Semiconductor Energy Laboratory Co., Ltd.

Tatsuyoshi Takahashi

Satoshi Seo

Hiromi Seo

Hideko Inoue

Takahiro Ishisone

Hiroki Suzuki

Hiromitsu Kido

Tomoya Yamaguchi

Miki Kanamoto

Yasushi Kitano

Sachiko Kawakami

Shunsuke Hosoumi

Takao Hamada

Tomoka Nakagawa

Satomi Mitsumori

Takeyoshi Watabe

Kaori Ogita

Hideko Yoshizumi

Yoshimi Ishiguro

Hiroshi Kadoma

Kyoko Takeda

Yui Yamada

Kanta Abe

Tomoka Hara

Miki Kurihara

Shunpei Yamazaki

Yuji Iwaki

Satomi Watabe

Satoko Shitagaki

Kunihiko Suzuki

Naoaki Hashimoto

Yohei Momma

Teruaki Ochiai

Mayumi Mikami

Yumiko Yoneda

Yuko Kawata

Kazuhei Narita

Yuko Kubota

Tomoya Hirose

Yui Yoshiyasu

Jyo Saito

A multicolor light-emitting element using fluorescence and phosphorescence, which has a small number of manufacturing steps owing to a relatively small number of layers to be formed and is advantageous for practical application can be provided. In addition, a multicolor light-emitting element using fluorescence and phosphorescence, which has favorable emission efficiency is provided. A light-emitting element which includes a light-emitting layer having a stacked-layer structure of a first light-emitting layer exhibiting light emission from a first exciplex and a second light-emitting layer exhibiting phosphorescence is provided.

Light-emitting element, light-emitting device, display device, electronic appliance, and lighting device

A secondary battery with excellent cycle performance is provided. The secondary battery is an all-solid-state battery including a positive electrode current collector layer, a base film, a positive electrode active material layer, a buffer layer, and a solid electrolyte layer. The base film contains titanium nitride. The positive electrode active material layer contains lithium cobalt oxide. The buffer layer contains titanium oxide. The solid electrolyte layer contains a titanium compound. By using titanium oxide for the buffer layer, a side reaction between the positive electrode active material layer and the solid electrolyte layer can be suppressed, and cycle performance can be improved.

Secondary battery and manufacturing method thereof

A positive electrode active material that has high capacity and excellent charge and discharge cycle performance for a secondary battery is provided. A positive electrode active material that inhibits a decrease in capacity in charge and discharge cycles is provided. A high-capacity secondary battery is provided. A secondary battery with excellent charge and discharge characteristics is provided. A highly safe or reliable secondary battery is provided. A positive electrode active material contains lithium, cobalt, oxygen, and aluminum and has a crystal structure belonging to a space group R-3m when Rietveld analysis is performed on a pattern obtained by powder X-ray diffraction. In analysis by X-ray photoelectron spectroscopy, the number of aluminum atoms is less than or equal to 0.2 times the number of cobalt atoms.

Lithium cobalt aluminum oxide positive electrode active material including aluminum-containing coating film and secondary battery

Provided is a positive electrode for a secondary battery, which has a small change in a crystal structure due to charging and discharging and has excellent cycle performance. The positive electrode for a secondary battery includes n positive electrode active material layers (n is an integer greater than or equal to 2), n−1 separation layer(s), and a positive electrode current collector layer. The positive electrode active material layers and the separation layer(s) are alternately stacked. The positive electrode active material layer contains lithium, cobalt, and oxygen. The separation layer contains a titanium compound. Titanium oxide and titanium nitride are preferable as the titanium compound, and titanium oxide is particularly preferable.

Positive electrode for secondary battery, secondary battery, and electronic device

To provide a light-emitting element which uses a fluorescent material as a light-emitting substance and has higher luminous efficiency. To provide a light-emitting element which includes a mixture of a thermally activated delayed fluorescent substance and a fluorescent material. By making the emission spectrum of the thermally activated delayed fluorescent substance overlap with an absorption band on the longest wavelength side in absorption by the fluorescent material in an Slevel of the fluorescent material, energy at an Slevel of the thermally activated delayed fluorescent substance can be transferred to the Sof the fluorescent material. Alternatively, it is also possible that the Sof the thermally activated delayed fluorescent substance is generated from part of the energy of a Tlevel of the thermally activated delayed fluorescent substance, and is transferred to the Sof the fluorescent material.

