other.

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