Methods of making luminescent perovskite-polymer composites are provided and structures using the same. Perovskite-polymer composites made by the method described herein are provided. The perovskite-polymer composite is useful in many applications including downconverters for backlight units (BLU) of liquid crystal displays (LCDs), as well as for and could be used for light emitting devices, lasers or as active absorber or passive luminescent concentrators for solar photovoltaic applications.

A quantum dot composition of an embodiment includes: a quantum dot; a ligand combined with a surface of the quantum dot; and a ligand scavenger having a nucleophilic reaction group.

A display device includes a light-emitting layer and a hole transport layer. The light-emitting layer includes quantum dots coordinated with a ligand including a thiol group. The hole transport layer includes VNPB that is chemically bonded to the thiol group.

A method for preparing three-dimensional perovskite nanopixels of a digital display is provided. The method includes steps of preparing precursor ink by mixing methylammonium halide and lead halide and adding them into another mixture, adding the precursor ink into a nanopipette, placing the nanopipette with the precursor ink above a silicon substrate and apart from the silicon substrate by a certain distance, configuring the nanopipette to come into contact with the Si substrate such that a portion of the precursor ink having an interface surface of a shape of a meniscus is formed between the nanopipette and the silicon substrate, performing rapid evaporation of the portion of the precursor ink to facilitate crystallization of perovskite, moving the nanopipette upwardly at a constant speed such that the crystallization of perovskite proceeds upwardly, and terminating the crystallization of perovskite to generate a freestanding nanopixel for emitting light.

An electrical component including a polymeric body which (i) defines at least one electrical connection; or (ii) is configured for attachment to an electrical cable or wire; or (iii) is configured for attachment to an electrical apparatus, wherein the polymeric body or a portion thereof includes a thermochromic composition which has a first colour condition below a first threshold temperature and a second colour condition if the composition is heated above the first threshold temperature, and wherein the thermochromic composition maintains the second colour condition until it is cooled below a second threshold temperature.

A synchronized piezoelectric and luminescence (SPL) material includes a core layer including light-emitting particles and a shell layer which is attached onto a surface of the core layer and includes ligands having a piezoelectric property. Therefore, a piezoelectric property and a luminescent property can be simultaneously implemented using a single SPL material in which piezoelectric ligands and light-emitting particles are chemically coupled.

Organic electroluminescent devices with lowered driving voltages, and enhanced efficiencies and lifetimes are provided.

Fluorescent material composite particles include translucent inorganic particles having a volume average particle diameter in a range of 30 nm or more and 500 nm or less, fluorescent nanoparticles having an average particle diameter in a range of 5 nm or more and 25 nm or less, and a first resin. At least a part of each of the translucent inorganic particles are embedded in the first resin. The translucent inorganic particles are unevenly distributed to a surface of the fluorescent material composite particles. The fluorescent material composite particles have a volume average particle diameter in a range of 0.5 μm or more and 50 μm or less.

A wavelength conversion member including a wavelength conversion layer containing a fluoride phosphor, quantum dots, a surfactant, and a resin. The fluoride phosphor contains fluoride particles having a specific composition and having particle size values within specific ranges. The quantum dots include at least one selected from a first crystalline nanoparticle and a second crystalline nanoparticle. The first crystalline nanoparticle has a specific composition. When irradiated with light having a wavelength of 450 nm, the first crystalline nanoparticle emits light having an emission peak at a wavelength in a range from 510 nm to 535 nm, and a full width at half maximum of the emission peak of the first crystalline nanoparticle is in a range from 10 nm to 30 nm. The second crystalline nanoparticle includes a chalcopyrite-type crystalline structure, and a full width at half maximum of the emission peak of the second crystalline nanoparticle is 45 nm or less.

Stable perovskite films having substantially-no phase transition within a predetermined temperature range are disclosed. In the films, formation of carrier traps is suppressed. Thermally stable perovskite solar cells and light-emitting devices using the films are also disclosed.