Light-emitting element

A novel organometallic complex with high reliability is provided. A light-emitting element includes an EL layer between a pair of electrodes. The EL layer includes at least a light-emitting layer. The light-emitting layer contains an organometallic complex. The organometallic complex includes a first ligand and a second ligand which are coordinated to a central metal. The HOMO is distributed over the first ligand, and the LUMO is distributed over the second ligand. The first ligand and the second ligand are cyclometalated ligands.

Light-emitting element, light-emitting device, electronic device, and lighting device

A light-emitting element with high emission efficiency. The light-emitting element includes a first organic compound, a second organic compound, and a guest material. The LUMO level of the first organic compound is lower than the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than the HOMO level of the second organic compound. The HOMO level of the guest material is higher than the HOMO level of the second organic compound. The energy difference between the LUMO level of the guest material and the HOMO level of the guest material is larger than the energy difference between the LUMO level of the first organic compound and the HOMO level of the second organic compound. The guest material has a function of converting triplet excitation energy into light emission. The first organic compound and the second organic compound form an exciplex.

Light-emitting element, display device, electronic device, and lighting device

To provide a light-emitting element with an improved reliability, a light-emitting element with a high current efficiency (or a high quantum efficiency), and a novel dibenzo[f,h]quinoxaline derivative that is favorably used in a light-emitting element which is one embodiment of the present invention. A light-emitting element includes an EL layer between an anode and a cathode. The EL layer includes a light-emitting layer; the light-emitting layer contains a first organic compound having an electron-transport property and a hole-transport property, a second organic compound having a hole-transport property, and a light-emitting substance; the combination of the first organic compound and the second organic compound forms an exciplex; the HOMO level of the first organic compound is lower than the HOMO level of the second organic compound; and a difference between the HOMO level of the first organic compound and the HOMO level of the second organic compound is less than or equal to 0.4 eV.

Light-emitting element, light-emitting device, electronic device, lighting device, and organic compound

A novel compound and a light-emitting element with high emission efficiency and a long lifetime are provided. The novel compound includes a benzofuropyrazine skeleton or a benzothienopyrazine skeleton, and each of a benzene ring and a pyrazine ring in the benzofuropyrazine skeleton or the benzothienopyrazine skeleton independently includes a substituent with a total number of carbon atoms of 6 to 100 inclusive. The light-emitting element includes the compound.

Light-emitting element, organic compound, light-emitting device, electronic device, and lighting device

A light-emitting element having high emission efficiency is provided. A light-emitting element having a low driving voltage is provided. A novel compound which can be used for a transport layer or as a host material or a light-emitting material of a light-emitting element is provided. A novel compound with a benzofuropyrimidine skeleton is provided. Also provided is a light-emitting element which includes the compound with the benzofuropyrimidine skeleton between a pair of electrodes.

Light-emitting element, compound, organic compound, display module, lighting module, light-emitting device, display device, lighting device, and electronic device

A novel mixed material for a light-emitting device with improved heat resistance is provided. The mixed material for a light-emitting device includes a first heteroaromatic compound and a second heteroaromatic compound. The first heteroaromatic compound includes a first heteroaromatic ring. The first heteroaromatic ring includes a ring including two or more nitrogen atoms and any one of a benzene ring and a pyridine ring or a ring including a diazine ring or a triazine ring. The second heteroaromatic compound includes a second heteroaromatic ring. The second heteroaromatic ring includes a ring including two or more nitrogen atoms and any one of a benzene ring and a pyridine ring or a ring including a diazine ring or a triazine ring. A structure of the first heteroaromatic ring is different from a structure of the second heteroaromatic ring.

Mixed material for light-emitting device

A light-emitting element containing a fluorescent material and having high emission efficiency is provided. The light-emitting element contains the fluorescent material and a host material. The host material contains a first organic compound and a second organic compound. The first organic compound and the second organic compound can form an exciplex. The minimum value of a distance between centroids of the fluorescent material and at least one of the first organic compound and the second organic compound is 0.7 nm or more and 5 nm or less.

A light-emitting element containing a fluorescent material and having high emission efficiency is provided. The light-emitting element contains the fluorescent material and a host material. The host material contains a first organic compound and a second organic compound. The first organic compound and the second organic compound can form an exciplex. The proportion of a delayed fluorescence component in light emitted from the exciplex is higher than or equal to 5%, and the delayed fluorescence component contains a delayed fluorescence component whose fluorescence lifetime is 10 ns or longer and 50 μs or shorter.

Growing community of inventors

Kanagawa, Japan

Tatsuyoshi Takahashi