A light-emitting electrochemical cell 10 includes an emitting layer 12 and electrodes 13 and 14, one on each side of the emitting layer 12. The emitting layer 12 contains a light-emitting material and an ionic compound. The ionic compound has general formula (1), wherein M is N or P; R.sub.1, R.sub.2, R.sub.3, and R.sub.4 each independently represent a C1-C20 saturated aliphatic group; and X is preferably an anion having a phosphoric ester bond or a sulfuric ester bond. The light-emitting material is preferably an organic light-emitting polymer, a metal complex, an organic low molecular compound, or a quantum dot.

##STR00001##

This invention relates to a method for fabrication of electrode material in electronic devices by in situ-electrodeposition of metal or metalloid ions that are present in the device. In another aspect, the present invention relates to electronic devices and charge storage devices comprising the electrodes manufactured by said method. Furthermore, the present invention further relates to a method of enhancing charge injection in an electronic device or charge storage device comprising the steps of: pre-assembling an electronic device or charge storage device and subsequently applying an electric field to effect electrodeposition of an electrode layer in situ by reducing the metal or metalloid ions to a non-ionic state.

Provided are a method for manufacturing a perovskite nanocrystal particle light-emitter where an organic ligand is substituted, a light-emitter manufactured thereby, and a light emitting device using the same. A method for manufacturing an organic-inorganic-hybrid perovskite nanocrystal particle light-emitter where an organic ligand is substituted may comprise the steps of: preparing a solution including an organic-inorganic-hybrid perovskite nanocrystal particle light-emitter, wherein the organic-inorganic-hybrid perovskite nanocrystal particle light-emitter comprises an organic-inorganic-hybrid perovskite nanocrystal structure and a plurality of first organic ligands surrounding the organic-inorganic-hybrid perovskite nanocrystal structure; and adding, to the solution, a second organic ligand which is shorter than the first organic ligands or includes a phenyl group or a fluorine group, thereby substitutes the first organic ligands with the second organic ligand. Thus, since energy transfer or charge injection into the nanocrystal structure increases through ligand substitution, it is possible to further increase light emitting efficiency and increase durability and stability by means of a hydrophobic ligand.

The present disclosure relates to a composition that includes a first layer that includes a perovskite defined by ABX.sub.3 and a second layer that includes a perovskite-like material defined by at least one of A′.sub.2B′X′.sub.4, A′.sub.3B′.sub.2X′.sub.9, A′B′X′.sub.4, A′.sub.2B′X′.sub.6, and/or A′.sub.2AB′.sub.2X′.sub.7, where the first layer is adjacent to the second layer, A is a first cation, B is a second cation, X is a first anion, A′ is a third cation, B′ is a fourth cation, X′ is a second anion, and A′ is different than A.

Novel structures and compositions for multilayer light-emitting electrochemical cell devices are described, particularly those that are adapted to work with stable and printable electrode metals, that optimize recombination efficiency, lifetime and turn-on kinetics. In particular, embodiments of the present invention provide improved performance and extended lifetime for doped electronic devices, where ionic doping levels, ionic support materials content, and electronic transport content are advantageously structured within the device. The doping profile of mobile or semi-mobile ionic dopants is intentionally made to be non-uniform to enhance doping in the interface regions of a device where the active layer interfaces with the electrode.

The present disclosure is related to a method of manufacturing a light-emitting layer. The method of manufacturing a light-emitting layer may include forming a layer of metal first halide perovskite on a substrate, forming a first pattern comprising metal second halide perovskite in the layer of metal first halide perovskite, and forming a second pattern comprising metal third halide perovskite in the layer of metal first halide perovskite.

This disclosure provides a perovskite light-emitting diode with an adjustable light field, including a glass layer, an anode, a hole transport layer, an emission layer, an electron transport layer and a cathode in sequence from top to bottom. The electron transport layer is provided with a periodic nano-grating structure.

A class of crystals comprises an inorganic lattice in which organic molecules are embedded, thereby allowing macroscopic electro-optic responsiveness. The lattice is based on a metal halide perovskite structure. The organic molecules can be with an intrinsic dipole such that when aligned and fixed in place in the inorganic lattice, they induce electro-optic responsiveness in the macroscopic crystal. Alternatively, their mere presence in the structure can induce sufficient polarity in the scaffold itself for a similar responsiveness. The molecules themselves can comprise a carbon backbone that is completely conductive, partially conductive, or non-conductive, as well as zero, one or two functional groups that allow binding to the lattice and increased polarity.

Provided are a core-shell structured perovskite particle light-emitter, a method of preparing the same, and a light emitting device using the same. The core-shell structured perovskite particle light-emitter or metal halide perovskite particle light-emitter has a perovskite nanocrystal structure and a core-shell structured particle structure. Therefore, in the perovskite particle light-emitter of the present invention, as a shell is formed of a substance having a wider band gap than that of a core, excitons may be more dominantly confined in the core, and durability of the nanocrystal may be improved to prevent exposure of the core perovskite to the air using a perovskite or inorganic semiconductor, which is stable in the air, or a polymer.

A solid-liquid-solid phase transformation (SLSPT) approach is used for fabrication of perovskite periodic nanostructures. The pattern on a mold is replicated by perovskite through phase change of perovskite from initially solid state, then to liquid state, and finally to solid state. The LED comprising perovskite periodic nanostructure shows better performance than that with flat perovskite. Further, the perovskite periodic nanostructure from SLSPT can be applied in many optoelectronic devices, such as solar cells, light emitting diodes (LED), laser diodes, transistors, and photodetectors.