Described are luminescent components with excellent performance and stability. The luminescent components comprise a first element 1 including first luminescent crystals 11 from the class of perovskite crystals, embedded a first polymer P1 and a second element 2 comprising a second solid polymer composition, said second polymer composition optionally comprising second luminescent crystals 12 embedded in a second polymer P2. Polymers P1 and P2 differ and are further specified in the claims. Also described are methods for manufacturing such components and devices comprising such components.

Described are luminescent components with excellent performance and stability. The luminescent components comprise a first element 1 including first luminescent crystals 11 from the class of perovskite crystals, embedded a first polymer P1 and a second element 2 comprising a second solid polymer composition, said second polymer composition optionally comprising second luminescent crystals 12 embedded in a second polymer P2. Polymers P1 and P2 differ and are further specified in the claims. Also described are methods for manufacturing such components and devices comprising such components.

A method of preparing a light-emitting material, the method including mixing a first precursor solution including a first precursor and a first solvent with a second precursor solution including a second precursor and a second solvent to form a precipitate, and separating the precipitate to obtain a light-emitting material, wherein a solubility of the first precursor in the first solvent may be greater than a solubility of the first precursor in the second solvent, and a solubility of the second precursor in the second solvent may be greater than a solubility of the second precursor in the first solvent. A light-emitting material prepared by the method, and a light-emitting device including the light-emitting material is also described.

The invention relates to a gas phase treatment method for modifying the surface of perovskite materials, which belongs to the field of preparation technology of perovskite material. The details are as follows: the perovskite material is exposed to a hydrogen halide vapor environment at atmospheric pressure. Hydrogen halide can effectively fill the defect sites on the perovskite surface and form stable strong chemical bonds with the perovskite surface. The modified perovskite solar cells based on the invention have enhanced resistance to high temperature, high humidity and strong light. The simulation test shows that the modified photoelectric device can work stably outdoors for nearly 10 years. The invention addresses the issue of poor stability commonly associated with halide perovskite materials, and it offers a low-cost process, which is expected to promote the industrialization and commercialization of perovskite solar cells.

The present invention provides a method for producing a solution of nanosheets, comprising the step of contacting an intercalated layered material with a polar aprotic solvent to produce a solution of nanosheets, wherein the intercalated layered material is prepared from a layered material selected from the group consisting of a transition metal dichalcogenide, a transition metal monochalcogenide, a transition metal trichalcogenide, a transition metal oxide, a metal halide, an oxychalcogenide, an oxypnictide, an oxyhalide of a transition metal, a trioxide, a perovskite, a niobate, a ruthenate, a layered III-VI semiconductor, black phosphorous and a V-VI layered compound. The invention also provides a solution of nanosheets and a plated material formed from nanosheets.

Phonon engineered, lanthanide doped upconverting nanoparticles with very low phonon energies and tunable methods of synthesis that adjust OA:OM ratio and reaction temperature are provided. Low phonon energy KPb.sub.2X.sub.5 (X=Cl, Br) upconverting nanoparticles, both doped and undoped, exhibit dramatically suppressed multiphonon relaxation, enhancing upconversion emission from higher lanthanide excited states and enabling room temperature observation of avalanche like upconversion by Nd.sup.3+ ions. Intrinsic optical bistability (IOB) of the materials can provide bit level functionality to all optical computing. The IOB of Nd.sup.3+ doped nanocrystals, which are either bright or dark at the same excitation power based on power history, illustrate the functionality. High contrast switching and IOB are enabled via the photon avalanche process, which sustains population inversion between the ground and the first excited 4f.sup.N states of Nd.sup.3+ ions. The IOB of these nanocrystals can be controlled by temporal pump modulation and can store information.

Disclosed is a perovskite light-emitting device with reduced defects in a perovskite thin film. The passivation layer in the perovskite light-emitting device is formed on the upper part of the perovskite thin film to eliminate defects in the perovskite nanocrystalline particles and resolve charge imbalance in the device, thereby improving maximum efficiency and maximum luminance of the light-emitting device.

Inorganic perovskites doped with oxygen atoms or fluorine atoms, methods for making the doped perovskites, and hard radiation detectors incorporating the doped perovskites as photoactive layers are provided. The doped perovskites utilize lead oxide, lead fluoride, or compounds that thermally decompose into lead oxide or lead fluoride as dopant atom sources. During the crystallization of a perovskite in the presence of the dopant atom sources, oxygen or fluoride atoms from the dopant source are incorporated into the perovskite crystal lattice.

A method of preparing a composition including crystalline particles of a halide perovskite, a composition and a perovskite-based device including the same. The halide perovskite has a chemical formula ABX.sub.3, wherein A is a monocation, B is selected from a combination of lead (II) and a dopant and X is selected from a halide.

A compound has a perovskite type crystal structure containing A which is a monovalent cation, B which is a metal ion, and X which is a halide ion as components. The perovskite type crystal structure has a unit cell volume of 0.2000 nm.sup.3 or more and 0.2150 nm.sup.3 or less, an ionic radius of B of 0.7 or more and 1.4 or less, and an ionic radius of X of 0.5 or more and 2.5 or less.