An organic compound and an organic light emitting device including the same are disclosed. For example, an organic compound is represented by the following chemical formula in which one of X1 and X2 is N, and the other one of X1 and X2 is O or S. The organic light emitting diode and the organic light emitting device each includes the organic compound.

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A solar cell, a preparation method for a solar cell, and a photovoltaic module, relating to the technical field of solar energy photovoltaics. The solar cell includes a crystalline silicon cell unit, and a down-conversion luminescence layer and a perovskite layer sequentially located on the light-facing surface of the crystalline silicon cell unit. The band gap of the perovskite layer becomes gradually smaller in the direction from the light-facing surface to the back surface. The band gap at the back surface of the perovskite layer is greater than or equal to the band gap of an absorption layer of the crystalline silicon cell unit. Because the band gap gradually decreases from large to small, the perovskite layer features a wide absorption spectrum, a long charge carrier free path, higher luminous efficiency, thus being able to broaden the spectral absorption range of the solar cell, and improve energy use and conversion efficiency. The complex processing of multi-layer battery superposition is avoided, the multiple film layer structure is simplified, losses in transmission of charge carriers between film layer interfaces and series structures are avoided, the conversion efficiency of the solar cell is further improved, and the processing difficulty is reduced, facilitating industrial production.

A method of forming a light emitting diode array comprising a plurality of light emitting pixels, wherein at least one of the light emitting pixels comprises: a light emitting diode configured to emit light of a first primary peak wavelength; a first region comprising a first down conversion material configured to receive and convert input light of the first primary peak wavelength from the light emitting diode to provide output light of a second primary peak wavelength and unconverted light of the first primary peak wavelength; and a second region comprising organic semiconductor material dispersed in a medium, the organic semiconductor material configured to absorb input light of the first primary peak wavelength, wherein the second region is configured to transmit output light of the second primary peak wavelength from the first region and absorb unconverted light of the first primary peak wavelength passing from the light emitting diode through the second region, thereby to increase the light colour purity emitted by the at least one light emitting pixel.

The present disclosure provides an energy down-conversion system that receives energy from the outside and converts it into low energy, including a multifunctional emitting compound.

An organic light-emitting device which including a first electrode, a second electrode facing the first electrode, and an emission layer disposed between the first electrode and the second electrode, wherein an emission layer includes a first material, a second material, and a third material satisfying certain conditions.

Arrangements for phosphorescent blue emissive materials, layers, and devices are provided. The arrangements include a host having first a triplet energy level of at least 2.8 eV and an absolute difference of not more than 0.3 eV between the first singlet and triplet energy levels, and an emitter that includes an emissive transition metal complex and a first triplet energy level of at least 2.7 eV.

A light-emitting element with high emission efficiency which includes fluorescent materials is provided. The light-emitting element includes a first light-emitting layer and a second light-emitting layer. The first light-emitting layer includes a first fluorescent material and a first host material, and the second light-emitting layer includes a second fluorescent material and a second host material. The second host material includes a first organic compound and a second organic compound. The first organic compound and the second organic compound form an exciplex. A singlet excited energy level of the first host material is higher than a singlet excited energy level of the first fluorescent material, and a triplet excited energy level of the first host material is lower than a triplet excited energy level of the first fluorescent material.

A light-emitting element with high emission efficiency which includes fluorescent materials is provided. The light-emitting element includes a first light-emitting layer and a second light-emitting layer. The first light-emitting layer includes a first fluorescent material and a first host material, and the second light-emitting layer includes a second fluorescent material and a second host material. The second host material includes a first organic compound and a second organic compound. The first organic compound and the second organic compound form an exciplex. A singlet excited energy level of the first host material is higher than a singlet excited energy level of the first fluorescent material, and a triplet excited energy level of the first host material is lower than a triplet excited energy level of the first fluorescent material.

Compositions and mechanisms for the transfer of spin-triplet excitons from a singlet exciton fission material (e.g., tetracene) to an inorganic semiconductor (e.g., n-doped silicon) are provided. The compositions include one or more interlayers, including a charge transfer interlayer (e.g., zinc phthalocyanine), and, optionally, a passivation interlayer (e.g., hafnium oxide, HfO.sub.2). The triplet transfer mechanism proceeds via the formation of a charge transfer intermediate state. The transition to the intermediate state is energetically favored by strategically positioned HOMO and/or LUMO levels of the charge transfer interlayer between the singlet fission layer and the inorganic semiconductor. The intermediate state is formed through a transition of either the electron or the hole of the triplet exciton in the charge transfer interlayer (depending, at least in part, on the relative positions of the energy levels) to the conduction or valence band of the inorganic semiconductor, respectively. Methods of forming the compositions are also disclosed.

The present invention relates to a formulation comprising organic materials for the production of organic electronic devices having a low failure rate.