Disclosed are an organic proton-type ionic liquid, a film with a two-dimensional perovskite pure-phase quantum well structure, a preparation method and use thereof. The chemical formula of the organic proton-type alkylamine acetate ionic liquid is RNH.sub.3.sup.+—RCOO.sup.−, where R represents an alkyl group of C4-8 or a phenyl group, preferably, the chemical formula of the organic proton-type alkylamine acetate ionic liquid is CH.sub.3(CH.sub.2).sub.3NH.sub.3.sup.+—CH.sub.2COO.sup.−. The organic proton-type alkylamino acetate ionic liquid disclosed in the present disclosure can be used to prepare perovskite material, the prepared perovskite film thereby can form a pure-phase single quantum well, and the crystal grain size of the film can reach the level of micrometers or even millimeters.

Provided are a metal oxide composition, a light-emitting device using the metal oxide composition, and an electronic apparatus including the light-emitting device. The metal oxide composition includes a solvent including a first solvent and a second solvent, and a metal oxide, wherein the first solvent and the second solvent are different from each other, an amount of the first solvent is greater than an amount of the second solvent, and a boiling point of the second solvent is greater than a boiling point of the first solvent.

Provided are a metal oxide composition, a light-emitting device using the metal oxide composition, and an electronic apparatus including the light-emitting device. The metal oxide composition includes a solvent including a first solvent and a second solvent, and a metal oxide, wherein the first solvent and the second solvent are different from each other, an amount of the first solvent is greater than an amount of the second solvent, and a boiling point of the second solvent is greater than a boiling point of the first solvent.

An object of the present invention is to provide an ink composition for manufacturing an organic semiconductor device, the ink composition allowing an organic semiconductor material with a rigid main chain into an ink having an optimal solute concentration for a single-crystal formation process. The present invention provides an ink composition for manufacturing an organic semiconductor device, the ink composition including at least one solvent selected from Naphthalene Compound (A) and at least one solute. The isomer content of Naphthalene Compound (A) is preferably 2% or less in terms of a percentage for peak area with Naphthalene Compound (A) being 100% in gas chromatography. Naphthalene Compound (A): a compound represented by Formula (a), where in Formula (a), R is as defined in the description.

A method of forming a halide perovskite nanocrystal array having a plurality of halide perovskite nanocrystals arranged in a pattern can include coating an array of pens with a first ink comprising at least one first perovskite precursor having the formula AX and at least one second perovskite precursor having the formula BX′.sub.2 dissolved in a solvent. A is a cation, B is a metal, and X and X′ are each a halogen. The method further includes contacting a substrate with the coated pen array to thereby deposit the first ink indias a pattern of printed indicia on the substrate. The printed indicia form nanoreactors on the substrate and a halide perovskite nanocrystal nucleates and grows within each nanoreactor to form the halide perovskite nanocrystal array.

A printing formulation, an electronic device comprising a function layer prepared from the printing formulation and a preparation method for obtaining a functional material thin film by utilizing the printing formulation. The printing formulation comprises at least one functional material and at least one inorganic ester solvent, and the inorganic ester solvent can be selected from alkyl borate or alkyl phosphate.

The present invention relates to a formulation containing at least one organic functional material and at least four different organic solvents, a first organic solvent A, a second organic solvent B, a third organic solvent C, and a fourth organic solvent D, wherein the first organic solvent A comprises a group, which is capable of receiving or giving a hydrogen bonding, the second organic solvent B has a boiling point in the range from 50 to 350° C., the third organic solvent C has a boiling point in the range from 100 to 300° C., and the fourth organic solvent D has a boiling point in the range from 200 to 400° C., is present in an amount from 0.01 to 1 vol.-% and has a viscosity of ≥15 mPas, the solubility of the at least one organic functional material in the second organic solvent B and in the fourth organic solvent D is ≥5 g/l, the boiling point of the third organic solvent C is at least 10° C. lower than the boiling point of the second organic solvent B; and the boiling point of the fourth organic solvent D is at least 10° C. higher than the boiling point of the second organic solvent B; as well as to electroluminescent devices prepared by using these formulations.

A light emitting device including a first electrode and a second electrode facing each other, an emission layer disposed between the first electrode and the second electrode, wherein the emission layer includes a plurality of quantum dots and metal carboxylate having at least one hydrocarbon group of at least one carbon atoms, and the plurality of quantum dots includes a first organic ligand, and does not include cadmium and lead, and a method of manufacturing the same.

According to an embodiment, a method of manufacturing an organic electronic device including a stack including a first electrode layer, one or more functional layers, and a second electrode layer, the one or more functional layers and the second electrode layer being formed in this order on the first electrode layer, comprises: a first layer forming step of forming a first layer 24 among the layers included in the stack; and a second layer forming step of forming a second layer on the first layer by using a coating solution containing a material for the second layer and a solvent with boiling point of 160° C. or more, the second layer being in contact with the first layer. In the first layer forming step, the first layer is formed with a thickness t smaller than a desired thickness such that the first layer has the desired thickness T due to an increase in a thickness of the first layer as the second layer is formed.

Photovoltaic devices, and methods of fabricating photovoltaic devices. The photovoltaic devices may include a first electrode, at least one quantum dot layer, at least one semiconductor layer, and a second electrode. The first electrode may include a layer including Cr and one or more silver contacts.