Disclosed are a metal halide perovskite light-emitting material with controlled defects and wavelength converting body having the same, and light-emitting device. Monvalent organic cation (A.sub.2) contained in the perovskite nanocrystal can stabilize the perovskite nanocrystal and suppress the generation of defects in the crystal due to the entropy effect. Remnant A.sub.2 cations not included in the perovskite nanocrystal form a structure surrounding the perovskite nanocrystal particles, and passivate defects generated on the surface of the perovskite nanocrystal particles. Photoluminescence quantum efficiency, photoluminescence lifetime, and stability are improved through passivation of defects, and the metal halide perovskite light-emitting material can be effectively used in a light-emitting layer or a wavelength conversion layer of a light-emitting device.

Disclosed are a metal halide perovskite light-emitting material with controlled defects and wavelength converting body having the same, and light-emitting device. Monvalent organic cation (A.sub.2) contained in the perovskite nanocrystal can stabilize the perovskite nanocrystal and suppress the generation of defects in the crystal due to the entropy effect. Remnant A.sub.2 cations not included in the perovskite nanocrystal form a structure surrounding the perovskite nanocrystal particles, and passivate defects generated on the surface of the perovskite nanocrystal particles. Photoluminescence quantum efficiency, photoluminescence lifetime, and stability are improved through passivation of defects, and the metal halide perovskite light-emitting material can be effectively used in a light-emitting layer or a wavelength conversion layer of a light-emitting device.

A light-emitting layer for a halide perovskite light-emitting device, a method for manufacturing the same and a perovskite light-emitting device using the same are disclosed. The light-emitting layer can be manufactured by forming a first nanoparticle thin film by coating, on a member, a solution comprising halide perovskite nanoparticles having a halide perovskite nanocrystalline structure. Thereby, a nanoparticle light emitter has therein a halide perovskite having a crystal structure in which FCC and BCC are combined; and can show high color purity. In addition, it is possible to improve the luminescence efficiency and luminance of a device by making perovskite as nanoparticles and then introducing the same into a light-emitting layer.

A light-emitting layer for a halide perovskite light-emitting device, a method for manufacturing the same and a perovskite light-emitting device using the same are disclosed. The light-emitting layer can be manufactured by forming a first nanoparticle thin film by coating, on a member, a solution comprising halide perovskite nanoparticles having a halide perovskite nanocrystalline structure. Thereby, a nanoparticle light emitter has therein a halide perovskite having a crystal structure in which FCC and BCC are combined; and can show high color purity. In addition, it is possible to improve the luminescence efficiency and luminance of a device by making perovskite as nanoparticles and then introducing the same into a light-emitting layer.

A light emitting device is provided. The device comprises a first electrode, a second electrode and at least two emissive layers. A first emissive layer of the at least two emissive layers is disposed over the first electrode. A second emissive layer of the at least two emissive layers is disposed over the first emissive layer. The first emissive layer is in contact with the second emissive layer. The second electrode is disposed over the second emissive layer. At least one emissive layer of the at least two emissive layers comprises a perovskite light emitting material. The device comprises at least one further emissive layer of the at least two emissive layers, wherein the at least one further emissive layer comprises a perovskite light emitting material, an organic light emitting material or a quantum dot light emitting material.

A light emitting device is provided. The device comprises a first electrode, a second electrode and at least two emissive layers. A first emissive layer of the at least two emissive layers is disposed over the first electrode. A second emissive layer of the at least two emissive layers is disposed over the first emissive layer. The first emissive layer is in contact with the second emissive layer. The second electrode is disposed over the second emissive layer. At least one emissive layer of the at least two emissive layers comprises a perovskite light emitting material. The device comprises at least one further emissive layer of the at least two emissive layers, wherein the at least one further emissive layer comprises a perovskite light emitting material, an organic light emitting material or a quantum dot light emitting material.

An object of the present disclosure is to provide an all solid fluoride ion battery that has a favorable capacity property. The present disclosure achieves the object by providing an all solid fluoride ion battery comprising: a cathode layer, an anode layer, and a solid electrolyte layer formed between the cathode layer and the anode layer; wherein the anode layer includes a metal fluoride containing an M1 element, an M2 element, and a F element; the M1 element is a metal element that fluorination and defluorination occur at a potential, versus Pb/PbF.sub.2, of −2.5 V or more; the M2 element is a metal element that neither fluorination nor defluorination occur at a potential, versus Pb/PbF.sub.2, of −2.5 V or more; and the M2 element is a metal element that, when in a form of a fluoride, fluoride ion conductivity is 1×10.sup.−4 S/cm or more at 200° C.

An object of the present disclosure is to provide an all solid fluoride ion battery that has a favorable capacity property. The present disclosure achieves the object by providing an all solid fluoride ion battery comprising: a cathode layer, an anode layer, and a solid electrolyte layer formed between the cathode layer and the anode layer; wherein the anode layer includes a metal fluoride containing an M1 element, an M2 element, and a F element; the M1 element is a metal element that fluorination and defluorination occur at a potential, versus Pb/PbF.sub.2, of −2.5 V or more; the M2 element is a metal element that neither fluorination nor defluorination occur at a potential, versus Pb/PbF.sub.2, of −2.5 V or more; and the M2 element is a metal element that, when in a form of a fluoride, fluoride ion conductivity is 1×10.sup.−4 S/cm or more at 200° C.

The invention relates to a process for producing a crystalline A/M/X material, which crystalline A/M/X material comprises a compound of formula [A].sub.a[M].sub.b[X].sub.c wherein: [A] comprises one or more A cations; [M] comprises one or more M cations which are metal or metalloid cations; [X] comprises one or more X anions; a is a number from 1 to 6; b is a number from 1 to 6; and c is a number from 1 to 18. The process is capable of producing crystalline A/M/X materials while precisely controlling their stoichiometry, leading to products with finely tunable optical properties such as peak emission wavelength. The invention also relates to process for producing a thin film comprising the crystalline A/M/X material of the invention, and to a thin film obtainable by the process of the invention. An optoelectronic device comprising the thin film is also provided.

The invention relates to a process for producing a crystalline A/M/X material, which crystalline A/M/X material comprises a compound of formula [A].sub.a[M].sub.b[X].sub.c wherein: [A] comprises one or more A cations; [M] comprises one or more M cations which are metal or metalloid cations; [X] comprises one or more X anions; a is a number from 1 to 6; b is a number from 1 to 6; and c is a number from 1 to 18. The process is capable of producing crystalline A/M/X materials while precisely controlling their stoichiometry, leading to products with finely tunable optical properties such as peak emission wavelength. The invention also relates to process for producing a thin film comprising the crystalline A/M/X material of the invention, and to a thin film obtainable by the process of the invention. An optoelectronic device comprising the thin film is also provided.