A method for preparing inorganic halogenated lead perovskite quantum dots and a display device are provided. The method includes: a first coordination solution preparing step, a cesium oleate solution preparing step, a centrifugal separation step, a second coordination solution preparing step, a first ion exchange step, and a second ion exchange step. The present invention also provides a display device including a quantum dot layer, wherein luminescent quantum dots of the quantum dot layer are inorganic halogenated lead cesium perovskite quantum dots of the present invention.

A coated phosphor comprises phosphor particles, wherein said phosphor particles comprise manganese-activated complex fluoride phosphors; and a coating on individual ones of said phosphor particles, said coating comprising a layer of carboxylic acid material encapsulating the individual phosphor particles.

A preservation method of a quantum dot and a quantum dot composition are provided. The method includes the following steps. A quantum dot is mixed with a preservative to form a quantum dot composition, wherein the preservative is a long-chain unsaturated compound, and based on the total weight of the quantum dot composition, the content of the quantum dot is 5 wt % to 80 wt %, and the content of the preservative is 20 wt % to 95 wt %. The quantum dot composition is sealed for preservation.

A luminescent substance particle including BaSnO.sub.3 having a perovskite-type structure, wherein the luminescent substance particle contains one of 0.07% by mass or less of Fe (iron), 0.005% by mass or less of Cr (chromium) and 0.02% by mass or less of Ni (nickel). A wavelength conversion film including the luminescent substance particle for converting a light in an ultraviolet region to a light in an infrared region. A wavelength conversion device including a substrate and the wavelength conversion film formed on the substrate.

A luminescent substance particle including BaSnO.sub.3 having a perovskite-type structure, wherein the luminescent substance particle contains one of 0.07% by mass or less of Fe (iron), 0.005% by mass or less of Cr (chromium) and 0.02% by mass or less of Ni (nickel). A wavelength conversion film including the luminescent substance particle for converting a light in an ultraviolet region to a light in an infrared region. A wavelength conversion device including a substrate and the wavelength conversion film formed on the substrate.

The present invention relates to a method for obtaining an n-type doped metal chalcogenide quantum dot solid-state element with optical gain for low-threshold, band-edge amplified spontaneous emission (ASE), comprising: —forming a metal chalcogenide quantum dot solid-state element, and —carrying out an n-doping process on its metal chalcogenide quantum dots to at least partially bleach its band-edge absorption, which comprises: —a partial substitution of chalcogen atoms by halogen atoms, in the metal chalcogenide quantum dots, and/or —a partial aliovalent-cation substitution of bivalent metal cations by trivalent cations, in the metal chalcogenide quantum dots; and —providing a substance on the metal chalcogenide quantum dots, to avoid oxygen p-doping. The present invention also relates to the obtained n-type doped metal chalcogenide quantum dot solid-state element, a method for obtaining a light emitter with that n-type doped metal chalcogenide quantum dot solid-state element, and the obtained light emitter.

Provided are a perovskite film and method for manufacturing the same, a perovskite electroluminescent device and method for manufacturing the same, and a display device, which belongs to the technical field of displaying. The perovskite film comprises a crystalline perovskite and a halogenated amine ligand grafted onto the crystalline perovskite. Since the perovskite film comprises the halogenated amine ligand, the surface of the perovskite film is smooth, and the surface coverage of the crystalline perovskite is high without significant void defects. Meanwhile, the perovskite film also has a high fluorescence quantum yield due to the halogenated amine ligand comprised in the perovskite film.

A quantum dot luminescent material and a method of producing thereof. The quantum dot luminescent material includes a hole injection layer, a hole transport layer, a quantum dot light emitting layer, an electron transport layer, and an electron injection layer. The quantum dot luminescent layer is located on the hole transport layer, and the quantum dot luminescent layer includes uniformly distributed perovskite nanodots.

A light emitting device includes a Chip Scale Packaged (CSP) LED, the CSP LED including an LED chip that generates blue excitation light; and a photoluminescence layer that covers a light emitting face of the LED chip, wherein the photoluminescence layer comprises from 75 wt % to 100 wt % of a manganese-activated fluoride photoluminescence material of the total photoluminescence material content of the layer. The device/CSP LED can further include a further photoluminescence layer that covers the first photoluminescence and that includes a photoluminescence material that generates light with a peak emission wavelength from 500 nm to 650 nm.

A composite interface transport material-based perovskite photovoltaic, light emission and light detection multi-functional device and a preparation method therefor. The multi-functional device comprises a transparent conductive glass, a composite electron transport layer, a perovskite active layer, a composite hole transport layer and a metal electrode layer which are sequentially arranged in a stacked manner from bottom to top. The work functions of the interface transport layers are adjusted by means of the multi-element interface transport materials, so that the work functions of the electron transport layer and the hole transport layer are respectively levelled with conduction band and valence band positions of the perovskite active layer. According to experiment result comparisons, the photoelectric conversion efficiency and the luminous efficiency of the perovskite multi-functional device, after energy band regulation, are significantly increased.